甲状腺激素T3对心肌细胞钠钾泵及钙泵功能的影响  

Effects of triiodothyronine on the functions of Na^+-K^+ pump and Ca^(2+)pump in myocytes

作　　者：陈群清[1] 陈燕春[2] 闫玉生[1] 朱平[1] 童健[1] 

机构地区：[1]第一军医大学珠江医院心胸外科,广州510282 [2]海军第421医院,广州510318

出　　处：《中国急救医学》2001年第10期571-573,共3页Chinese Journal of Critical Care Medicine

基　　金：广东省自然科学基金资助课题 (项目编号 9940 84)

摘　　要：目的　观察甲状腺激素T3(三碘甲腺原氨酸 )对鼠缺血再灌注 (I/R)心肌细胞钠钾泵及钙泵功能的影响 ,探讨T3在心肌保护中的作用。方法　将实验大鼠分为甲状腺功能正常 (A组 )和甲状腺功能减退 (甲减 ,B组 )两组 ,每组又分别随机分成对照组、缺血组、单纯灌注液组、T3灌注液组 ;测定左室心肌与体重的比值 ;测定各组心肌细胞Na+ -K+ -ATPase、Ca2 +-ATPase活性。结果　甲减状态大鼠心肌细胞Na+ -K+ -ATPase、Ca2 + -ATPase活性分别下降 10 8%、43 2 % (P <0 0 1)。缺血 30min ,A、B两组的Na+ -K+ -ATPase、Ca2 + -ATPase活性均明显降低 ,并随着复灌进一步下降。然而 ,在复灌 2 0min时 ,T3灌注液组的酶活性较单纯灌注液组显著提高 ,A组Na+ -K+ -ATPase活性 (14 93± 0 87) μmol/(mg·h)比较 (12 17± 0 91)μmol/(mg·h) ,P <0 0 5 ,Ca2 + -ATPase活性 (11 2 0± 1 0 7) μmol/(mg·h)比较 (7 33± 0 5 6 ) μmol/(mg·h) ,P <0 0 1;B组Na+ -K+-ATPase(14 10± 0 5 1) μmol/(mg·h)比较 (10 89± 0 76 ) μmol/(mg·h) ,P <0 0 1,Ca2 + -ATPase活性 (6 89± 0 5 2 ) μmol/(mg·h)比较 (5 2 3± 0 71) μmol/(mg·h) ,P <0 0 5。Objective To observe the effects of triiodothyronine(T3) on the functions of Na +-K + pump and Ca 2+ pump in ischemic reperfusion myocytes,and investigate the regulative effects of T3 on myocardial protection.Methods The rats were devided into group A(with normal thyroid function) and group B(with hypothyroidism),and each group were subdivided into control group,ischemic group,control reperfusion group and T3 reperfusion group.The ratio of left ventricular weight to body weight was written down,and Na +-K +-ATPase?Ca 2+ -ATPase activitivities were determined.Results Na +-K +-ATPase and Ca 2+ -ATPase activities were reduced by 10.8% and 43.2% respectively in rats with thyroidectomy.After 30 minutes of ischemic arrest,the activities declined significantly,and were further declined as the reperfusion proceded.However,the activities in T3 reperfusion group were markedly enhanced,eg.in group A,Na +-K +-ATPase activity was(14.93±0.87) vs (12.17±0.91)μmol/(mg·h), P <0 05,Ca 2+ -ATPase activity was (11.20±1.07) vs (7.33±0.56)μmol/(mg·h), P <0 01;and in group B,Na +-K +-ATPase activivity was (14.10±0.51) vs (10.89±0.76)μmol/(mg·h), P <0 01,Ca 2+ -ATPase activity was (6.89±0.52) vs (5.23±0.71)μmol/(mg·h), P <0 05.Conclusions Hypothyroidism and myocardial ischemic reperfusion could badly damage the functions of Na +-K + pump and Ca 2+ pump.However,T3 may enhance the functions,and partially reverse the damage,as could reduce Ca 2+ overload in ischemic reperfusion myocytes.T3 may be beneficial to myocardial protection.

关 键 词：甲状腺激素 三碘甲腺原氨酸 NA^+-K^+-ATP酶 CA^2+-ATP酶 缺血再灌注损伤 心肌保护 心肌缺血 

分 类 号：R363[医药卫生—病理学]