Abstract: Objective To assess the protective effect of exogenous hydrogen sulfide (H2S) against myocardial injury after
skeletal muscle ischemia/reperfusion (IR) in rats and explore the mechanism. Methods Thirty-one Wistar rats were
randomized into normal control (n=8), IR group (n=8, with a 4-h reperfusion following a 4-h ischemia of the bilateral hindlimbs
induced using a tourniquet), NaHS group (n=8, with IR and intraperitoneal injection of 14 μmol/kg NaHS), and
DL-propargylglycine (PPG) group (n=7, with IR and intraperitoneal injection of 50 mg/kg PPG). The plasma levels of CK-MB
and the levels of MPO, TNF-α, MDA, T-SOD, and CuZn-SOD in the plasma and myocardial tissues were measured. The
expression of TNF-α in the myocardium was examined using immunohistochemistry. Results Skeletal muscle IR induced
significantly increased plasma CK-MB level (P<0.05) and the levels of MPO, TNF-α, and MDA in the plasma and myocardium,
and significantly decreased plasma and myocardial levels of T-SOD and CuZn-SOD (P<0.05). NaHS treatment significantly
decreased plasma CK-MB level (P<0.05), reduced plasma and myocardial levels of MPO, TNF-α, and MDA, and increased
plasma and myocardial T-SOD and CuZn-SOD in rats with IR (P<0.05), whereas PPG treatment did not produce any obvious
responses (P>0.05). Immunohistochemistry showed an obviously reduced expression of TNF-α in the myocardium in rats with
NaHS treatment compared with those in IR group. Conclusion H2S treatment can alleviate myocardial injury induced by
skeletal muscle IR in rats by inhibiting the inflammatory cytokines and oxidative stress.