兔肢体火器伤受海水浸泡后伤道周围骨骼肌Na^+-K^+-ATP酶活性变化

Changes of Na+K+ATPase activities in skeletal muscle of rabbits' limbs with firearm wounds and seawater immersion

目的观察兔肢体火器伤合并海水浸泡时伤道周围骨骼肌组织Ｎａ＋－Ｋ＋－ＡＴＰ酶（Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ）活性变化及其影响因素，为防治继发损伤提供依据。方法以高速钢珠射击兔后肢，伤后将实验兔随机分为海水浸泡和单致伤组。将浸泡组（１４只）兔浸泡于人工配制的海水中３０分钟，于伤前及伤后３，６，１２，２４小时分别切取距伤道壁０．５ｃｍ（Ａ区）、１．５ｃｍ（Ｂ区）、２．５ｃｍ（Ｃ区）处组织，测定Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ和超氧化物歧化酶（ＳＯＤ）活性、ＡＴＰ和丙二醛（ＭＤＡ）含量。单致伤组（１０只）除不浸泡外，处理同海水浸泡组。结果海水浸泡组各区骨骼肌组织Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ活性、ＡＴＰ含量均呈伤后３小时较伤前明显下降（Ｐ＜０．０１），６～１２小时回升，２４小时再次下降的趋势，下降幅度为Ａ区＞Ｂ区＞Ｃ区。ＭＤＡ含量与Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ活性变化呈负相关（ｒ＝－０．７７Ｐ＜０．０１）。单致伤组上述指标变化趋势同海水浸泡组，但变化幅度小。结论肢体火器伤合并海水浸泡时，可加剧伤道周围骨骼肌组织过氧化脂质反应，抑制抗氧化物酶活性，从而导致能量代谢障碍和细胞膜酶活性下降，加剧继发损伤。

Objective To observe the changes and its influencing factors of Na+K+ATPase activities in skeletal muscle of rabbit's limbs with firearm wounds and seawater immersion. Methods The rabbits' thighs were shot and injured with high velocity steel ball and were assigned randomly into the seawater immersion group(SIG) and the simple wound group(SWG).The SIG(14 rabbits) animals were soaked in artificial seawater for 30 min and the skeletal muscle samples were taken from 0.5 cm(zone A),1.5 cm(zone B)and 2.5 cm(zone C)sites apart from the wound tracks before and 3,6,12 and 24 h after the time of trauma.The activities of Na+K+ATPase and superoxide dismutase(SOD) and the contents of adenosine triphosphate(ATP)and malondialdehyde(MDA)of the muscle samples were assayed.The management of SWG(10 rabbits)animals were the same with those of SIG except without seawater immersion. Results Na+K+ATPase activities and ATP contents in all the 3 zones of the skeletal muscle of SIG at 3 h posttrauma were decreased obviously(P<001)and went up from 6 h to 12 h,then decreased again at 24 h as compared with those before trauma.The ranges of decrease were zone A>zone B>zone C.The changes of MDA contents were negatively correlated with that of Na+K+ATPase activities.The tendency of the changes of these biochemical paraments in SWG were the same as those in SIG but with smaller range. Conclusions Lipid peroxidation of the skeletal muscle around the firearm wound track is aggravated when the wound is immersed in seawater.Thereby,the SOD activity is inhibited and would then lead to disturbance of energy metabolism and decrease of activity of membrane enzyme of the skeletal muscle with exacerbation of secondary injury.