Benzodiazepine Ro 5-4864 increases coronary flow.
Ro 5-4864 (chlorodiazepam) increased coronary flow in isolated retrograde perfused Langendorff rat heart preparations without affecting heart rate and left ventricular contractility (dP/dt). On the other hand Ro 5-4023 (clonazepam) produced very little effect. PK 11195 which has been shown to inhibit the binding of Ro 5-4864 to cardiac muscle did not antagonize this vasodilatory effect of Ro 5-4864 but increased coronary flow by itself. The data indicate a specific vasodilatory effect of certain benzodiazepines. The mechanism of action remains unknown.
Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, OH 45267-0575.
I L
IL
Grupp
J F
JF
French
M A
MA
Matlib
D000818:Animals; D001570:Benzodiazepinones / Q000494:pharmacology*; D002998:Clonazepam / Q000494:pharmacology; D003292:Convulsants / Q000494:pharmacology*; D003326:Coronary Circulation / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D007546:Isoquinolines / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains
D001570:Benzodiazepinones; D003292:Convulsants; D007546:Isoquinolines; C028513:4'-chlorodiazepam; D002998:Clonazepam; C037850:PK 11195