Hydrogen sulphide--a novel mediator of inflammation?

Hydrogen sulphide (H2S) is a naturally occurring gas synthesized from cysteine. It exhibits vasodilator activity (most probably by opening vascular smooth muscle K(ATP) channels), influences leucocyte chemotaxis and promotes vascular smooth muscle cell apoptosis. Increased biosynthesis of H2S has been demonstrated in animal models of septic/endotoxic and haemorrhagic shock, pancreatitis and carrageenan-evoked hindpaw oedema in the rat. In each case, pharmacological inhibition of H2S biosynthesis is anti-inflammatory.