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Updated: Aug 12, 2026

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research
Published on: October 22, 2014
Hydrogen sulfide as a vasodilator
1Department of Pharmacology, Faculty of Medicine, National University of Singapore, Singapore. mbhatia@nus.edu.sg
Abstract:
Gases such as nitric oxide (NO) and carbon monoxide (CO) play important roles both in normal physiology and in disease. The toxic effects of hydrogen sulphide (H2S) on living organisms have been recognized for nearly 300 years. In recent years, however, interest has been directed towards H2S as the third gaseous mediator, which has been shown to exhibit potent vasodilator activity both in vitro and in vivo most probably by opening vascular smooth muscle K(ATP) channels. Of the two enzymes, cystathionine-gamma-lyase (CSE) and cystathionine-beta-synthetase (CBS), which utilize L-cysteine as substrate to form H2S, CSE is believed to be the key enzyme which forms H2S in the cardiovascular system. Recent studies have shown an important role of the vasodilator action of H2S in health and disease.
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