Ca2+ Regulation Not Associated with Phosphorylation of Myosin Light Chain in Aortic Intima Smooth Muscle

Abstract

Intimal myosin B considerably retained the Ca²⁺ in the presence of chlor promazine which inhibited the phosphorylation of myosin light chain. This result suggests that the phosphorylation and dephosphorylation of the 20,000-dalton light chain of myosin are not the sole regulatory mechanism in smooth muscle.