Protective effects of α-melanocyte stimulating hormone and its analogue on endotoxic shock mice

doi:10.3969/j.issn.1002-1949.2001.04.002

Abstract：Objective To study the protective effects of a melanocytestimulating hormone (α-MSH)and its analogue (NDP-MSH)on endotoxic shock mice.Methods The mice were given an intraperitoneal injection of LPS 50 μg/kg and D-Galactosamine 900 mg/kg to reconstruct the endotoxic shock models.The survival rate of endotoxic shock mice was observed after treated by different doses of ɑ-MSH or NDP-MSH through different ways or at different times.The pathologic changes of important organs from the endotoxic shock mice were inspected by routine tissue slice.Results The lethality of endotoxic shock mice which were not given α-MSH was 100% within 9 h. α-MSH (2.5 mg/kg or 5.0 mg/kg) given through caudal vein,peritoneal or subcutaneous ways could reduce the lethality of endotoxemia shock mice and the intraperitoneal injection was the most effective way.The delayed intial death time and the increased survival rate appeared in endotoxic shock mice treated by ip α-MSH 2.5 mg/kg at different times.The most effective time administrating α-MSH to the mice was 1 h after giving LPS.The survival rate of endotoxic shock mice treated by ip α-MSH 2.5 mg/kg 1 h after giving LPS arrived 33.3% within 72 h,but the protective effect of α-MSH was not enhanced by increasing the frequency of administration.In endotoxic shock mice treated by ip NDP-MSH 2.5 mg/kg,the mean time of intial death was delayed 4 h compared with ɑ-MSH group and the survival rate arrived 44.4% within 72 h. The results of pathologic inspection showed that α-MSH could lighten the blood stasis and the cytonecrosis of livers,spleens or lungs caused by LPS.Conclusion α-MSH or NDP-MSH can ease the pathologic damage of mouse important organs caused by LPS and have distinct protective effect on endotoxic shock mice.