OBJECTIVETo investigate the effect of different doses of ulinastatin (UTI) on the cardiac function and myocardial expression of p38 mitogen-activated protein kinase (p38MAPK) in septic rats.

METHODSForty male SD rats were randomized equally into 5 groups, namely the control group (group A), sham-operated group (group B), sepsis group (group C), low-dose UTI group (group D), and high-dose UTI group (group E). Rat models of sepsis were established by cecal ligation and puncture (CLP), At 24 h after successful modeling, the left ventricle ejection fraction (LVEF) and fractional shortening (LVFS) were evaluated, and the myocardium of the left ventricle was sampled to examine the expression of the expressions of p38MAPK and p-p38MAPK using Western blotting.

RESULTSIn groups A, B, C, D, and E, the LVEF was (77.13∓3.76)%, (76.88∓3.64)%, (56.13∓4.16)%, (55.00∓3.12)%, and (66.50∓3.46)%, and the LVFS was (43.50∓3.70)%, (44.00∓3.38)%, (28.13∓1.81)%, (26.13∓2.70)%, and (38.00∓2.07)%, respectively. Compared with group B at 24 h after CLP, LVEF and LVFS were markedly lowered in the groups C, D and E (P=0.000, 0.000 and 0.002), but showed no significant differences between groups C and D (P=0.541 and 0.166); LVEF and LVFS were significantly lower in group E than in groups C and D (P=0.000 and 0.000). The p-p38/p38 ratio was similar between groups C and D (0.79∓0.12 vs 0.75∓0.12, P=0.682), but both significantly higher than that in group B (0.28∓0.15, P=0.001); the ratio in group E was significantly lower than that in group C (P=0.001), but similar with that in group B (P=0.972).

CONCLUSIONHigh-dose UTI can inhibit p38 phosphorylation, which may be the mechanism for its effect of myocardial protection in septic rat.