Vasomotion: Mechanisms and Physiological Importance

Abstract

Vasomotion, rhythmic oscillations in vascular tone caused by local changes in smooth muscle constriction and dilation, has been observed since the invention of the microscope, but its physiological role and its underlying mechanism remain elusive. Present in many tissues, vasomotion might serve as a protective mechanism under conditions of ischemia. Its generation seems dependent on synchronization of a multitude of individual cellular oscillators. The concept of calcium release and uptake by the smooth muscle calcium stores, synchronized by sarcolemmal ion channels, and sometimes influenced by endothelial factors, may provide further understanding of this little-understood phenomenon.