Inflammation, trauma, or nerve injury may cause enduring hyperalgesia, an enhanced sensitivity to painful stimuli. Neurons in lamina I of the spinal dorsal horn that express the neurokinin 1 receptor for substance P mediate this abnormal pain sensitivity by an unknown cellular mechanism. We report that in these, but not in other nociceptive lamina I cells, neurokinin 1 receptor-activated signal transduction pathways and activation of low-threshold (T-type) voltage-gated calcium channels synergistically facilitate activity- and calcium-dependent long-term potentiation at synapses from nociceptive nerve fibers. Thereby, memory traces of painful events are retained.

The endothelium plays a critical role in the control of vasomotor tone by the release of vasoactive substances. Because endothelial injury or dysfunction is considered important very early in atherogenesis, we hypothesized that abnormal endothelial function precedes the angiographic detection of coronary atherosclerosis in the human coronary circulation. The coronary vasomotor responses to three different endothelium-mediated stimuli (intracoronary infusion of acetylcholine 10(-8) to 10(-6) M, increase in blood flow to induce flow-dependent dilation, and sympathetic stimulation by cold pressor testing) were assessed by quantitative angiography and subselective intracoronary Doppler flow velocity measurements within the left anterior descending coronary artery in 38 patients. All three stimuli elicited epicardial artery dilation in all 11 patients with smooth coronary arteries and absence of risk factors for coronary artery disease (group 1). All nine patients with smooth coronary arteries but with hypercholesterolemia (group 2) demonstrated a selective impairment in endothelial function with vasoconstriction (35 +/- 12.7% decrease in mean luminal area) in response to acetylcholine but showed a preserved flow-dependent dilation (15.5 +/- 4.4% increase in mean luminal area) and vasodilation in response to cold pressor testing (14.2 +/- 4.6% increase in mean luminal area). In all nine patients with an angiographically defined smooth coronary artery segment but with evidence of atherosclerosis elsewhere in the coronary system (group 3), both acetylcholine and cold pressor testing induced vasoconstriction (26.2 +/- 8.7% and 18.7 +/- 7.9% decrease in mean luminal area, respectively), whereas flow-dependent dilation was preserved (20.4 +/- 8.7% increase in mean luminal area). In the nine patients with angiographic evidence of wall irregularities (group 4), flow-dependent dilation was also abolished and vasoconstriction occurred in response to acetylcholine and cold pressor testing (34.5 +/- 10.7% and 19.9 +/- 6.3% decrease in mean luminal area, respectively). All coronary artery segments dilated in response to nitroglycerin, suggesting preserved function of vascular smooth muscle. Despite similar reductions in coronary vascular resistance in response to the smooth muscle relaxant papaverin, patients with hypercholesterolemia demonstrated a selective impairment of vasodilation of the resistance vasculature in response to acetylcholine (p less than 0.05 versus groups 1, 3, and 4). Thus, there is a progressive impairment of endothelial vasoactive functioning in coronary arteries of patients with different early stages of atherosclerosis, beginning with a selective endothelial dysfunction in angiographically defined normal arteries in patients with hypercholesterolemia and progressively worsening to a complete loss of endothelium-mediated vasodilation in angiographically defined atherosclerotic coronary arteries.(ABSTRACT TRUNCATED AT 400 WORDS)

BACKGROUND

Overly aggressive diuresis leading to intravascular volume depletion has been proposed as a cause for worsening renal function during the treatment of decompensated heart failure. If diuresis occurs at a rate greater than extravascular fluid can refill the intravascular space, the concentration of such intravascular substances as hemoglobin and plasma proteins increases. We hypothesized that hemoconcentration would be associated with worsening renal function and possibly would provide insight into the relationship between aggressive decongestion and outcomes.

RESULTS

Subjects in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness trial limited data set with a baseline/discharge pair of hematocrit, albumin, or total protein values were included (336 patients). Baseline-to-discharge increases in these parameters were evaluated, and patients with>>or=2 in the top tertile were considered to have evidence of hemoconcentration. The group experiencing hemoconcentration received higher doses of loop diuretics, lost more weight/fluid, and had greater reductions in filling pressures (P<0.05 for all). Hemoconcentration was strongly associated with worsening renal function (odds ratio, 5.3; P<0.001), whereas changes in right atrial pressure (P=0.36) and pulmonary capillary wedge pressure (P=0.53) were not. Patients with hemoconcentration had significantly lower 180-day mortality (hazard ratio, 0.31; P=0.013). This relationship persisted after adjustment for baseline characteristics (hazard ratio, 0.16; P=0.001).

CONCLUSIONS

Hemoconcentration is significantly associated with measures of aggressive fluid removal and deterioration in renal function. Despite this relationship, hemoconcentration is associated with substantially improved survival. These observations raise the question of whether aggressive decongestion, even in the setting of worsening renal function, can positively affect survival.

BACKGROUND

Adults aged 18 to 24 years, many of whom are in college, represent the youngest legal targets for tobacco industry marketing. Cigarette smoking has been described among college students, but little is known about non-cigarette tobacco use by college students or cigar use by adults of any age.

OBJECTIVE

To assess the prevalence of all forms of tobacco use (cigarettes, cigars, pipes, and smokeless tobacco) among US college students and to identify student- and college-level factors associated with use of each product.

METHODS

The Harvard College Alcohol Survey, a self-administered survey conducted in 1999.

METHODS

One hundred nineteen nationally representative US 4-year colleges.

METHODS

A total of 14,138 randomly selected students (60% response rate).

METHODS

Self-report of current (in the past 30 days), past-year, and lifetime use of cigarettes, cigars, pipes, smokeless tobacco, and all tobacco products.

RESULTS

Nearly half (45.7%) of respondents had used a tobacco product in the past year and one third (32.9%) currently used tobacco. Cigarettes accounted for most of the tobacco use (28.5% current prevalence), but cigar use was also substantial (37.1% lifetime prevalence, 23.0% past-year prevalence, and 8.5% current prevalence) and combinations of the 2 were common. Total tobacco use was higher in men than in women (37. 9% vs 29.7%; P<.001), despite nearly identical current cigarette smoking rates between the sexes (28.5% for women vs 28.4% for men), because of greater use of cigars (current prevalence, 15.7% vs 3.9%; P<.001) and smokeless tobacco (current prevalence, 8.7% vs 0.4%; P<. 001) by men. Tobacco use was significantly higher among white students (P<.001), users of other substances (alcohol and marijuana) (P<.001), and students whose priorities were social rather than educational or athletic (P<.05). Among students who had used both cigars and cigarettes, only 8.9% smoked cigars at an earlier age than they had smoked cigarettes.

CONCLUSIONS

Our study indicates that tobacco use is common among college students and is not limited to cigarettes. College appears to be a time when many students are trying a range of tobacco products and are in danger of developing lifelong nicotine dependence. National efforts to monitor and reduce tobacco use of all types should expand to focus on college students and other young adults. JAMA. 2000;284:699-705

BACKGROUND

Research has implicated an addictive process in the development and maintenance of obesity. Although parallels in neural functioning between obesity and substance dependence have been found, to our knowledge, no studies have examined the neural correlates of addictive-like eating behavior.

OBJECTIVE

To test the hypothesis that elevated "food addiction" scores are associated with similar patterns of neural activation as substance dependence.

METHODS

Between-subjects functional magnetic resonance imaging study.

METHODS

A university neuroimaging center.

METHODS

Forty-eight healthy young women ranging from lean to obese recruited for a healthy weight maintenance trial.

METHODS

The relation between elevated food addiction scores and blood oxygen level-dependent functional magnetic resonance imaging activation in response to receipt and anticipated receipt of palatable food (chocolate milkshake).

RESULTS

Food addiction scores (N = 39) correlated with greater activation in the anterior cingulate cortex, medial orbitofrontal cortex, and amygdala in response to anticipated receipt of food (P < .05, false discovery rate corrected for multiple comparisons in small volumes). Participants with higher (n = 15) vs lower (n = 11) food addiction scores showed greater activation in the dorsolateral prefrontal cortex and the caudate in response to anticipated receipt of food but less activation in the lateral orbitofrontal cortex in response to receipt of food (false discovery rate-corrected P < .05).

CONCLUSIONS

Similar patterns of neural activation are implicated in addictive-like eating behavior and substance dependence: elevated activation in reward circuitry in response to food cues and reduced activation of inhibitory regions in response to food intake.

Incubation for a short time of arachidonic acid with the microsomal fraction of a homogenate of the vesicular gland of sheep in the presence of 1 mM p-mercuribenzoate followed by extraction and silicic acid chromatography yielded two prostaglandin endoperoxides. The structures of these compounds, i.e., 15-hydroperoxy-9alpha,11alpha-peroxidoprosta-5,13-dienoic acid (prostaglandin G(2)) and 15-hydroxy-9alpha,11alpha-peroxidoprosta-5,13-dienoic acid (prostaglandin H(2)), were assigned mainly by a number of chemical transformations into previously known prostaglandins. The new prostaglandins were 50-200 times (prostaglandin G(2)) and 100-450 times (prostaglandin H(2)) more active than prostaglandin E(2) on the superfused aorta strip. The half-life of the prostaglandin endoperoxides in aqueous medium (about 5 min) was significantly longer than that of "rabbit aorta-contracting substance" released from guinea pig lung, indicating that none of the prostaglandin endoperoxides is identical with this factor. Addition of 10-300 ng/ml of the endoperoxides to suspensions of washed human platelets resulted in rapid aggregation. Furthermore, platelet aggregation induced by thrombin was accompanied by release of material reducible by stannous chloride into prostaglandin F(2alpha), thus indicating the involvement of endogenous prostaglandin endoperoxides in platelet aggregation.

OBJECTIVE

The purpose of this study was to provide nationally representative data on the prevalence, sociodemographic correlates, and comorbidity of antisocial syndromes across alcohol and 8 specific drug use disorders, including sedative, tranquilizer, opiate, stimulant, hallucinogen, cannabis, cocaine, and inhalant/solvent abuse and dependence.

METHODS

This study is based on a nationally representative sample of adults. Lifetime prevalences of antisocial syndromes were estimated and logistic regression analyses were used to examine associations between antisocial syndromes and sociodemographic characteristics and substance use disorders. Diagnoses were made according to the criteria of the DSM-IV using the National Institute on Alcohol Abuse and Alcoholism Alcohol Use Disorder and Associated Disabilities Interview Schedule-DSM-IV Version.

RESULTS

The lifetime prevalences of antisocial personality disorder (APD), conduct disorder, and adult antisocial behavior were 3.6%, 1.1%, and 12.3%, respectively. Prevalences of alcohol use disorders and drug use disorders were 30.3% and 10.3%, respectively. In general, men and individuals who were younger, widowed/separated/divorced, of lower socioeconomic status, and living in urban areas or in the West were more likely to have antisocial syndromes. Native Americans were more likely and Asians and Hispanics were less likely to have APD and adult antisocial behavior. Virtually all of the associations between APD and adult antisocial behavior and specific substance use disorders were positive and statistically significant (p < .05). Significant associations between conduct disorder and substance use disorders were concentrated among women.

CONCLUSIONS

Comorbidity of specific substance disorders with antisocial syndromes is very common in the U.S. population. Further work in many directions is indicated by the results of this study, including the factors that give rise to the associations and the treatment and prevention implications of these conditions when comorbid.

Since the initial observations that stimulation of sensory neurons produces vasodilation, plasma extravasation, and hypersensitivity, much progress has been made in understanding the etiology of neurogenic inflammation. Studies have focused largely on the role of the neuropeptides, substance P and calcitonin gene-related peptide, which are released in the periphery by activation of small diameter sensory neurons. Recent work, however, has begun to emphasize the cellular mechanisms involved in regulating the release of proinflammatory substances from sensory neurons. In this perspective, discussion centers on a number of inflammatory mediators that activate various signal transduction pathways to augment excitability of and transmitter release from sensory neurons. Emphasis is placed on those pathways where multiple lines of evidence support their importance in initiating neurogenic inflammation. Recent studies, however, support the notion that there are novel compounds released during injury that can stimulate or sensitize sensory neurons. Furthermore, only now are intracellular signaling pathways that have been identified in other cell systems being studied in sensory neurons to establish their role in neurogenic inflammation. The challenge remains to ascertain the critical transduction pathways that regulate transmitter release from sensory neurons since this phenomenon triggers neurogenic inflammation. In addition, the cellular mechanisms involved in alterations in neuronal excitability during injury and the cellular pathways that maintain the inflammatory response over time need to be determined. With these advances, we will be able to develop therapeutic interventions to minimize deleterious consequences of neurogenic inflammation.

BACKGROUND

Depression and substance abuse are common and costly disorders that frequently co-occur, but controversy about effective treatment for patients with both disorders persists.

OBJECTIVE

To conduct a systematic review and meta-analysis to quantify the efficacy of antidepressant medications for treatment of combined depression and substance use disorders.

METHODS

PubMed, MEDLINE, and Cochrane database search (1970-2003), using the keywords antidepressant treatment or treatment depressed in conjunction with each of the following alcohol dependence, benzodiazepine dependence, opiate dependence, cocaine dependence, marijuana dependence, and methadone; a search of bibliographies; and consultation with experts in the field.

METHODS

Among inclusion criteria used for study selection were prospective, parallel group, double-blind, controlled clinical trials with random assignment to an antidepressant medication or placebo for which trial patients met standard diagnostic criteria for current alcohol or other drug use and a current unipolar depressive disorder. Of the more than 300 citations extracted, 44 were placebo-controlled clinical trials, 14 of which were selected for this analysis and included 848 patients: 5 studies of tricyclic antidepressants, 7 of selective serotonin re-uptake inhibitors, and 2 from other classes

METHODS

We independently screened the titles and abstracts of each citation, identified placebo-controlled trials of patients with both substance dependence and depression, applied the inclusion criteria, and reached consensus. Data on study methods, sample characteristics, and depression and substance use outcomes were extracted. The principal measure of effect size was the standardized difference between means on the Hamilton Depression Scale (HDS).

RESULTS

For the HDS score, the pooled effect size from the random-effects model was 0.38 (95% confidence interval, 0.18-0.58). Heterogeneity of effect on HDS across studies was significant (P <.02), and studies with low placebo response showed larger effects. Moderator analysis suggested that diagnostic methods and concurrent psychosocial interventions influenced outcome. Studies with larger depression effect sizes (>0.5) demonstrated favorable effects of medication on measures of quantity of substance use, but rates of sustained abstinence were low.

CONCLUSIONS

Antidepressant medication exerts a modest beneficial effect for patients with combined depressive- and substance-use disorders. It is not a stand-alone treatment, and concurrent therapy directly targeting the addiction is also indicated. More research is needed to understand variations in the strength of the effect, but the data suggest that care be exercised in the diagnosis of depression-either by observing depression to persist during at least a brief period of abstinence or through efforts by clinical history to screen out substance-related depressive symptoms.

OBJECTIVE

To examine the long-term effects of an intervention combining teacher training, parent education, and social competence training for children during the elementary grades on adolescent health-risk behaviors at age 18 years.

METHODS

Nonrandomized controlled trial with follow-up 6 years after intervention.

METHODS

Public elementary schools serving high-crime areas in Seattle, Wash.

METHODS

Of the fifth-grade students enrolled in participating schools, 643 (76%) were given written parental consent for the longitudinal study and 598 (93%) were followed up and interviewed at age 18 years.

METHODS

A full intervention provided in grades 1 through 6 of 5 days of in-service training for teachers each intervention year, developmentally appropriate parenting classes offered to parents when children were in grades 1 through 3 and 5 through 6, and developmentally adjusted social competence training for children in grades 1 and 6. A late intervention, provided in grades 5 and 6 only, paralleled the full intervention at these grades.

METHODS

Self-reported violent and nonviolent crime, substance use, sexual activity, pregnancy, bonding to school, school achievement, grade repetition and school dropout, suspension and/or expulsion, and school misbehavior; delinquency charges from court records; grade point average; California Achievement Test scores: and disciplinary action reports from school records.

RESULTS

Fewer students receiving full intervention than control students reported violent delinquent acts (48.3% vs 59.7%; P=.04), heavy drinking (15.4% vs 25.6%; P=.04), sexual intercourse (72.1% vs 83.0%; P=.02), having multiple sex partners (49.7% vs 61.5%; P=.04), and pregnancy or causing pregnancy (17.1% vs 26.4%; P=.06) by age 18 years. The full intervention student group reported more commitment (P=.03) and attachment (P=.006) to school, better academic achievement (P=.01), and less school misbehavior (P=.02) than control students. Late intervention in grades 5 and 6 only did not significantly affect health-risk behaviors in adolescence.

CONCLUSIONS

A package of interventions with teachers, parents, and children provided throughout the elementary grades can have enduring effects in reducing violent behavior, heavy drinking, and sexual intercourse by age 18 years among multiethnic urban children. Results are consistent with the theoretical model guiding the intervention and support efforts to reduce health-risk behaviors through universal interventions in selected communities or schools serving high-crime neighborhoods.

Inflammatory mediators play a key role in acute pancreatitis and the resultant multiple organ dysfunction syndrome, which is the primary cause of death in this condition. Recent studies have confirmed the critical role played by inflammatory mediators such as TNF-alpha, IL-1beta, IL-6, IL-8, PAF, IL-10, C5a, ICAM-1, and substance P. The systemic effects of acute pancreatitis have many similarities to those of other conditions such as septicaemia, severe burns, and trauma. The delay between the onset of inflammation in the pancreas and the development of the systemic response makes acute pancreatitis an ideal experimental and clinical model with which to study the role of inflammatory mediators and to test novel therapies. Elucidation of the key mediators involved in the pathogenesis of acute pancreatitis will facilitate the development of clinically effective anti-inflammatory therapy.

The blood-brain barrier (BBB) serves as a protective mechanism for the brain by preventing entry of potentially harmful substances from free access to the central nervous system (CNS). Tight junctions present between the brain microvessel endothelial cells form a diffusion barrier, which selectively excludes most blood-borne substances from entering the brain. Astrocytic end-feet tightly ensheath the vessel wall and appear to be critical for the induction and maintenance of the barrier properties of the brain capillary endothelial cells. Because of these properties, the BBB only allows entry of lipophilic compounds with low molecular weights by passive diffusion. However, many lipophilic drugs show negligible brain uptake. They are substrates for drug efflux transporters such as P-glycoprotein (Pgp), multidrug resistance proteins (MRPs) or organic anion transporting polypeptides (OATPs) that are expressed at brain capillary endothelial cells and/or astrocytic end-feet and are key elements of the molecular machinery that confers the special permeability properties to the BBB. The combined action of these carrier systems results in rapid efflux of xenobiotics from the CNS. The objective of this review is to summarize transporter characteristics (cellular localization, specificity, regulation, and potential inhibition) for drug efflux transport systems identified in the BBB and blood-cerebrospinal fluid (CSF) barrier. A variety of experimental approaches available to ascertain or predict the impact of efflux transport on brain access of therapeutic drugs also are described and critically discussed. The potential impact of efflux transport on the pharmacodynamics of agents acting in the CNS is illustrated. Furthermore, the current knowledge about drug efflux transporters as a major determinant of multidrug resistance of brain diseases such as epilepsy is reviewed. Finally, we summarize strategies for modulating or by-passing drug efflux transporters at the BBB as novel therapeutic approaches to drug-resistant brain diseases.

The aim of this investigation was to determine whether murine models of inflammatory, neuropathic and cancer pain are each characterized by a unique set of neurochemical changes in the spinal cord and sensory neurons. All models were generated in C3H/HeJ mice and hyperalgesia and allodynia behaviorally characterized. A variety of neurochemical markers that have been implicated in the generation and maintenance of chronic pain were then examined in spinal cord and primary afferent neurons.Three days after injection of complete Freund's adjuvant into the hindpaw (a model of persistent inflammatory pain) increases in substance P, calcitonin gene-related peptide, protein kinase C gamma, and substance P receptor were observed in the spinal cord. Following sciatic nerve transection or L5 spinal nerve ligation (a model of persistent neuropathic pain) significant decreases in substance P and calcitonin gene-related peptide and increases in galanin and neuropeptide Y were observed in both primary afferent neurons and the spinal cord. In contrast, in a model of cancer pain induced by injection of osteolytic sarcoma cells into the femur, there were no detectable changes in any of these markers in either primary afferent neurons or the spinal cord. However, in this cancer-pain model, changes including massive astrocyte hypertrophy without neuronal loss, increase in the neuronal expression of c-Fos, and increase in the number of dynorphin-immunoreactive neurons were observed in the spinal cord, ipsilateral to the limb with cancer. These results indicate that a unique set of neurochemical changes occur with inflammatory, neuropathic and cancer pain in C3H/HeJ mice and further suggest that cancer induces a unique persistent pain state. Determining whether these neurochemical changes are involved in the generation and maintenance of each type of persistent pain may provide insight into the mechanisms that underlie each of these pain states.

OBJECTIVE

To identify the effects of substance abuse status (active, former, and never) on utilization of highly active antiretroviral therapy (HAART), medication adherence, and virologic and immunologic responses to therapy.

METHODS

Prospective cohort study of 764 HIV-1-infected patients who attended an urban HIV clinic and participated in a standardized interview.

METHODS

Past utilization of HAART, self-reported nonadherence with antiretroviral therapy, and changes in HIV-1 RNA level and CD4+ lymphocyte count relative to prior peak and nadir, respectively.

RESULTS

Forty-four percent of active drug users failed to utilize HAART compared with 22% of former drug users and 18% of non-drug users (p <.001 for both comparisons). Among participants who were taking antiretroviral therapy when interviewed, active drug users were more likely to report medication nonadherence (34% vs. 24% of nonusers and 17% of former users), had a smaller median reduction in HIV-1 RNA from baseline (0.8 log10 copies/ml vs. 1.7 in nonusers and 1.6 in former users), and had smaller median increases in CD4+ lymphocyte count from baseline (65 cells/mm3 vs. 116 in nonusers and 122 in former users) (p <.05 for all comparisons with active users).

CONCLUSIONS

Active drug use was strongly associated with underutilization of HAART, nonadherence, and inferior virologic and immunologic responses to therapy, whereas former drug users and non-drug users were similar in all outcomes. Effective strategies are needed that integrate HIV-1 and substance abuse treatments.

Intracranial self-administration (ICSA) and intracranial place conditioning (ICPC) methodologies have been mainly used to study drug reward mechanisms, but they have also been applied toward examining brain reward mechanisms. ICSA studies in rodents have established that the ventral tegmental area (VTA) is a site supporting morphine and ethanol reinforcement. ICPC studies confirmed that injection of morphine into the VTA produces conditioned place preference (CPP). Further confirmation that activation of opioid receptors within the VTA is reinforcing comes from the findings that the endogenous opioid peptide met-enkephalin injected into the VTA produces CPP, and that the mu- and delta-opioid agonists, DAMGO and DPDPE, are self-infused into the VTA. Activation of the VTA dopamine (DA) system may produce reinforcing effects in general because (a) neurotensin is self-administered into the VTA, and injection of neurotensin into the VTA produces CPP and enhances DA release in the nucleus accumbens (NAC), and (b) GABA(A) antagonists are self-administered into the anterior VTA and injections of GABA(A) antagonists into the anterior VTA enhance DA release in the NAC. The NAC also appears to have a major role in brain reward mechanisms, whereas most data from ICSA and ICPC studies do not support an involvement of the caudate-putamen in reinforcement processes. Rodents will self-infuse a variety of drugs of abuse (e.g. amphetamine, morphine, phencyclidine and cocaine) into the NAC, and this occurs primarily in the shell region. ICPC studies also indicate that injection of amphetamine into the shell portion of the NAC produces CPP. Activation of the DA system within the shell subregion of the NAC appears to play a key role in brain reward mechanisms. Rats will ICSA the DA uptake blocker, nomifensine, into the NAC shell; co-infusion with a D2 antagonist can block this behavior. In addition, rats will self-administer a mixture of a D1 plus a D2 agonist into the shell, but not the core, region of the NAC. The ICSA of this mixture can be blocked with the co-infusion of either a D1 or a D2 antagonist. However, the interactions of other transmitter systems within the NAC may also play key roles because NMDA antagonists and the muscarinic agonist carbachol are self-infused into the NAC. The medial prefrontal (MPF) cortex supports the ICSA of cocaine and phencyclidine. The DA system also seems to play a role in this behavior since cocaine self-infusion into the MPF cortex can be blocked by co-infusing a D2 antagonist, or with 6-OHDA lesions of the MPF cortex. Limited studies have been conducted on other CNS regions to elucidate their role in brain and drug reward mechanisms using ICSA or ICPC procedures. Among these regions, ICPC findings suggest that cocaine and amphetamine are rewarding in the rostral ventral pallidum (VP); ICSA and ICPC studies indicate that morphine is rewarding in the dorsal hippocampus, central gray and lateral hypothalamus. Finally, substance P mediated systems within the caudal VP (nucleus basalis magnocellularis) and serotonin systems of the dorsal and median raphe nuclei may also be important anatomical components involved in brain reward mechanisms. Overall, the ICSA and ICPC studies indicate that there are a number of receptors, neuronal pathways, and discrete CNS sites involved in brain reward mechanisms.

We have obtained, for the first time, a quantitative protein expression profile of membrane transporters and receptors in human brain microvessels, that is, the blood-brain barrier (BBB). Brain microvessels were isolated from brain cortexes of seven males (16-77 years old) and protein expression of 114 membrane proteins was determined by means of a liquid chromatography-tandem mass spectrometric quantification method using recently established in-silico peptide selection criteria. Among drug transporters, breast cancer resistance protein showed the most abundant protein expression (8.14 fmol/μg protein), and its expression level was 1.85-fold greater in humans than in mice. By contrast, the expression level of P-glycoprotein in humans (6.06 fmol/μg protein) was 2.33-fold smaller than that of mdr1a in mice. The organic anion transporters reported in rodent BBB, that is, multidrug resistance-associated protein, organic anion transporter and organic anion-transporting polypeptide family members, were under limit of quantification in humans, except multidrug resistance-associated protein 4 (0.195 fmol/μg protein). Among detected transporters and receptors for endogenous substances, the glucose transporter 1 level was similar to that of mouse, while the L-type amino acid transporter 1 level was fivefold smaller than that of mouse. These findings should be useful for understanding human BBB function and its differences from that in mouse.

Inflammatory proteases (mast cell tryptase and trypsins) cleave protease-activated receptor 2 (PAR2) on spinal afferent neurons and cause persistent inflammation and hyperalgesia by unknown mechanisms. We determined whether transient receptor potential vanilloid receptor 1 (TRPV1), a cation channel activated by capsaicin, protons, and noxious heat, mediates PAR2-induced hyperalgesia. PAR2 was coexpressed with TRPV1 in small- to medium-diameter neurons of the dorsal root ganglia (DRG), as determined by immunofluorescence. PAR2 agonists increased intracellular [Ca2+] ([Ca2+]i) in these neurons in culture, and PAR2-responsive neurons also responded to the TRPV1 agonist capsaicin, confirming coexpression of PAR2 and TRPV1. PAR2 agonists potentiated capsaicin-induced increases in [Ca2+]i in TRPV1-transfected human embryonic kidney (HEK) cells and DRG neurons and potentiated capsaicin-induced currents in DRG neurons. Inhibitors of phospholipase C and protein kinase C (PKC) suppressed PAR2-induced sensitization of TRPV1-mediated changes in [Ca2+]i and TRPV1 currents. Activation of PAR2 or PKC induced phosphorylation of TRPV1 in HEK cells, suggesting a direct regulation of the channel. Intraplantar injection of a PAR2 agonist caused persistent thermal hyperalgesia that was prevented by antagonism or deletion of TRPV1. Coinjection of nonhyperalgesic doses of PAR2 agonist and capsaicin induced hyperalgesia that was inhibited by deletion of TRPV1 or antagonism of PKC. PAR2 activation also potentiated capsaicin-induced release of substance P and calcitonin gene-related peptide from superfused segments of the dorsal horn of the spinal cord, where they mediate hyperalgesia. We have identified a novel mechanism by which proteases that activate PAR2 sensitize TRPV1 through PKC. Antagonism of PAR2, TRPV1, or PKC may abrogate protease-induced thermal hyperalgesia.

Attention deficit hyperactivity disorder (ADHD) is a complex condition with environmental and genetic etiologies. Up to this point, research has identified genetic associations with candidate genes from known biological pathways. In order to identify novel ADHD susceptibility genes, 600,000 SNPs were genotyped in 958 ADHD proband-parent trios. After applying data cleaning procedures we examined 429,981 autosomal SNPs in 909 family trios. We generated six quantitative phenotypes from 18 ADHD symptoms to be used in genome-wide association analyses. With the PBAT screening algorithm, we identified 2 SNPs, rs6565113 and rs552655 that met the criteria for significance within a specified phenotype. These SNPs are located in intronic regions of genes CDH13 and GFOD1, respectively. CDH13 has been implicated previously in substance use disorders. We also evaluated the association of SNPs from a list of 37 ADHD candidate genes that was specified a priori. These findings, along with association P-values with a magnitude less than 10(-5), are discussed in this manuscript. Seventeen of these candidate genes had association P-values lower then 0.01: SLC6A1, SLC9A9, HES1, ADRB2, HTR1E, DDC, ADRA1A, DBH, DRD2, BDNF, TPH2, HTR2A, SLC6A2, PER1, CHRNA4, SNAPP-values lower than 0.01 and multiple association P-values at a magnitude of 10(-5) in this gene. In sum, these findings identify novel genetic associations at viable ADHD candidate genes and provide confirmatory evidence for associations at previous candidate genes. Replication of these results is necessary in order to confirm the proposed genetic variants for ADHD.

The subject of neuroinflammation is reviewed. In response to psychological stress or certain physical stressors, an inflammatory process may occur by release of neuropeptides, especially Substance P (SP), or other inflammatory mediators, from sensory nerves and the activation of mast cells or other inflammatory cells. Central neuropeptides, particularly corticosteroid releasing factor (CRF), and perhaps SP as well, initiate a systemic stress response by activation of neuroendocrinological pathways such as the sympathetic nervous system, hypothalamic pituitary axis, and the renin angiotensin system, with the release of the stress hormones (i.e., catecholamines, corticosteroids, growth hormone, glucagons, and renin). These, together with cytokines induced by stress, initiate the acute phase response (APR) and the induction of acute phase proteins, essential mediators of inflammation. Central nervous system norepinephrine may also induce the APR perhaps by macrophage activation and cytokine release. The increase in lipids with stress may also be a factor in macrophage activation, as may lipopolysaccharide which, I postulate, induces cytokines from hepatic Kupffer cells, subsequent to an enhanced absorption from the gastrointestinal tract during psychologic stress. The brain may initiate or inhibit the inflammatory process. The inflammatory response is contained within the psychological stress response which evolved later. Moreover, the same neuropeptides (i.e., CRF and possibly SP as well) mediate both stress and inflammation. Cytokines evoked by either a stress or inflammatory response may utilize similar somatosensory pathways to signal the brain. Other instances whereby stress may induce inflammatory changes are reviewed. I postulate that repeated episodes of acute or chronic psychogenic stress may produce chronic inflammatory changes which may result in atherosclerosis in the arteries or chronic inflammatory changes in other organs as well.

Alcohol dependence is a highly prevalent disorder that is associated with serious morbidity and mortality. Because the GABAA neurotransmitter receptor is an important mediator for several behavioral effects of alcohol, genes encoding GABA-related proteins are functional candidates to influence risk of alcohol dependence. Two genome-wide scans showed linkage of alcohol dependence to a region on chromosome 4p, which contains a cluster of genes encoding GABAA receptor subunits. A recent effort to fine map that region showed a haplotypic association of alcohol dependence to the gene encoding the GABAA receptor alpha-2 subunit (GABRA2). We examined 10 single nucleotide polymorphisms (SNPs) spanning the coding region of this gene in samples of European American subjects with alcohol dependence (n = 446), and controls (n = 334) screened to exclude substance use disorders. There was evidence of association to alcohol dependence for seven adjacent markers spanning 98,000 bp in the middle and 3'-portion of the GABRA2 gene (range of P-values = 0.008-0.03). When the subset of the alcohol-dependent subjects excluding those with a diagnosis of cocaine or opioid dependence or major depressive episode (n = 198) was examined, the strength of the association was increased across these 7 SNPs (range of P-values = 0.002-0.007). Two common haplotypes in this region accounted for 90.8% of chromosomes. The more common haplotype was present in 55.6% of control group chromosomes versus 48.2% of alcohol-dependent subjects (P = 0.007) and 45.8% of subjects with alcohol dependence but no co-morbid drug dependence or depression (P = 0.003). These findings replicate and extend recently reported findings, which together underscore the potential contribution of polymorphic variation at the GABRA2 locus to the risk for alcohol dependence.

BACKGROUND

The omega-3 (n-3) fatty acids docosahexaenoic acid and eicosapentaenoic acid, along with γ-linolenic acid and antioxidants, may modulate systemic inflammatory response and improve oxygenation and outcomes in patients with acute lung injury.

OBJECTIVE

To determine if dietary supplementation of these substances to patients with acute lung injury would increase ventilator-free days to study day 28.

METHODS

The OMEGA study, a randomized, double-blind, placebo-controlled, multicenter trial conducted from January 2, 2008, through February 21, 2009. Participants were 272 adults within 48 hours of developing acute lung injury requiring mechanical ventilation whose physicians intended to start enteral nutrition at 44 hospitals in the National Heart, Lung, and Blood Institute ARDS Clinical Trials Network. All participants had complete follow-up.

METHODS

Twice-daily enteral supplementation of n-3 fatty acids, γ-linolenic acid, and antioxidants compared with an isocaloric control. Enteral nutrition, directed by a protocol, was delivered separately from the study supplement.

METHODS

Ventilator-free days to study day 28.

RESULTS

The study was stopped early for futility after 143 and 129 patients were enrolled in the n-3 and control groups. Despite an 8-fold increase in plasma eicosapentaenoic acid levels, patients receiving the n-3 supplement had fewer ventilator-free days (14.0 vs 17.2; P = .02) (difference, -3.2 [95% CI, -5.8 to -0.7]) and intensive care unit-free days (14.0 vs 16.7; P = .04). Patients in the n-3 group also had fewer nonpulmonary organ failure-free days (12.3 vs 15.5; P = .02). Sixty-day hospital mortality was 26.6% in the n-3 group vs 16.3% in the control group (P = .054), and adjusted 60-day mortality was 25.1% and 17.6% in the n-3 and control groups, respectively (P = .11). Use of the n-3 supplement resulted in more days with diarrhea (29% vs 21%; P = .001).

CONCLUSIONS

Twice-daily enteral supplementation of n-3 fatty acids, γ-linolenic acid, and antioxidants did not improve the primary end point of ventilator-free days or other clinical outcomes in patients with acute lung injury and may be harmful.

BACKGROUND

clinicaltrials.gov Identifier: NCT00609180.

Antibodies to substance P with a high titer have been produced and used in immunohistochemical studies on the peripheral and central nervous system of the rat and the cat. Evidence was obtained for the localization of substance P in a certain population of primary sensory neurons, probably small nerve cells with unmyelinated processes. Substance P or a peptide similar to it was also observed in cell bodies in the medial habenula and in probable nerve terminals in many brain areas. The results give morphological support for a transmitter (or modulator) role of substance P in the nervous system.

Calcitonin gene-related peptide (CGRP) immunoreactivity was found throughout the entire spinal cord of man, marmoset, horse, pig, cat, guinea pig, mouse, rat, and frog. CGRP-immunoreactive fibers were most concentrated in the dorsal horn. In the ventral horn of some species large immunoreactive cells, tentatively characterized as motoneurons, were present. Pretreatment of rats with colchicine enhanced staining of these large cells but did not reveal CGRP-immunoreactive cell bodies in the dorsal horn. In the dorsal root ganglia, CGRP immunoreactivity was observed in most of the small and some of the intermediate sized cells. Substance P immunoreactivity, where present, was co-localized with CGRP to a proportion of the small cells. In the cat the ratio of substance P-immunoreactive to CGRP-immunoreactive ganglion cells was 1:2.7 (p less than 0.001). The concentration of CGRP-immunoreactive material in tissue extracts was determined by radioimmunoassay. In the dorsal horn of the rat spinal cord the levels of peptide were found to range from 225.7 +/- 30.0 pmol/gm of wet weight in the cervical region to 340.6 +/- 74.6 pmol/gm in the sacral spinal cord. In the rat ventral spinal cord, levels of 15.7 +/- 2.7 to 35.1 +/- 10.6 pmol/gm were found. The concentration in dorsal root ganglia of the lumbar region was 225.4 +/- 46.9 pmol/gm. Gel permeation chromatography of this extractable CGRP-like immunoreactivity revealed three distinct immunoreactive peaks, one eluting at the position of synthetic CGRP and the others, of smaller size, eluting later. In cats and rats, rhizotomy induced a marked loss of CGRP-immunoreactive fibers from the dorsal horn of the spinal cord. In the cat, unilateral lumbosacral dorsal rhizotomy resulted in a significant (p less than 0.05) reduction of extractable CGRP from the ipsilateral lumbar dorsal horn (5.6 +/- 1.2 pmol/gm of wet weight) compared to the contralateral side (105.0 +/- 36.0 pmol/gm of wet weight). We conclude that the major origin of CGRP in the dorsal spinal cord is extrinsic, from afferent fibers which are probably derived from cells in the dorsal root ganglia. The selective distribution of CGRP throughout sensory, motor, and autonomic areas of the spinal cord suggests many putative roles for this novel peptide.

BACKGROUND

Smoking remains a major public health problem. Twin studies indicate that the ability to quit smoking is substantially heritable, with genetics that overlap modestly with the genetics of vulnerability to dependence on addictive substances.

OBJECTIVE

To identify replicated genes that facilitate smokers' abilities to achieve and sustain abstinence from smoking (herein after referred to as quit-success genes) found in more than 2 genome-wide association (GWA) studies of successful vs unsuccessful abstainers, and, secondarily, to nominate genes for selective involvement in smoking cessation success with bupropion hydrochloride vs nicotine replacement therapy (NRT).

METHODS

The GWA results in subjects from 3 centers, with secondary analyses of NRT vs bupropion responders.

METHODS

Outpatient smoking cessation trial participants from 3 centers.

METHODS

European American smokers who successfully vs unsuccessfully abstain from smoking with biochemical confirmation in a smoking cessation trial using NRT, bupropion, or placebo (N = 550).

METHODS

Quit-success genes, reproducibly identified by clustered nominally positive single-nucleotide polymorphisms (SNPs) in more than 2 independent samples with significant P values based on Monte Carlo simulation trials. The NRT-selective genes were nominated by clustered SNPs that display much larger t values for NRT vs placebo comparisons. The bupropion-selective genes were nominated by bupropion-selective results.

RESULTS

Variants in quit-success genes are likely to alter cell adhesion, enzymatic, transcriptional, structural, and DNA, RNA, and/or protein-handling functions. Quit-success genes are identified by clustered nominally positive SNPs from more than 2 samples and are unlikely to represent chance observations (Monte Carlo P< .0003). These genes display modest overlap with genes identified in GWA studies of dependence on addictive substances and memory.

CONCLUSIONS

These results support polygenic genetics for success in abstaining from smoking, overlap with genetics of substance dependence and memory, and nominate gene variants for selective influences on therapeutic responses to bupropion vs NRT. Molecular genetics should help match the types and/or intensity of antismoking treatments with the smokers most likely to benefit from them.