严重烧伤早期心肌细胞内K^+浓度和细胞膜Na^+-K^+-ATP酶活性的变化  

Changes in intracellular K^+ concentration and ATPase activity of myocardiocytes in early stage of burn injury.

作　　者：李敏[1] 肖家思[1] 阎淑枝[1] 万子兵[1] 

机构地区：[1]第三军医大学生理教研室,重庆630038

出　　处：《中华整形烧伤外科杂志》1996年第3期177-179,共3页

摘　　要：为探讨严重烧伤后早期心肌细胞内 K^+浓度的变化及其机制,采用 K 离子选择微电极技术,测定了大鼠35%TBSAⅢ度烧伤后第1、3、8和24小时心室乳头肌细胞内 K^+活度(并换算成浓度),同时测定了伤后8小时心肌细胞膜 ATP 酶活性。结果表明:①严重烧伤后24小时心肌细胞内 K^+浓度均下降,伤后第1、3、8和24小时分别降为正常值的96.2%±1.3%、85.8%±1.3%、65.9%±1.0%和73.7%±1.1%。伤后8小时达最低值,24小时有所恢复,但仍低于伤后3小时水平;②伤后8小时心肌细胞膜总 AT-Pase,Mg^(2+)-ATPase 和Na^+-K^+-ATPase 活性均降低。提示:烧伤促进 K^+外流,抑制 K^+内流,且烧伤后K^+内流减少与心肌细胞膜 Na^+-K^+-ATPase 活性显著降低有关。In this experiment,intracellular K^+ concentration ([K^+]_i)and ATPase activity of my- ocardiocytes were measured in early stage of burn injury.Comparing with control group,it was found that:①[K^+]_i were decreased after burn in jury;[K^+]_i of 1st、3rd、8th and 24th hours were decreased to 96.2±1.3%、85.8±1.3%、65.9±1.0% and 73.7±1.1% of normal,respectively.②Cardiac sar- colemma total ATPase.Mg^(2+)-ATPase and Na^+-K^+-ATPase activities were all reduced significantly at 8th hour after injury.These results suggest that:burn injury accelerates K^+ efflux current,but inhibits K^+ influx current,and the reduction of Na^+-K^+-ATPase activity is one reason of decrease of [K^+]_i af- ter injury.

关 键 词：烧伤 心肌细胞 钾离子浓度 细胞膜 

分 类 号：R644[医药卫生—外科学]