Citations
All
Search in:AllTitleAbstractAuthor name
Publications
(20K+)
Patents
Grants
Pathways
Clinical trials
Publication
Journal: Biochemical Journal
February/10/1972
Abstract
1. Concentrations of cyclic AMP (adenosine 3':5'-cyclic monophosphate) and rates of insulin release were measured in islets of Langerhans isolated from rat pancreas and incubated for various times in the presence of glucose, 3-isobutyl-1-methylxanthine, caffeine, theophylline, adrenaline and diazoxide. 2. Caffeine and theophylline produced small but significant increases in both cyclic AMP and release of insulin when they were incubated in the presence of 10mm-glucose. 3. 3-Isobutyl-1-methylxanthine produced a marked increase in the intracellular concentration of cyclic AMP in the presence of 5mm- and 10mm-glucose. However, insulin release was stimulated only in the presence of 10mm-glucose. 4. In response to rising concentrations of extracellular glucose (5-20mm) there was no detectable increase in the intracellular concentration of cyclic AMP even though there was a marked increase in the rate of insulin release. 5. In response to 10mm-glucose insulin release occurred in two phases and 3-isobutyl-1-methylxanthine potentiated the effect of glucose on both phases. The intracellular concentration of cyclic AMP remained constant with glucose and rose within 10min to its maximum value with 3-isobutyl-1-methylxanthine. 6. Adrenaline and diazoxide inhibited insulin release and lowered the intracellular concentration of cyclic AMP when islets were incubated with glucose or 3-isobutyl-1-methylxanthine. 7. It is suggested that glucose does not stimulate insulin release by increasing the concentration of cyclic AMP in islet cells. However, the concentration of cyclic AMP in islet cells may modulate the effect of glucose on the release process.
Publication
Journal: Resuscitation
January/24/2012
Abstract
BACKGROUND
There is little evidence from clinical trials that the use of adrenaline (epinephrine) in treating cardiac arrest improves survival, despite adrenaline being considered standard of care for many decades. The aim of our study was to determine the effect of adrenaline on patient survival to hospital discharge in out of hospital cardiac arrest.
METHODS
We conducted a double blind randomised placebo-controlled trial of adrenaline in out-of-hospital cardiac arrest. Identical study vials containing either adrenaline 1:1000 or placebo (sodium chloride 0.9%) were prepared. Patients were randomly allocated to receive 1 ml aliquots of the trial drug according to current advanced life support guidelines. Outcomes assessed included survival to hospital discharge (primary outcome), pre-hospital return of spontaneous circulation (ROSC) and neurological outcome (Cerebral Performance Category Score - CPC).
RESULTS
A total of 4103 cardiac arrests were screened during the study period of which 601 underwent randomisation. Documentation was available for a total of 534 patients: 262 in the placebo group and 272 in the adrenaline group. Groups were well matched for baseline characteristics including age, gender and receiving bystander CPR. ROSC occurred in 22 (8.4%) of patients receiving placebo and 64 (23.5%) who received adrenaline (OR=3.4; 95% CI 2.0-5.6). Survival to hospital discharge occurred in 5 (1.9%) and 11 (4.0%) patients receiving placebo or adrenaline respectively (OR=2.2; 95% CI 0.7-6.3). All but two patients (both in the adrenaline group) had a CPC score of 1-2.
CONCLUSIONS
Patients receiving adrenaline during cardiac arrest had no statistically significant improvement in the primary outcome of survival to hospital discharge although there was a significantly improved likelihood of achieving ROSC.
Publication
Journal: Science
December/7/1968
Abstract
The pacemaker potential in Purkinje fibers is generated by a slow fall in potassium current which allows the inward background currents to depolarize the membrane. Adrenaline shifts the relation between activation of the potassium current and membrane potential in a depolarizing direction. Consequently, during the pacemaker potential, the potassium current falls more rapidly to lower values and the inward currents then depolarize the membrane more quickly. The shift in the potassium activation curve produced by adrenaline is large compared to that produced by calcium ions. The molecular action of adrenaline may involve either a large change in the surface charge of the membrane or a change in the dependence of the potassium permeability on the local electric field.
Publication
Journal: Biochemical Journal
June/11/1985
Abstract
At maximally effective concentrations, vasopressin (10(-7) M) increased myo-inositol trisphosphate (IP3) in isolated rat hepatocytes by 100% at 3 s and 150% at 6 s, while adrenaline (epinephrine) (10(-5) M) produced a 17% increase at 3 s and a 30% increase at 6 s. These increases were maintained for at least 10 min. Both agents increased cytosolic free Ca2+ [( Ca2+]i) maximally by 5 s. Increases in IP3 were also observed with angiotensin II and ATP, but not with glucagon or platelet-activating factor. The dose-responses of vasopressin and adrenaline on phosphorylase and [Ca2+]i showed a close correspondence, whereas IP3 accumulation was 20-30-fold less sensitive. However, significant (20%) increases in IP3 could be observed with 10(-9) M-vasopressin and 10(-7) M-adrenaline, which induce near-maximal phosphorylase activation. Vasopressin-induced accumulation of IP3 was potentiated by 10mM-Li+, after a lag of approx. 1 min. However the rise in [Ca2+]i and phosphorylase activation were not potentiated at any time examined. Similar data were obtained with adrenaline as agonist. Lowering the extracellular Ca2+ to 30 microM or 250 microM did not affect the initial rise in [Ca2+]i with vasopressin but resulted in a rapid decline in [Ca2+]i. Brief chelation of extracellular Ca2+ for times up to 4 min also did not impair the rate or magnitude of the increase in [Ca2+]i or phosphorylase a induced by vasopressin. The following conclusions are drawn from these studies. IP3 is increased in rat hepatocytes by vasopressin, adrenaline, angiotensin II and ATP. The temporal relationships of its accumulation to the increases in [Ca2+]i and phosphorylase a are consistent with it playing a second message role. Influx of extracellular Ca2+ is not required for the initial rise in [Ca2+]i induced by these agonists, but is required for the maintenance of the elevated [Ca2+]i.
Publication
Journal: Proceedings of the Royal Society of London. Series B, Biological sciences
April/25/1969
Publication
Journal: European Journal of Pharmacology
March/3/1999
Abstract
In this review, subtypes of functional alpha1- and alpha2-adrenoceptors are discussed. These are cell membrane receptors, belonging to the seven transmembrane spanning G-protein-linked family of receptors, which respond to the physiological agonists noradrenaline and adrenaline. Alpha1-adrenoceptors can be divided into alpha1A-, alpha1B- and alpha1D-adrenoceptors, all of which mediate contractile responses involving Gq/11 and inositol phosphate turnover. A 4th alpha1-adrenoceptor, the alpha1L-, has been postulated to mediate contractions in some tissues, but its relationship to cloned receptors remains to be established. Alpha2-adrenoceptors can be divided into alpha2A-, alpha2B- and alpha2C-adrenoceptors, all of which mediate contractile responses. Prejunctional inhibitory alpha2-adrenoceptors are predominantly of the alpha2A-adrenoceptor subtype (the alpha2D-adrenoceptor is a species orthologue), although alpha2C-adrenoceptors may also occur prejunctionally. Although alpha2-adrenoceptors are linked to inhibition of adenylate cyclase, this may not be the primary signal in causing smooth muscle contraction; likewise, prejunctional inhibitory actions probably involve restriction of Ca2+ entry or opening of K+ channels. Receptor knock-out mice are beginning to refine our knowledge of the functions of alpha-adrenoceptor subtypes.
Publication
Journal: Journal of Physiology
January/6/1983
Abstract
1. Effects of digitalis compounds on slow inward Ca current I(si)) and contractile force were examined in ferret ventricular muscle (single sucrose-gap voltage clamp) and calf Purkinje fibres (two micro-electrode voltage clamp).2. In ventricular muscle, ouabain increased I(si) and inward current tails associated with I(si) conductance. The enhancement of I(si) followed a time course similar to the development of the positive inotropic effect, and it could be observed in the absence of aftercontractions or other signs of toxicit.3. The response of myocardial I(si) and twitch force to ouabain depended strongly on a previous history of driven action potentials.4. Veratridine, a toxin that promotes Na entry through tetrodotoxin-sensitive channels, also increased I(si) and twitch force in driven ventricular muscle preparations.5. The effects of ouabain, action potential stimulation and veratridine are consistent with reported effects of K-poor solutions in indicating that elevation of intracellular Na can lead to enhancement of I(si). Additional experiments suggest that the link between Na(i) and I(si) involves intracellular Ca.6. When Cs-loaded Purkinje fibres were bathed in solutions containing Sr instead of Ca, enhancement of I(si) by strophanthidin was abolished even though a positive inotropic response persisted.7. After intracellular injection of Purkinje fibres with EGTA, I(si) no longer increased with strophanthidin, although it remained responsive to adrenaline.8. Clear-cut increases in I(si) were seen in Cs-loaded Purkinje fibres even at very low concentrations of strophanthidin (20-50 nM), where the occurence of Na pump inhibition has been questioned.9. Positive regulation of Ca entry by intracellular Ca may act as a facilitory mechanism that amplifies myocardial responsiveness to digitalis and other inotropic interventions. Through changes in I(si), small rises in diastolic free Ca might lead to large increases in the activator Ca transient during contraction.
Publication
Journal: Journal of Clinical Investigation
July/9/1987
Abstract
Hypoalbuminemia in inflammatory disorders is not an infrequent finding. However, little is known about albumin synthesis in these patients. In the present study we have measured the albumin synthesis in four patients with inflammatory diseases using the [14C]carbonate technique. Because inflammation causes a decreased albumin synthesis and this decreased synthesis could not be related to a reduced amino acid supply, we have also examined the possible molecular mechanisms of reduced albumin synthesis during inflammation using in vivo and in vitro experiments in rats. In rats with turpentine-induced inflammation, serum albumin concentration and liver albumin mRNa level were markedly decreased. These changes could not be reproduced by administration of fibrinogen-, or fibrin-degradation products, or several hormones, such as corticosteroids, growth hormone, and adrenaline. However, monocytic products, especially interleukin 1, postulated to be important mediators of the inflammatory response, reduced albumin synthesis and liver albumin messenger RNA content but not total protein synthesis in rats in vivo and in primary cultures of rat hepatocytes. These findings suggest that monocytic products play an important role in reduced albumin synthesis during inflammation.
Publication
Journal: Journal of Allergy and Clinical Immunology
April/8/2010
Abstract
Anaphylaxis occurs commonly in community settings. The rate of occurrence is increasing, especially in young people. Understanding potential triggers, mechanisms, and patient-specific risk factors for severity and fatality is the key to performing appropriate risk assessment in those who have previously experienced an acute anaphylactic episode. The diagnosis of anaphylaxis is based primarily on clinical criteria and is valid even if the results of laboratory tests, such as serum total tryptase levels, are within normal limits. Positive skin test results or increased serum specific IgE levels to potential triggering allergens confirm sensitization but do not confirm the diagnosis of anaphylaxis because asymptomatic sensitization is common in the general population. Important patient-related risk factors for severity and fatality include age, concomitant diseases, and concurrent medications, as well as other less well-defined factors, such as defects in mediator degradation pathways, fever, acute infection, menses, emotional stress, and disruption of routine. Prevention of anaphylaxis depends primarily on optimal management of patient-related risk factors, strict avoidance of confirmed relevant allergen or other triggers, and, where indicated, immunomodulation (eg, subcutaneous venom immunotherapy to prevent Hymenoptera sting-triggered anaphylaxis, an underused, potentially curative treatment). The benefits and risks of immunomodulation to prevent food-triggered anaphylaxis are still being defined. Epinephrine (adrenaline) is the medication of first choice in the treatment of anaphylaxis. All patients at risk for recurrence in the community should be equipped with 1 or more epinephrine autoinjectors; a written, personalized anaphylaxis emergency action plan; and up-to-date medical identification. Improvements in the design of epinephrine autoinjectors will help to optimize ease of use and safety. Randomized controlled trials of pharmacologic agents, such as antihistamines and glucocorticoids, are needed to strengthen the evidence base for treatment of acute anaphylactic episodes.
Publication
Journal: Allergy: European Journal of Allergy and Clinical Immunology
October/16/2007
Abstract
Anaphylaxis is a growing paediatric clinical emergency that is difficult to diagnose because a consensus definition was lacking until recently. Many European countries have no specific guidelines for anaphylaxis. This position paper prepared by the EAACI Taskforce on Anaphylaxis in Children aims to provide practical guidelines for managing anaphylaxis in childhood based on the limited evidence available. Intramuscular adrenaline is the acknowledged first-line therapy for anaphylaxis, in hospital and in the community, and should be given as soon as the condition is recognized. Additional therapies such as volume support, nebulized bronchodilators, antihistamines or corticosteroids are supplementary to adrenaline. There are no absolute contraindications to administering adrenaline in children. Allergy assessment is mandatory in all children with a history of anaphylaxis because it is essential to identify and avoid the allergen to prevent its recurrence. A tailored anaphylaxis management plan is needed, based on an individual risk assessment, which is influenced by the child's previous allergic reactions, other medical conditions and social circumstances. Collaborative partnerships should be established, involving school staff, healthcare professionals and patients' organizations. Absolute indications for prescribing self-injectable adrenaline are prior cardiorespiratory reactions, exercise-induced anaphylaxis, idiopathic anaphylaxis and persistent asthma with food allergy. Relative indications include peanut or tree nut allergy, reactions to small quantities of a given food, food allergy in teenagers and living far away from a medical facility. The creation of national and European databases is expected to generate better-quality data and help develop a stepwise approach for a better management of paediatric anaphylaxis.
Publication
Journal: Current Drug Metabolism
November/17/2008
Abstract
Neuropsychiatric symptoms like mood changes and depression are common in patients with chronic inflammatory disorders such as infections, autoimmune diseases or cancer. The pathogenesis of these symptoms is still unclear. Pro-inflammatory stimuli interfere not only with the neural circuits and neurotransmitters of the serotonergic, but also with those of the adrenergic system. The pro-inflammatory cytokine interferon-gamma stimulates the biosynthesis of 5,6,7,8-tetrahydrobiopterin (BH4), which is cofactor for several aromatic amino acid monooxygenases and thus is strongly involved in the biosynthesis of the neurotransmitter serotonin and the catecholamines dopamine, epinephrine (adrenaline) and norepinephrine (noradrenaline). In macrophages, interferon-gamma also triggers the high output of reactive oxygen species, which can destroy the oxidation-labile BH4. Recent data suggest that oxidative loss of BH4 in chronic inflammatory conditions can reduce the biosynthesis of catecholamines, which may relate to disturbed adrenergic neurotransmitter pathways in patients.
Publication
Journal: Molecular and Cellular Neurosciences
July/7/2005
Abstract
Microglial cells are the immune-competent elements of the brain. They not only express receptors for chemokines and cytokines but also for neurotransmitters such as GABA [Charles et al., Mol. Cell Neurosci. 24 (2003) 214], glutamate [Noda et al., J. Neurosci. 20 (2000) 251], and adrenaline [Mori et al., Neuropharmacology 43 (2002) 1026]. Here we report the functional expression of dopamine receptors in mouse and rat microglia, in culture and brain slices. Using the patch clamp technique as the functional assay we identified D1- and D2-like dopamine receptors using subtype-specific ligands. They triggered the inhibition of the constitutive potassium inward rectifier and activated potassium outward currents in a subpopulation of microglia. Chronic dopamine receptor stimulation enhanced migratory activity and attenuated the lipopolysaccharide (LPS)-induced nitric oxide (NO) release similar as by stimulation of adrenergic receptors. While, however, noradrenaline attenuated the LPS-induced release of TNF-alpha and IL-6, dopamine was ineffective in modulating this response. We conclude that microglia express dopamine receptors which are distinct in function from adrenergic receptors.
Publication
Journal: Biochemical Journal
September/2/1974
Abstract
The transport and oxidation of glucose, the content of fructose 1,6-diphosphate, and the release of insulin were studied in microdissected pancreatic islets of ob/ob mice incubated in Krebs-Ringer bicarbonate medium. Under control conditions glucose oxidation and insulin release showed a similar dependence on glucose concentration with the steepest slope in the range 5-12mm. The omission of Ca(2+), or the substitution of choline ions for Na(+), or the addition of diazoxide had little if any effect on glucose transport. However, Ca(2+) or Na(+) deficiency as well as diazoxide (7-chloro-3-methyl-1,2,4-benzothiadiazine 1,1-dioxide) or ouabain partially inhibited glucose oxidation. These alterations of medium composition also increased the islet content of fructose 1,6-diphosphate, as did the addition of adrenaline. Phentolamine [2-N-(3-hydroxyphenyl)-p-toluidinomethyl-2-imidazoline] counteracted the effects of adrenaline and Ca(2+) deficiency on islet fructose 1,6-diphosphate. After equilibration in Na(+)-deficient medium, the islets exhibited an increase in basal insulin release whereas the secretory response to glucose was inhibited. The inhibitory effects of Na(+) deficiency on the secretory responses to different concentrations of glucose correlated with those on (14)CO(2) production. When islets were incubated with 17mm-glucose, the sudden replacement of Na(+) by choline ions resulted in a marked but transient stimulation of insulin release that was not accompanied by a demonstrable increase of glucose oxidation. Galactose and 3-O-methylglucose had no effect on glucose oxidation or on insulin release. The results are consistent with a metabolic model of the beta-cell recognition of glucose as insulin secretagogue and with the assumption that Ca(2+) or Na(+) deficiency, or the addition of adrenaline or diazoxide, inhibit insulin release at some step distal to stimulus recognition. In addition the results suggest that these conditions create a partial metabolic block of glycolysis in the beta-cells. Hence the interrelationship between the processes of stimulus recognition and insulin discharge may involve a positive feedback of secretion on glucose metabolism.
Publication
Journal: American Journal of Hypertension
April/11/2012
Abstract
BACKGROUND
The question of whether reduced sodium intake is effective as a health prophylaxis initiative is unsolved. The purpose was to estimate the effects of low-sodium vs. high-sodium intake on blood pressure (BP), renin, aldosterone, catecholamines, and lipids.
METHODS
Studies randomizing persons to low-sodium and high-sodium diets evaluating at least one of the above outcome parameters were included. Data were analyzed with Review Manager 5.1.
RESULTS
A total of 167 studies were included. The effect of sodium reduction in: (i) Normotensives: Caucasians: systolic BP (SBP) -1.27 mm Hg (95% confidence interval (CI): -1.88, -0.66; P = 0.0001), diastolic BP (DBP) -0.05 mm Hg (95% CI: -0.51, 0.42; P = 0.85). Blacks: SBP -4.02 mm Hg (95% CI: -7.37, -0.68; P = 0.002), DBP -2.01 mm Hg (95% CI: -4.37, 0.35; P = 0.09). Asians: SBP -1.27 mm Hg (95% CI: -3.07, 0.54; P = 0.17), DBP -1.68 mm Hg (95% CI: -3.29, -0.06; P = 0.04). (ii) Hypertensives: Caucasians: SBP -5.48 mm Hg (95% CI: -6.53, -4.43; P < 0.00001), DBP -2.75 mm Hg (95% CI: -3.34, -2.17; P < 0.00001). Blacks: SBP -6.44 mm Hg (95% CI: -8.85, -4.03; P = 0.00001), DBP -2.40 mm Hg (95% CI: -4.68, -0.12; P = 0.04). Asians: SBP -10.21 mm Hg (95% CI: -16.98, -3.44; P = 0.003), DBP -2.60 mm Hg (95% CI: -4.03, -1.16; P = 0.0004). Sodium reduction resulted in significant increases in renin (P < 0.00001), aldosterone (P < 0.00001), noradrenaline (P < 0.00001), adrenaline (P < 0.0002), cholesterol (P < 0.001), and triglyceride (P < 0.0008).
CONCLUSIONS
Sodium reduction resulted in a significant decrease in BP of 1% (normotensives), 3.5% (hypertensives), and a significant increase in plasma renin, plasma aldosterone, plasma adrenaline, and plasma noradrenaline, a 2.5% increase in cholesterol, and a 7% increase in triglyceride.
Publication
Journal: British Journal of Clinical Pharmacology
June/12/1981
Abstract
1 A new technique for determining venous compliance at a standardized congestion pressure has been developed based on the optical method described by Nachev, Collier & Robinson (1971). It uses a linear variable differential transformer for a direct and continuous recording of venous compliance. 2 This method has been used to establish dose-response curves for the constrictor effects of noradrenaline, adrenaline, 5-hydroxytryptamine and dihydroergotamine after direct local infusion. 3 A parallel shift to the right of the noradrenaline dose-response curves was observed after local infusion of phentolamine, showing that the method can be used also to study interactions between agonists and antagonists on human veins in vivo. The usefulness of this technique for investigating the effects of orally administered drugs has also been established. The venoconstrictor action of dihydroergotamine reached its maximum after 1.5 h and remained almost constant for the period of observation (8 h).
Authors
Publication
Journal: Pflugers Archiv European Journal of Physiology
May/23/1978
Abstract
1. The capacity ofr thermoregulation and thermogenesis in lean and genetically obese (ob/ob) mice has been investigated. 2. At 4 degrees C ob/ob mice rapidly die of hypothermia, because of a reduced capacity for cold-induced thermogenesis, but the animals are able to survive if previously adapted to 12 degrees C. 3. At all environmental temperatures between 30 degrees C and 10 degrees C the body temperature of ob/ob mice is 2.0-2.5 degrees C below that of lean animals. This may be due to a lower "setting" for body temperature. 4. At 34 degrees C the oxygen consumption of obese mice is greater than that of the lean animals while at 30 degrees C it is similar. When the environmental temperature is below 30 degrees C the oxygen consumption of the lean mice is greater. The obese animals therefore expend less energy on thermoregulatory thermogenesis. 5. The capacity for non-shivering thermogenesis was measured in lean and obese mice by investigating the effect of an injection of L-nor-adrenaline (1000 microgram/kg body weight) on the metabolic rate at 31 degrees C. Non-shivering thermogenesis was reduced by one-half in the obese animals. 6. One cause of the obesity of the ob/ob mouse is its high metabolic efficiency. We suggest that this high metabolic efficiency is due, at least in part, to less energy being expended on thermoregulatory thermogenesis.
Publication
Journal: Journal of Physiology
July/8/1981
Abstract
1. Properties of the 'pace-maker' current if in rabbit sino-atrial node have been investigated by voltage clamp of small preparations and compared with those of the iK2 current in the Purkinje fibre. Besides having a similar voltage range of activation and responding in a similar way to adrenaline, if resembles iK2 in other respects. 2. When external Na is reduced, if decreases proportionally. In 25% Na the time-dependent current change due to if disappears. 3. 20 mM-Cs completely abolishes it. 4. The time constant of if during a hyperpolarizing voltage-clamp pulse displays a relatively high temperature dependence. 5. In spite of the similarities between the two current systems, experiments in high K solutions (48 mM) rule out the possibility that the current change seen on a hyperpolarization reflects the decay of a pure K current. 6. From conductance measurements during onset of if it is deduced that if behaves as an inward current activated by hyperpolarizations.
Publication
Journal: Circulation
September/6/1989
Abstract
This study provides data on plasma hormone levels in patients with severe clinical congestive cardiac failure who had never received therapy and in whom the presence of an accumulation of excess water and sodium had been established. Eight patients were studied; two had ischemic cardiac disease, and six had dilated cardiomyopathy. Mean hemodynamic measurements at rest were as follows: cardiac index, 1.8 l/min/m2; pulmonary wedge pressure, 30 mm Hg; right atrial pressure, 15 mm Hg. Total body water content was 16% above control, extracellular liquid was 33% above control, plasma volume was 34% above control, total exchangeable sodium was 37% above control, renal plasma flow was 29% of control, and glomerular filtration rate was 65% of control. Plasma norepinephrine was consistently increased (on average 6.3 times control), whereas adrenaline was unaffected. Although plasma renin activity and aldosterone varied widely, they were on average above normal (renin 9.5 times control, aldosterone 6.4 times control). Plasma atrial natriuretic peptide (14.3 times control) and growth hormone (11.5 times control) were consistently increased. Cortisol was also increased on average (1.7 times control). Vasopressin was increased only in one patient.
Publication
Journal: Journal of Physiology
June/24/2009
Abstract
The purpose of the present investigation was to explore the effects of exercise and adrenaline on the mRNA expression of PGC-1alpha, a master regulator of mitochondrial biogenesis, in rat abdominal adipose tissue. We hypothesized that (1) exercise training would increase PGC-1alpha mRNA expression in association with increases in mitochondrial marker enzymes, (2) adrenaline would increase PGC-1alpha mRNA expression and (3) the effect of exercise on PGC-1alpha mRNA expression in white adipose tissue would be attenuated by a beta-blocker. Two hours of daily swim training for 4 weeks led to increases in mitochondrial marker proteins and PGC-1alpha mRNA expression in epididymal and retroperitoneal fat depots. Additionally, a single 2 h bout of exercise led to increases in PGC-1alpha mRNA expression immediately following exercise cessation. Adrenaline treatment of adipose tissue organ cultures led to dose-dependent increases in PGC-1alpha mRNA expression. A supra-physiological concentration of adrenaline increased PGC-1alpha mRNA expression in epididymal but not retroperitoneal adipose tissue. beta-Blockade attenuated the effects of an acute bout of exercise on PGC-1alpha mRNA expression in epididymal but not retroperitoneal fat pads. In summary, this is the first investigation to demonstrate that exercise training, an acute bout of exercise and adrenaline all increase PGC-1alpha mRNA expression in rat white adipose tissue. Furthermore it would appear that increases in circulating catecholamine levels may be one potential mechanism mediating exercise induced increases in PGC-1alpha mRNA expression in rat abdominal adipose tissue.
Publication
Journal: British Journal of Pharmacology
August/16/1995
Abstract
1. Lipopolysaccharide (LPS) co-induces nitric oxide synthase (iNOS) and cyclo-oxygenase (COX-2) in J774.2 macrophages. Here we have used LPS-activated J774.2 macrophages to investigate the effects of exogenous or endogenous nitric oxide (NO) on COX-2 in both intact and broken cell preparations. NOS activity was assessed by measuring the accumulation of nitrite using the Griess reaction. COX-2 activity was assessed by measuring the formation of 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) by radioimmunoassay. Western blot analysis was used to determine the expression of COX-2 protein. We have also investigated whether endogenous NO regulates the activity and/or expression of COX in vivo by measuring NOS and COX activity in the lung and kidney, as well as release of prostanoids from the perfused lung of normal and LPS-treated rats. 2. Incubation of cultured murine macrophages (J774.2 cells) with LPS (1 microgram ml-1) for 24 h caused a time-dependent accumulation of nitrite and 6-keto-PGF1 alpha in the cell culture medium which was first significant after 6 h. The formation of both 6-keto-PGF1 alpha and nitrite elicited by LPS was inhibited by cycloheximide (1 microM) or dexamethasone (1 microM). Western blot analysis showed that J774.2 macrophages contained COX-2 protein after LPS administration, whereas untreated cells contained no COX-2. 3. The accumulation of 6-keto-PGF1 alpha in the medium of LPS-activated J774.2 macrophages was concentration-dependently inhibited by chronic (24 h) exposure to sodium nitroprusside (SNP; 1-1000 microM). Sodium nitroprusside (1-1000 microM) also acutely (30 min) inhibited COX-2 activity in broken cell preparations of LPS-activated (12 h) J774.2 macrophages, in a similar concentration dependent manner. Addition of adrenaline (5 mM) and glutathione (0.1 mM) increased the activity of COX-2 in broken cell preparations. In the presence of these co-factors, SNP inhibited prostanoid production only at the highest concentration used (1 mM). When J774.2 cells were incubated in the presence of LPS (1 microg ml-1) and NG-monomethyl-L-arginine (L-NMMA: 1 mM) for 12 h, SNP at the highest concentration used (1 mM) acutely (30 min) inhibited the activity of COX-2 in cell homogenates with co-factors. However, when J774.2 macrophages were incubated for 24 or 12 h with LPS (1 microg ml-1)and L-NMMA (1 mM), the addition of SNP (0.001-1I000 microM) increased in a concentration-dependent manner the accumulation of 6-keto-PGF1a in intact cells (measured at 24 h) and COX-2 activity in cell homogenates in the presence of co-factors (determined at 12 h). SNP (1 mM; together with LPS for 12 h)decreased the amount of COX-2 protein induced by LPS in J774.2 macrophages.4. Indomethacin (30 1AM) abolished the formation of 6-keto-PGFa by LPS-activated macrophages, but had no effect on the release of nitrite. Conversely, L-NMMA, at the highest concentrations used (1 and 10 mM), increased the release of 6-keto-PGFIa an effect which was reversed by excess L-arginine (3 mM)but not by D-arginine. Similarly, the decrease in nitrite formation caused by L-NMMA was partially reversed by L-arginine (3 mM), but not by D-arginine. L-NMMA (10 mM; together with LPS for 12 h)increased the amount of COX-2 protein induced by LPS in J774.2 macrophages.5. In separate experiments, J774.2 macrophages were activated with LPS (1 microg ml-1), and L-NMMA(10 mM) was added for various times (0.5-24 h) before the collection of mediun at 24 h. L-NMMAenhanced the release of 6-keto-PGFI,, in a time-dependent manner, with the maximal enhancement seen when the NOS inhibitor was incubated with the cells for 24 h. 6. In experiments on male Wistar rats, we investigated the effect of L-NMMA on the release of prostanoids (6-keto-PGF1a prostaglandin E2, thromboxane B2) elicited by arachidonic acid (AA,30nmol) from ex vivo perfused kidneys and lungs. The release from the organs from normal and LPS-treated rats was unaffected by L-NMMA intraperitoneally (30 mg kg-1) for 6 h together with LPS(5 mg kg-1) or LPS vehicle. Similarly, acute (5 min) in vitro exposure to L-NMMA (1 mM) of the perfused organs from control and LPS-treated animals did not change the release of prostanoids elicited by AA (30 nmol).7. These results show that LPS causes the induction of iNOS and COX-2 in J774.2 macrophages. The co-release of NO and PGI2 induced by LPS is dependent on protein synthesis and occurs after a lag-time of 6-12 h. The formation of COX metabolites has no effect on NOS activity whereas NO inhibits both COX-2 activity and induction. These results demonstrate that NOS and COX can be co-induced in vitro and that under these conditions large amounts of NO inhibit the degree of COX expression and activity.In the absence of endogenous NO, lesser amounts of exogenous NO increase the activity of COX-2. In those situations in vivo when the level of NO induction is relatively low, NO does not regulate the increased activity of COX.
Publication
Journal: Allergy: European Journal of Allergy and Clinical Immunology
October/21/2009
Abstract
BACKGROUND
Peanut allergy is common, potentially severe and rarely resolves causing impaired quality of life. No disease-modifying treatment exists and there is therefore a need to develop a therapeutic intervention.
OBJECTIVE
The aim of this study was to investigate whether peanut oral immunotherapy (OIT) can induce clinical tolerance to peanut protein.
METHODS
Four peanut-allergic children underwent OIT. Preintervention oral challenges were performed to confirm clinical allergy and define the amount of protein required to cause a reaction (dose thresholds). OIT was then administered as daily doses of peanut flour increasing from 5 to 800 mg of protein with 2-weekly dose increases. After 6 further weeks of treatment, the oral challenge was repeated to define change in dose threshold and subjects continued daily treatment.
RESULTS
Preintervention challenges confirmed peanut allergy and revealed dose thresholds of 5-50 mg (1/40-1/4 of a whole peanut); one subject had anaphylaxis during challenge and required adrenaline injection. All subjects tolerated immunotherapy updosing to 800 mg protein and i.m. adrenaline was not required. Each subject tolerated at least 10 whole peanuts (approximately 2.38 g protein) in postintervention challenges, an increase in dose threshold of at least 48-, 49-, 55- and 478-fold for the four subjects.
CONCLUSIONS
We demonstrated a substantial increase in dose threshold after OIT in all subjects, including the subject with proven anaphylaxis. OIT was well tolerated and conferred protection against at least 10 peanuts, more than is likely to be encountered during accidental ingestion.
Publication
Journal: Journal of Physiology
June/30/2000
Publication
Journal: Journal of Trauma and Acute Care Surgery
September/16/2012
Abstract
BACKGROUND
There is emerging evidence that early trauma-induced coagulopathy (TIC) is mechanistically linked to disruption of the vascular endothelium and its glycocalyx, assessed by thrombomodulin and syndecan 1, respectively. This study evaluated if degradation of the endothelial glycocalyx and ensuing release of its heparin-like substances induce autoheparinization and thereby contributes to TIC.
METHODS
Prospective observational study of 77 trauma patients admitted to a Level I trauma center having blood sampled at admission. Data on demography, hematology, Injury Severity Score, transfusion requirements, 30-day mortality, and thrombelastography (TEG, concurrent kaolin-activated/kaolin-heparinase-activated) were recorded. Retrospective analysis of plasma/serum for biomarkers reflecting endothelial glycocalyx and cell damage (syndecan 1, thrombomodulin), tissue injury (histone-complexed DNA fragments), sympathoadrenal activation (adrenaline, noradrenaline), coagulation activation/anticoagulation (prothrombin fragment 1+2, fibrinogen, von Willebrand factor, factor XIII, antithrombin, protein C, activated protein C, tissue factor pathway inhibitor), fibrinolysis (tissue-type plasminogen activator, plasminogen activator inhibitor 1) and inflammation (interleukin 6, terminal complement complex). Stratification of patients was according to the degree of TEG-measured heparinization.
RESULTS
Four patients (5.2%) displayed evidence of high-degree autoheparinization, and these patients had higher Injury Severity Score (median [interquartile range], 31 [26-37] vs. 17 [10-26]), increased glucose (median, 13.6 vs. 8.0 mmol/L), and lower hemoglobin level (median, 5.8 vs. 8.4 mmol/L) and received more transfusions during the first 1 hour (median, 5 vs. 0) and 24 hours (median, 10 vs. 0) (all p < 0.05). Importantly, patients with autoheparinization had fourfold higher syndecan 1 levels (median [interquartile range], 116 ng/mL [78-140 ng/mL] vs. 31 ng/mL [18-49 ng/mL]), and they had higher international normalized ratio (median, 1.4 vs. 1.1), thrombomodulin (median, 4.1 vs. 1.7 ng/mL) and interleukin 6 (median, 129 vs. 71 pg/mL) but lower protein C (85% vs. 109%) (all p < 0.05), indicating profound endothelial damage, coagulopathy and inflammation.
CONCLUSIONS
Five percent of the patients with trauma in the present study had evidence of acute endogenous coagulopathy with autoheparinization by TEG, which appeared mechanistically linked to endothelial glycocalyx degradation. Acute endogenous autoheparinization may contribute to TIC.
METHODS
Prognostic study, level III.
Publication
Journal: Cochrane Database of Systematic Reviews
February/9/2011
Abstract
BACKGROUND
This is an update of a Cochrane Review first published in The Cochrane Library in Issue 2, 2003.Allergic rhinitis is a common condition which can significantly impair quality of life. Immunotherapy by injection can significantly reduce symptoms and medication use but its use is limited by the possibility of severe systemic adverse reactions. Immunotherapy by the sublingual route is therefore of considerable interest.
OBJECTIVE
To evaluate the efficacy and safety of sublingual immunotherapy for allergic rhinitis in adults and children.
METHODS
We searched the Cochrane ENT Group Trials Register; CENTRAL (2010, Issue 3); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; mRCT and additional sources for published and unpublished trials. The date of the most recent search was 14 August 2009.
METHODS
Randomised, double-blind, placebo-controlled trials of sublingual immunotherapy in adults or children. Primary outcome measures were symptom and medication scores. We also collected adverse event data.
METHODS
Two independent authors selected studies and assessed risk of bias. One author extracted data which was rechecked by two other authors. We used the standardised mean difference (SMD) with a random-effects model to combine data.
RESULTS
We included a total of 60 randomised controlled trials in the review. Forty-nine were suitable for pooling in meta-analyses (2333 SLIT, 2256 placebo participants). Overall, we found a significant reduction in symptoms (SMD -0.49; 95% confidence interval (CI) -0.64 to -0.34, P < 0.00001) and medication requirements (SMD -0.32; 95% CI -0.43 to -0.21, P < 0.00001) in participants receiving sublingual immunotherapy compared to placebo. None of the trials included in this review reported severe systemic reactions or anaphylaxis, and none of the systemic reactions reported required the use of adrenaline.
CONCLUSIONS
This updated review reinforces the conclusion of the original 2003 Cochrane Review that sublingual immunotherapy is effective for allergic rhinitis and has been proven to be a safe route of administration.
load more...