An analysis of positive inotropic effects of nitroglycerin in the canine hearts.
1. Nitroglycerin caused dose-dependent increases in regional myocardial contractile force (MCF) in open-chest dogs, along with dose-dependent decreases in left ventricular end-diastolic (LVEDP) and arterial pressures and an increase in plasma catecholamines level. 2. The increase in MCF could not be completely prevented by propranolol along with a slight decrease in LVEDP and no increase in heart rate, although a nifedipine-produced increase in MCF without a significant decrease in LVEDP disappeared with propranolol despite the same decrease in arterial pressure.
Higuchi
M
M
Department of Pharmacology, School of Medicine, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan.
Sakanashi
M
M
D000818:Animals; D002395:Catecholamines / Q000097:blood; D003327:Coronary Disease / Q000188:drug therapy / Q000503:physiopathology; D003331:Coronary Vessels / Q000187:drug effects; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000378:metabolism; D009543:Nifedipine / Q000494:pharmacology; D005996:Nitroglycerin / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology
D002395:Catecholamines; D011433:Propranolol; D005996:Nitroglycerin; D009543:Nifedipine