Effects of Ca++-antagonists on systemic capacitance vessels and venous return curves of dogs--a study with mean circulatory pressure

The effect of FK664, a new cardiovascular drug, on systemic capacitance vessels in anesthetized dogs

To characterize the cardiovascular effect of FK664, a compound developed for the treatment of heart failure, the mean circulatory pressure (MCP), cardiac output and other parameters were measured in open-chest anesthetized dogs. Milrinone, a cardiotonic agent, and nifedipine, a calcium channel blocker were used as reference substances. Nifedipine (10 micrograms/kg), FK664 (0.1 mg/kg) or milrinone (0.1 mg/kg) given intravenously reduced the total peripheral resistance in a similar extent (35-40%). Whereas nifedipine had no effect on MCP, FK664 produced a significant decrease in MCP. Milrinone caused a minimal decrease in MCP, but not significantly. These results indicate that FK664 dilates the systemic capacitance vessels. This action to reduce the pre-load would be beneficial in the treatment of heart failure.