急慢性代谢性酸中毒对红细胞内外pH值的影响  

Effects of acute or chronic metabolic acidosis on intracellular pH of rat erythrocytes

作　　者：王贤东[1] 袁媛[1] 王冬[1] 赫曼[1] 刘若彬[1] 

机构地区：[1]甘肃省人民医院,兰州730030

出　　处：《国际麻醉学与复苏杂志》2009年第5期425-428,共4页International Journal of Anesthesiology and Resuscitation

基　　金：甘肃省科学事业费资助项目（0709TCYA024）

摘　　要：目的观察急性或慢性代谢性酸中毒对大鼠红细胞内pH（pHi）、碳酸酐酶（carbonic and hydrase，CA）和钠．氢交换蛋白Ⅰ（Na^＋-H^＋exchanger Ⅰ，NHEⅠ）活性的影响。方法将24只Wistar大鼠随机分为急性组和慢性组。急性组分为：急性对照组（A组）和急性代谢性酸中毒组（B组）；慢性组分为：慢性对照组（c组）和慢性代谢性酸中毒组（D组）（n=6）。急性组采用静脉输注4mmol·kg^-·h^-1 HCl 4h，慢性组采用0．28mol／LNH4Cl喂饲7d，构建大鼠急性和慢性代谢性酸中毒模型；对照组分别给予等量0．9％生理盐水。分别于急性组0、2、4h，慢性组0、1、3、5、7d抽取鼠尾静脉血0．5ml，肝素抗凝后测定血气分析，根据Wilbur等方法测定大鼠红细胞的CA活性；通过激光共聚焦镜检，应用H^＋荧光探针（BCECF-AM）染色，观察红细胞内pH值变化，通过细胞酸化后细胞内pH值的恢复速率检测各条件下细胞膜上NHEⅠ活性改变。结果急性代谢性酸中毒时红细胞NHEⅠ活性下降（P〈0．05），但pHi和CA无明显变化；慢性代谢性酸中毒早期，红细胞pHi、NHEⅠ和CA活性无明显变化，但随着酸中毒的加重，第5天时红细胞CA和NHEⅠ的活性均明显增高（P〈0．05），红细胞pHi下降1．0±0．05（P〈0．05）。结论急性代谢性酸中毒时，红细胞NHEⅠ活性下降，但红细胞pHi和CA活性并没有发生明显的改变；慢性代谢性酸中毒可显著影响大鼠红细胞pHi、CA和NHEⅠ的活性。Objective To investigate the effects of acute or chronic metabolic acidosis on intracellular pH of rat erythrocytes. Methods Acute metabolic acidosis in Wistar rats was induced by infusion of 4mmol/kg HCl for 4 hours; Chronic metabolic acidosis rats was induced by addition of 0.28 mol/L NH4Cl to drinking water for 7 days. The control groups were given 0.9% NaCl in the same time. At 0, 2and 4h after HCl infusion in acute group, and at 0, 1, 3, 5 and 7 days after NH4Cl administration in chronic group, 0. 5ml blood samples were taken. All blood samples were placed in test tubes with heparin anticoagulant solution. Blood gas was analyzed. Carbonic anhydrase activity in rat erythrocytes was assayed by following the hydration of CO2 according to the method described by Wilbur and Anderson. And after stained by BCECF-AM fluorescent probe, the changes of intracellular pH were observed, and the ability of NHE1 were measured by detected recovery rate of intracellular pH by laser scanning confocal microscopy. Results Acute metabolic acidosis inhibits NHE1 activity （P〈0.05） and no changes in phi and carbonic anhydrase activity of rat erythrocyte were seen. On the contrast, it was showed increasing activity of NHE1 and carbonic anhydrase with decreasing phi in rats erythrocytesin chronic metabolic acidosis over five days （P〈0.05）. Conclusion These results suggest that an acute acid load does not alter phi while chronic metabolic acidosis does reduce pHi of rat erythrocyte.

关 键 词：代谢性酸中毒 碳酸酐酶 钠/氢交换蛋白-Ⅰ 红细胞 红细胞pHi 

分 类 号：R589[医药卫生—内分泌]