生前电击与死后电击骨骼肌肌小节的长度变化

A study on antmortem and postmortem changes of sarcomere length of skeletal muscle in death from electrocution in rabbits

目的研究生前电击与死后电击的肌小节长度变化,为生前电击与死后电击的鉴别提供新的方法。方法12只兔随机分为对照I组、对照II组、电击死组和死后电击组。每组3只。对照I、II组与死后电击组兔分别从耳缘静脉注射空气30m l处死。对照I组处死后,于死后即刻取其后肢股四头肌;对照II组死后24h于相同部位取材;电击死组兔通220V交流电,通电致兔死后即刻取材;死后电击组于死后即刻通220V交流电4m in后,在相同部位取材。用透射电镜观察骨骼肌肌小节长度变化,对所得结果进行统计学分析。结果生前电击与死后电击骨骼肌肌小节均缩短,与对照组I相比,前者较后者缩短程度更甚(P=0.000);死后电击组与对照I组相比,仅轻微缩短(P=0.000),对照II组相比,缩短较为明显(P=0.000);对照II组较对照I组的肌小节显著伸长(P=0.000)。结论研究骨骼肌肌小节的长度变化有助于鉴别生前电击与死后电击。

Objective To find a morphological method for identification of postmortem or antemortern electrocution by measurement of sarcomere length of skeletal muscle under transmission electron rulerscope. Methods 12 rabbits were randomly divided into four groups, three rabbits in each group： control group Ⅰ, control group Ⅱ, electrocution group, and group electrocuted after death. In control group Ⅰ and Ⅱ, the rabbits were executed by air injection via marginal vein of the ear. Quadriceps femoris of the left hind limb was sampled immediately after death in control group Ⅰ. In control Ⅱ group, the skeletal muscle was collected 24h after death. In electrocution group, rabbits were electrocuted to death by 220 voltage AC. Quadriceps femoris of the left hind limb was sampled immediately after death. The rabbits executed by air embolism were electrocuted by 220 voltage AC for 4rain after death followed by sampling. The length of sarcomere were observed and measured under transmission electron microscope. Data were analyzed statistically. Results The length of the sarcomere was shortened in electrocution group, and group electrocuted after death with more shortening in electrocution group（P = 0.000）as compared with that of control group. The sarcomere increased more in length in control group Ⅱ than in control group Ⅰ （ P = 0.000）. Conclusion Measurement of sarcomere length may helpful for identification of antmortem or postmortem electrocution.