Effects of platelet activating factor (PAF) and its receptor antagonist BN 52021 on isolated perfused guinea-pig heart.
The cardiac effects of PAF and its antagonist BN 52021 have been investigated on the isolated perfused guinea-pig heart maintained at a constant hydrostatic perfusion pressure of 80 cm water. In this model, PAF (1 x 10(-11) to 1 x 10(-7) moles) induced a dose-dependent coronary vasoconstriction, a decrease in heart rate and a fall in contractile force. BN 52021 (1 x 10(-6) to 2 x 10(-4) M) dose-dependently inhibited the vasospasm induced by PAF (1 x 10(-10) moles). BN 52021 also antagonized the decrease in coronary flow and heart rate, but not that of contractile force induced by a high dose of PAF (1 x 10(-7) moles). This dose of PAF also significantly (p less than 0.001) provoked a marked release of TxB2 but did not alter the generation of 6 Keto PGF1 alpha, PGE2 or LTC4. The PAF-induced increase in TxB2 release was completely abolished by BN 52021.
Viossat
I
I
I.H.B. Research Labs, Les Ulis, France.
Chapelat
M
M
Chabrier
P E
PE
Braquet
P
P
D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects; D004224:Diterpenes; D004305:Dose-Response Relationship, Drug; D046934:Ginkgolides; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects*; D006334:Heart Function Tests; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D007770:L-Lactate Dehydrogenase / Q000097:blood; D007783:Lactones / Q000494:pharmacology*; D009200:Myocardial Contraction / Q000187:drug effects; D010477:Perfusion; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; D010972:Platelet Activating Factor; C045856:ginkgolide B; D007770:L-Lactate Dehydrogenase