Hydrogen Sulfide as a New Endogenous Gaseous Transmitter in the Cardiovascular System

Hydrogen sulfide (H2S) is a well-known toxic gas with the smell of rotten eggs. Recent studies have shown that H2S is generated in vivo in human and animal organisms and that it participates in many pathophysiological processes. H2S is produced endogenously in mammalian tissues from L-cysteine metabolism mainly by 3 enzymes: cystathionine β-synthetase (CBS), cystathionine γ-lyase (CSE) and 3-mercaptosulfurtransferase (MST). H2S may not only function as a neuromodulator in the central nervous system but it also relaxes gastrointestinal smooth muscles. More importantly, present evidence shows that H2S exerts regulatory effects on the pathogenesis of various cardiovascular diseases such as hypertension, pulmonary hypertension, shock and myocardial injury. The genomic basis of cystathioninuria in humans is 2 nonsense and 2 sense mutations in CSE. This review reveals that H2S is a new endogenous gaseous transmitter in the cardiovascular system.