Effects of 1,25(OH)2D3 on cardiovascular function.

1,25(OH)2D3 enhances myocardial contractility with pharmacological doses from 1 to 20 micrograms within 30-60 min. dp/dt modifications induced by 1,25(OH)2D3 are dose dependent and approach linearity from 1 to 10 micrograms. The inotropic effects are not dependent on extracellular Ca2+ levels; but cellular Ca2+ influx or internal Ca2+ movement may be implied. The effect seems not related to the described 1,25(OH)2D3 receptors which implies protein de novo synthesis. A modulation on other receptor-mediated substances acting on Ca2+ movements seems probable.