Anaphylaxis in the guinea-pig isolated heart: selective inhibition by burimamide of the positive inotropic and chronotropic effects of released histamine.
1. Anaphylaxis was induced in the isolated heart of the guinea-pig in the presence of burimamide at concentrations of 4 x 10(-5)M and 2.7 x 10(-4)M.2. Burimamide did not affect the immunological release of histamine; however, it selectively antagonized the positive inotropic and chronotropic effects of released histamine. The antagonism of the positive chronotropic effect was concentration-dependent.3. Neither the negative dromotropic effect nor the decrease in coronary flow rate occurring during anaphylaxis were inhibited by burimamide.4. The results are in agreement with the double histamine receptor theory and suggest that, in the heart of the guinea-pig, H(2)-receptors are involved in the positive inotropic and chronotropic effects of released histamine, and H(1)-receptors in the negative dromotropic effect.
D000707:Anaphylaxis; D000818:Animals; D000941:Antigens; D004562:Electrocardiography; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006636:Histamine Release; D007093:Imidazoles / Q000494:pharmacology; D066298:In Vitro Techniques; D010047:Ovalbumin / Q000494:pharmacology; D011955:Receptors, Drug; D013890:Thiourea / Q000494:pharmacology*; D013997:Time Factors; D014159:Transducers
D000941:Antigens; D006634:Histamine H1 Antagonists; D007093:Imidazoles; D011955:Receptors, Drug; D010047:Ovalbumin; D013890:Thiourea