Increased reactivity to histamine in the coronary vascular system of the guinea-pig after endotoxin.
Histamine produced a dose-dependent increase in heart rate, myocardial contractility and coronary flow in the isolated guinea-pig heart using a modified Langendorff procedure. Intraperitoneal treatment of the guinea pigs with E. coli endotoxin, 4 days prior to the experiment, enhanced the positive chronotropic and flow-increasing effect of histamine. The increased response to histamine appeared to be H1-receptor mediated, the positive chronotropic response is attributed to H2-receptors. These results indicate that bacterial endotoxin increases the reactivity of the coronary vascular system of the guinea-pig to histamine.
van Heuven-Nolsen
D
D
Department of Veterinary Pharmacology, University of Utrecht, The Netherlands.
Ten Have
G A
GA
Nijkamp
F P
FP
D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects*; D004731:Endotoxins / Q000633:toxicity*; D006168:Guinea Pigs; D006339:Heart Rate / Q000187:drug effects; D006632:Histamine / Q000494:pharmacology*; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D011968:Receptors, Histamine / Q000502:physiology
D004731:Endotoxins; D011968:Receptors, Histamine; D006632:Histamine