大鼠正中视前核注射血管紧张素Ⅱ对近球小管Na^＋，K^＋-ATPase活性的影响  

Effect of microinjection of angiotensin Ⅱ into median preoptic nucleus on Na^＋,K^＋-ATPase activity of proximal tubule in rat

作　　者：罗蕾[1] 刘爱东[1] 刘红[2] 余德芊[1] 高原[3] 

机构地区：[1]遵义医学院生理学教研室,遵义563003 [2]川北医学院生理学教研室,南充637000 [3]遵义医学院珠海校区机能学教研室,珠海519041

出　　处：《解剖学杂志》2009年第6期781-784,共4页Chinese Journal of Anatomy

基　　金：珠海市科技基金资助项目（PC2003010057）

摘　　要：目的：探讨大鼠正中视前核（MnPO）的血管紧张素Ⅱ（AngⅡ）对肾近球小管Na^＋，K^＋-ATPase活性的作用及其途径。方法：SD大鼠MnPO注射AngⅡ，注射后15、45、60、75、105、145min取肾，分离单根近球小管，测定Na^＋，K^＋-AT—Pase活性；注射后取血测定血清的内源性洋地黄样物质（EDLS）。结果：与MnP0注射人工脑脊液（aCSF）相比，注射AngⅡ后60min，血清EDLS水平达峰值，近球小管Na^＋，K^＋-ATPase活性降到最低值，注射后105min，近球小管Na^＋，K^＋-ATPase的活性和血清EDLS水平分别恢复到对照水平。MnPO注射AngⅡ后145min内的EDLS浓度与其近球小管Na^＋，K^＋-ATPase活性呈显著负相关。结论：AngⅡ作用于MnPO可抑制近球小管的Na^＋，K^＋-ATPase活性；AngⅡ在MnPO是通过AT1受体介导的；AngⅡ在MnPO通过AT1受体介导，远距离抑制近球小管Na^＋，K^＋-ATPase活性的途径，可能与EDLS释放增多有关。Objective： To explore the effect and pathway of activation of angiotensin Ⅱ （Ang Ⅱ ） type 1 receptor （AT1 receptor） in median preoptic nucleus on Na^＋,K^＋-ATPase activity in proximal tubules. Methods： 15, 45, 60, 75, 105 and 145 rain after Ang Ⅱ mieroinjected into median preoptic nucleus （MnPO）, the single proximal tubule of rat kidneys was isolated by means of microdessection to detect Na^＋,K^＋-ATPase activity. The endogenous digitalis-like substance （EDLS） levels in serum were detected by radioimmunoassay （RIA）. Results： Serum EDLS was increased and reached peak at 60 min after injection of Ang Ⅱ. There was a negative linear correlation between EDLS and Na^＋,K^＋-ATPase activity in proximal tubules. Conclusion. These findings suggest that Ang Ⅱ in MnPO inhibits Na^＋,K^＋-ATPase aqtivity in proximal tubules, which should be attributed to its capability of modulation of EDLS release via AT1 receptor.

关 键 词：正中视前核 血管紧张素Ⅱ 近球小管 Na^+ K^+-ATPase内源性洋地黄样物质 大鼠 

分 类 号：R135[医药卫生—劳动卫生] R544.1[医药卫生—公共卫生与预防医学]