title: Histamine receptors in adipose tissue: involvement of cyclic adenosine monophosphate and the H2-receptor in the lipolytic response to histamine in isolated canine fat cells.
abstract: The effects of histamine on lipolysis and associated changes in adenosine 3',5'-monophosphate (cyclic AMP) levels were examined in the isolated canine fat cell. Histamine, like norepinephrine, caused a dose-dependent increase in free fatty acid (FFA) and glycerol levels. The lipolytic response to histamine was preceded by a rise in the levels of cyclic AMP and was greatly potentiated by the addition of theophylline. In isolated canine fat cells, histamine (2 muM) caused a 7-fold increase in FFA levels. This effect was inhibited more than 50% in the presence of insulin (0.4 mmu/ml) or prostaglandin E1 (2.8 muM). In similar experiments, cyclic AMP Levels were increased 11-fold by histamine (2 muM) in the presence of 1 mM theophylline. Burimamide (0.1 mM), a histamine H2-receptor antagonist, reduced the effect of histamine (2 muM) on FFA levels as well as the effect on cyclic AMP levels greater than 95% but did not inhibit the lipolytic response to norepinephrine (2 muM). Propranolol (0.01 mM), a beta adrenergic antagonist, reduced the lipolytic response to norepinephrine by 97% but did not inhibit the effects of histamine on FFA or cyclic AMP levels. Tripelennamine and 1,5-diphenyl-3-dimethylaminopyrrolidine, histamine H1-receptor antagonists, inhibited neither the lipolytic response to histamine nor the effect on cyclic AMP levels. It was concluded that histamine induces lipolysis in canine fat cells by a mechanism involving cyclic AMP and the histamine H2-receptor.
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism / Q000502:physiology*; D004285:Dogs; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology / Q000502:physiology*; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology; D050356:Lipid Metabolism; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology; D011955:Receptors, Drug / Q000187:drug effects; D013806:Theophylline / Q000378:metabolism
chemical_list: D005230:Fatty Acids, Nonesterified; D006634:Histamine H1 Antagonists; D007328:Insulin; D011458:Prostaglandins E; D011955:Receptors, Drug; D006632:Histamine; D011433:Propranolol; D013806:Theophylline; D000242:Cyclic AMP; D009638:Norepinephrine