二甲基氯化锡对大鼠肾脏氢钾-ATP酶和钠钾-ATP酶活力影响

Effects of dimethyltin chloride on renal H^+K^+-ATPase and Na^+K^+-ATPase activity in rats

目的研究二甲基氯化锡(DMT)对大鼠肾脏氢钾-ATP酶(HKA酶)和钠钾-ATP酶(NKA酶)活力的影响。方法 (1)离体实验:取5只无特定病原体(SPF)级健康雌性SD大鼠肾组织,以0.90%氯化钠溶液制成匀浆液,加入质量浓度为1.0 g/L的DMT配制成终浓度分别为0、1、25、125和625 mg/L的肾匀浆液,采用酶标仪检测HKA酶和NKA酶活力。(2)体内实验:将40只SPF级健康SD大鼠随机分为对照组和染毒组,每组20只,雌雄各半;染毒组大鼠予16.000 mg/kg体质量DMT一次性腹腔注射染毒,对照组大鼠予等体积的0.90%氯化钠溶液,分别于染毒后1和24 h处死;摘取肾脏制备肾匀浆液,采用酶联免疫吸附实验检测肾脏组织中HKA酶和NKA酶活力;采集腹主动脉血,检测血清中钾离子(K^+)、钠离子(Na^+)和氯离子(Cl^-)水平。结果 (1)离体实验:DMT可抑制大鼠肾脏组织中HKA酶活力,随着DMT染毒剂量增加,其对HKA酶活力的抑制作用越明显,呈剂量-效应关系(P<0.01);但DMT对大鼠肾脏组织中NKA酶活力无影响(P>0.05)。(2)体内实验:染毒组大鼠24 h时间点体质量低于该时间点对照组(P<0.01);染毒组大鼠肾脏组织中HKA酶活力低于对照组(P<0.01);大鼠肾脏组织中NKA酶活力以及血清中K^+、Na^+和Cl-水平在染毒处理、染毒时间的主效应及其交互效应上均无统计学意义(P>0.05)。结论 DMT可抑制肾匀浆HKA酶活力,但对肾匀浆NKA酶活力影响不明显。

Objective To study the effects of dimethyltin chloride（ DMT） on the activity of renal H^＋K^＋-ATPase（ HKA）and Na^＋K^＋-ATPase（ NKA） in SD rats. Methods i） In vitro experiment. Five specific pathogen free（ SPF） healthy female SD rats were used. The kidney homogenates made with 0. 90% sodium chloride solution was added with DMT（ mass concentration,1. 0 g/L） to make final concentrations of 0,1,25,125 and 625 mg/L respectively,then the HKA and NKA activities were detected by the enzyme-linked immunosorbent assay（ ELISA）. ii） In vivo experiment. Forty SPF healthy SD rats were divided into control group and exposure group,with 20 rats（ 10 males and 10 females） in each group. The exposure group was given one-time intraperitoneal injection with DMT（ 16. 000 mg / kg body weight）,while the control group was given one-time intraperitoneal injection with same volume of 0. 90% sodium chloride solution. The rats were executed 1 and 24 hours after exposure. The kidney tissue was extracted to make kidney homogenates for determination of HKA and NKA activity by microplate reader. The blood from abdominal aorta was collected to measure the levels of serum K^＋,Na^＋and Cl-. Results i） In vitro experiment. The HKA activity was inhibited by DMT,and the effect of inhibition increased with the increase of DMT exposure dose（ P〈0. 01）,showing a dose-effect relationship. The DMT had no effect on NKA activity（ P〈0. 05）. ii） In vivo experiment. The body weight of rats at 24 hours time point in exposed group was lower than that in control group（ P〉0. 01）. The HKA activity of the kidney tissue in rats in exposed group was lower than that of control group（ P〈0. 01）. The NKA activity in kidney tissue of rats and the level serum K^＋,Na^＋and Cl-did not show statistical difference in main and interactive effects concerning treatment and exposure time（ P〈0. 05）. Conclusion DMT could inhibit the HKA activity in kidney homogenates,but had no obvious effect on NKA activity.