title: In vivo effects of leukotriene B4, C4 and D4. Evidence that changes in blood pressure are mediated by prostaglandins.
abstract: Intra-jugular nanomole injections of leukotrienes B4, C4 and D4 (LTB4, LTC4, LTD4) in anesthetized guinea-pigs have been shown to cause dose-dependent increases of the mean arterial blood pressure. While the responses to LTB4 were monophasic, the responses to LTC4 and LTD4 were characterized by a fast (10-50 sec), medium high, first pressor phase followed by a second, longer lasting (3-9 min), more important pressor phase. Like antigen-antibody reactions, leukotrienes induced cardiac effects such as tachycardia and rhythm disturbances as well as respiratory difficulties, convulsions and sometimes death of the animals. The prostaglandin synthesis inhibitor, indomethacin, reduced the pressor response and the tachyarrhythmic effects of LTB4, C4 and D4. These results raise the possibility that leukotrienes produce their hemodynamic effects in guinea-pigs by stimulating the synthesis and release of biologically active derivatives of arachidonic acid.
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006168:Guinea Pigs; D007213:Indomethacin / Q000494:pharmacology; D007275:Injections, Intravenous; D007601:Jugular Veins; D007975:Leukotriene B4; D008297:Male; D013189:SRS-A / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D001095:Arachidonic Acids; D013189:SRS-A; D007975:Leukotriene B4; D007213:Indomethacin