OBJECTIVETo study the protective function and pathophysiology of cystathionine gamma-lyase (CSE)/hydrogen sulfide (H(2)S) system in hepatic ischemia-reperfusion injury (HIRI) in rats.

METHODSWistar rats were randomly distributed into sham group (n = 18), ischemia-reperfusion (IR) group (n = 18), IR + NaHS group (n = 18) and IR + DL-propargylglycine (PAG) group (n = 18). The hepatic IR model was established by Pringle's hepatic vascular occlusion. At each of the indicated time points (1, 3 and 6 hours after IR), the serum levels of H(2)S and the hepatic CSE activity were measured. The serum levels of inflammatory factors, including TNF-α, IL-10 were determined by ELISA methods. The expression of apoptotic protein, TNF-α, in liver tissue was tested by Western blot assay, cell apoptosis was examined by TUNEL and the histological changes were examined in each group.

RESULTSThe serum levels of H(2)S and CSE activity were significantly increased in group IR compared with group sham at all indicated time points (P < 0.05). The serum level of inflammatory factors (P < 0.01) and the hepatic expression of TNF-α protein (P < 0.05) were elevated obviously in group IR than that in group sham. Administration of NaHS could reduce the production of inflammatory factors in serum (P < 0.01), inhibit hepatic protein expression of TNF-α (P < 0.05) and attenuate the liver histological scores of IR injury (P < 0.05), whereas PAG aggravated them.

CONCLUSIONThe endogenous CSE/H(2)S system maybe involved in the pathogenesis of hepatic IR injury, which suggests that CSE/H(2)S system can protect liver from IR injury in rats by intervening in inflammatory reaction, attenuating the injury severity and inhibiting expression of apoptotic protein TNF-α.