Pharmacodynamics of BAY K 8644 alone and in combination with dobutamine in the isolated rabbit heart.
The haemodynamic effects of the Ca-agonist BAY K 8644 alone and in combination with the selective beta-I-adrenoceptor agonist dobutamine were studied in the isolated rabbit heart. BAY K 8644 produced a concentration-dependent increase in contraction amplitude and shortening velocity, oxygen consumption and heart rate. In combination with a small fixed concentration of dobutamine (40 nM), Bay K 8644 produced similar alterations. When Bay K 8644 was infused at a fixed concentration (38 nM), dobutamine likewise produced similar increments in contraction amplitude, shortening velocity and heart rate, whereas oxygen consumption was considerably argumented. Both BAY K 8644 and dobutamine showed definite positive inotropic effects in the isolated rabbit heart. Combination of the two drugs did not yield a stronger positive inotropic effect than that seen on single drug administration, and oxygen consumption was even increased.
Sørensen
E V
EV
Institute of Pharmacology, University of Arhus, Denmark.
Pedersen
O L
OL
D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology*; D000818:Animals; D004280:Dobutamine / Q000494:pharmacology*; D004359:Drug Therapy, Combination; D005260:Female; D006321:Heart / Q000187:drug effects*; D006439:Hemodynamics / Q000187:drug effects; D008297:Male; D011817:Rabbits
D004280:Dobutamine; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester