Haemodynamic effects of MS-857, a new cardiotonic agent

• Published in: Japanese Journal of Pharmacology Vol. 46; no. suppl; p. 266
• Main Authors: Banno, Hitoshi, Kawai, Koichi, Maruyama, Masahiko, Kamiya, Joji, Kobari, Takashi
• Format: Journal Article
• Language: English
• Published: The Japanese Pharmacological Society 1988
• ISSN: 0021-5198; 1347-3506
• DOI: 10.1016/S0021-5198(19)57640-5

A new cardiotonic agent, MS-857, has previously been shown to have a vasodilating effect. In the present study the vasodilating property of MS-857 was further evaluated. In a constant-pressure blood perfused system, MS-857 (1-100 nmol) increased blood flow (BF) through the canine femoral (FA) , coronary (CA) , mesenteric (MA) or renal artery (RA) in a dose-dependent manner . Increment of regional BF was in the following order; FA CA MA RA. In case of CA, MS-857 enhanced cardiac contractility in pararell with an increase in BF. In anesthetized dogs, MS-857 (3-30 μg/kg, i.v.) increased cardiac contractility and BF in these regions without causing significant changes in both blood pressure and heart rate . Furthermore , MS- 857 ( 0.1-100 μM) caused a concentration-dependent relaxation of the contractile responses to high-K or PGF_2α in the isolated arteries and veins. In the anesthetized rats, MS-857 markedly lowered the mean circulatory filling pressure. These results suggest that MS-857, in addition to its potent positive inotropic effect , arterial vasodilation and venodilation causes directly, but has a little effect on systemic pressure.