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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cyclic adenosine 3', 5'-monophosphate (cAMP) content of isolated unstimulated mast cells and the changes induced by a variety of pharmacologic, metabolic, and physical stimuli were studied. A modified bovine serum albumin density gradient purification method consistently provided mast cell preparations which were 95% or more pure, without apparent damage, and a 73% recovery of the mast cells applied to the gradients. The measured cAMP in unstimulated mast cells was high, a mean of 16 picomoles per million cells. Moderate agitation or contact with glass increased cAMP content about 2-fold. When calcium was omitted from the medium mast cell cAMP was markedly elevated; incremental increases in added calcium ion concentration from 1 muM to 1 mM caused a linear decrease in cAMP content. Theophylline (3 to 20 mM) caused a dose-related increase in mast cell cAMP content, approximately 2-fold at 20 mM theophylline. Epinephrine (0.01 to 1 mM) caused a modest, dose-related increase in cAMP. In the presence of theophylline, epinephrine increased cAMP levels equal to or greater than the sum of the effects of the agents used individually. The increase in cAMP induced by epinephrine was completely inhibited by 100 muM propranolol and partially inhibited by 10 muM propranolol, thus suggesting that a beta adrenergic receptor is involved. Prostaglandin E1 (PGE1) and histamine (in the presence of theophylline) also raised cAMP. Carbamylcholine (1 nM) lowered cAMP 38%; Atropine (0.1 mM) inhibited the decrease in cAMP induced by 1 nM carbamylcholine by 83% indicating that a muscarinic receptor is involved. In these homogeneous single cell suspensions, therefore, cholinergic and beta adrenergic agents have opposing effects on cAMP levels. Diazoxide (10 muM) and adenine (1 muM) caused 37 and 32% decreases in cAMP, respectively. The availability of highly purified mast cells and the identification of agents which either decrease or increase cAMP content allows a direct examination of the role of cAMP in histamine release.
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PMID:Modulation of cyclic AMP in purified rat mast cells. I. Responses to pharmacologic, metabolic, and physical stimuli. 4 63

The intracerebroventricular (ICV) injection of the mast cell degranulator Compound 48/80 (2.5-2.0 micrograms/kg) produced a marked behavioral syndrome in normotensive rats. The behaviors included head and body shakes, paw tremor, excessive grooming, unusual posture and gait, mild diarrhoea, piloerection, extreme agitation and irritability to touch, and a later phase of sedation. The highest doses (15 and 20 micrograms/kg) also produced catalepsy and episodes of "barrel rolling" (continuous rolling of 1-8 turns around the longitudinal axis). These behaviors were observed for approximately 15-30 min although the sedation and catalepsy were maintained for 90-120 min. A second ICV injection of the 10 micrograms/kg dose of Compound 48/80 given 2 hr after an initial injection of this dose, produced a much reduced response and the numbers of head and body shakes, and episodes of paw tremor and grooming were between 20-30% of those produced by the first injection. The reduced effect of the second injection indicates that the behavioral effects of Compound 48/80 may arise from the acute degranulation of mast cells rather than direct effects on neuronal populations or the cerebral vasculature.
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PMID:Acute intracerebroventricular injections of the mast cell degranulator compound 48/80 and behavior in rats. 278 Jul 92

The intracerebroventricular injection of the mast cell degranulator, compound 48/80 (C48/80, 10 micrograms/kg), produced a marked behavioural syndrome in rats which included head and body shakes, paw tremor, excessive grooming, unusual posture and gait, mild diarrhoea, piloerection, extreme agitation and irritability to touch, sedation and catatonia. Fifteen minutes after C48/80, the histamine concentrations were decreased significantly in all brain regions examined, i.e. the cortex, cerebellum, midbrain, medulla oblongata-pons (MO-P) and hypothalamus. The noradrenaline (NA) concentrations were decreased in the cerebellum, hypothalamus and MO-P, whereas the dopamine (DA) content was decreased in the MO-P only. The concentrations of serotonin were not affected. As such, the behaviours following the acute degranulation of brain mast cells by C48/80 may result predominantly from the release of histamine and possibly NA and DA.
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PMID:The effects of intracerebroventricular administration of compound 48/80 on behaviour and regional brain amine concentrations in the rat. 370 80