title: 5-Hydroxytryptamine and rat passive peritoneal anaphylaxis.
abstract: Antigen challenge of rats, sensitized by intraperitoneal injection with rat anti-serum, did not result in a detectable increase in the 5-hydroxytryptamine (5-HT) levels in their peritoneal fluids over the background level induced by sensitisation alone. The maximum amount of extravasation produced by intraperitoneal injection of 5-HT into passively sensitised rats was less than that produced by antigen or histamine, and the doses of 5-HT producing these levels of extravasation produced an produced an increase of 5-HT concentrations in the peritoneal fluids. Therefore, 5-HT is unlikely to make much direct contribution to the extravasation produced during rat passive peritoneal anaphylaxis. However, when given intraperitoneally to rats, 5-HT potentiates the extravasation produced by histamine.
mesh_terms: D000707:Anaphylaxis / Q000276:immunology*; D000818:Animals; D001202:Ascitic Fluid / Q000276:immunology; D004396:Coloring Agents; D004306:Dose-Response Relationship, Immunologic; D006632:Histamine / Q000494:pharmacology; D008297:Male; D008784:Methysergide / Q000494:pharmacology; D010047:Ovalbumin / Q000494:pharmacology; D051381:Rats; D013189:SRS-A; D012701:Serotonin / Q000494:pharmacology*
chemical_list: D004396:Coloring Agents; D013189:SRS-A; D012701:Serotonin; D006632:Histamine; D010047:Ovalbumin; D008784:Methysergide