Hypoxic vasorelaxation: Ca2+-dependent and Ca2+-independent mechanisms
Related Experiment Video
Updated: Aug 23, 2026

Isolation of Intrapulmonary Artery and Smooth Muscle Cells to Investigate Vascular Responses
Published on: June 8, 2022
George D Thorne1, Yukisato Ishida, Richard J Paul
1Department of Molecular and Cellular Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
Abstract:
The mechanisms of oxygen sensing in vascular smooth muscle have been studied extensively in a variety of tissue types and the results of these studies indicate that the mechanism of hypoxia-induced vasodilation probably involves several mechanisms that combined to assure the appropriate response. After a short discussion of the regulatory mechanisms for smooth muscle contractility, we present the evidence indicating that hypoxic vasorelaxation involves both Ca2+-dependent and Ca2+-independent mechanisms. More recent experiments using proteomic approaches in organ cultures of porcine coronary artery reveal important changes evoked by hypoxia in both Ca2+-dependent and Ca2+-independent pathways.
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