中文摘要：

为探讨褪黑素对内毒素血症山羊肝线粒体功能的影响，将48只山羊随机分为4组，生理盐水组（saline，SL组）、内毒素组（LPS组，1 mg·kg^-1）、褪黑素组（MT组，1 mg·kg^-1）和褪黑素保护组（MT＋LPS组）。各组分别在处理后第3和第6小时各宰杀6只羊，取肝组织，提取肝线粒体和肝线粒体DNA（mtDNA），检测线粒体膜电位（MMP）、ATP酶（ATPase）活性及心磷脂（CL）和肝线粒体DNA氧化产物8-羟基脱氧鸟嘌呤核苷（8-OH-dG）含量。结果显示，与生理盐水组相比，内毒素血症时山羊肝线粒体MMP显著下降，ATPase活性抑制，CL含量显著减少，8-OH-dG水平明显增加；而与内毒素组比，褪黑素保护组山羊肝线粒体MMP明显升高，ATPase活性恢复，CL含量明显增加，8-OH-dG水平显著降低。结果提示，褪黑素能减轻内毒素诱导的山羊肝线粒体损伤，保护肝线粒体功能。

英文摘要：

To investigate the effects of melatonin（MT）on the function of liver mitochondria in goats with endotoxemia, 48 normal goats were divided randomly into four groups： saline（SL） group,LPS group, MT group and MT＋ LPS group. Four groups were treated with saline（SL）, LPS（1mg·kg^-1） , MT（1 mg·kg^-1）and MT＋LPS,respectively. After injection of drugs,livers were collected from 6 killed goats per group at the 3rd hour and 6th hour,respectively. Liver mitochondria and mitochondrial DNA （mtDNA） were extracted for evaluation of mitochondrial membrane potential（MMP）, activity of adenosine triphosphatase（ATPase）, content of Cardiolipin （CL）and level of 8-hydroxy-2＇-deoxyguanine（8-OH-dG）in mtDNA. Results showed that： compared with SL group, MMP of LPS group was obviously declined, activity of ATPase was restrained, content of CL decreased greatly,level of 8-OH-dG increased significantly;but compared with LPS group,MMP of MT＋LPS group was raised obviously, activity of ATPase was significantly recovered, content of CL increased greatly,level of 8-OH-dG decreased apparently. The experimental results indicated that melatonin could reduce liver mitochondrial damage induced by endotoxin, and could protect liver mitochondrial function in goats with endotoxemia.