The actions of leukotrienes C4 and D4 on guinea-pig isolated hearts.
1 Infusions of leukotrienes C4 (LTC4) and LTD4 (5 min; 4 X 10-10-2 X 10-8 M) produced dose-dependent decreases in coronary flow in Langendorff preparations of guinea-pig isolated heats. 2 LTC 4 was more active than LTD4 and produced greater reduction in coronary flow 3 LTC4 and LTD4 also caused reduction in contractility in perfused hearts but not in isolated atria or driven ventricular strips. 4 There was a greater reduction in contractility to LTD4 compared with LTC4 at doses which produced approximately 50% reduction in coronary flow. 5 Indomethacin (1.4 X 10-5 M) inhibited the effects of LTC4 but only reduced the initial LTD4- induced effects. 6 The effects of FPL 55712 (3.8 X 10-6 M) were similar to those of indomethacin. 7 LTC4 and LTD4 may therefore contribute to the abnormalities of cardiac function that occur in immediate hypersensitivity reactions, particularly reduction in coronary flow.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects; D004347:Drug Interactions; D004558:Electric Stimulation; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects* / Q000502:physiology; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D013189:SRS-A / Q000494:pharmacology*
D013189:SRS-A; D007545:Isoproterenol; D000109:Acetylcholine