The Hemodynamic Effects of Strontium Chloride in the Intact Dog

Abstract

Summary

The hemodynamic effects of SrCl₂ given intravenously to intact dogs were studied. Sr²⁺had a positive inotropic effect on the heart, manifested by a rise in peak dp/dt, peak velocity of contractile element (V ce) and a fall in left ventricular end diastolic pressure. This inotropic effect was not mediated by beta-adrenergic receptors, and was maximal at a serum [Sr] of 5-7 mM. The inotropic effect of Sr²⁺ was associated with an increase in the duration of contraction, and with little if any change in the time to peak dp/dt, and did not appear to be a simple “Ca²⁺-like” effect. Sr²⁺ also caused a rise in peripheral resistance in dogs with pharmacological blockade of both alpha and beta-adrenergic receptors. These effects appear to be direct actions of the ion on cardiac and arteriolar muscle.