Increased Na+-H+ exchange in brush border vesicles from dogs with renal failure.
Increased Na+-H+ exchange in brush border vesicles from dogs with renal failure.
复制标题
肾衰竭犬刷状缘囊泡中 Na-H 交换增加。
DOI：
10.1152/ajprenal.1982.243.3.f293
复制
发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Hammerman,MR
中科院分区：
文献类型：
--
作者：
Cohn,DE;Hruska,KA;Klahr,S;Hammerman,MR
在慢性肾功能衰竭的残肾模型中，剩余肾单位的近端小管中Na+的绝对重吸收比正常增加。在他的肾脏疾病模型中，近端肾小管重吸收碳酸氢盐的绝对值和近端肾小管H+排泄/肾单位也显示高于正常值。从慢性肾功能衰竭犬残肾刷状缘膜分离的膜囊中的Na+摄取高于从正常犬肾分离的膜囊中的摄取。在本研究中，阿米洛利敏感，电中性Na+-H+交换器被确定在犬肾刷状缘膜囊泡。Na+摄取膜囊泡中的初始H+梯度（囊内pH值小于囊外pH值）的存在下，在膜囊泡中分离的残余肾的狗与慢性肾功能衰竭的膜囊泡从正常的狗的肾脏。阿米洛利消除了这种增加。在慢性肾功能衰竭残肾模型中，Na+和碳酸氢盐重吸收和H+排泄的改变可能可以根据肾刷状缘膜中Na+-H+交换器活性的增加来解释。
In the remnant kidney model of chronic renal failure, absolute reabsorption of Na+ in the proximal tubule of the remaining nephrons is increased over normal. Absolute proximal tubular reabsorption of bicarbonate and proximal tubular H+ excretion per nephron have also been shown to be increased over normal in his model of renal disease. Na+ uptake in membrane vesicles isolated from the brush border membrane of remnant kidneys of dogs with chronic renal failure is increased over uptake in membrane vesicles isolated from kidneys of normal dogs. In the present studies an amiloride-sensitive, electroneutral Na+-H+ exchanger was identified in canine renal brush border membrane vesicles. Na+ uptake in membrane vesicles in the presence of an initial H+ gradient (intravesicular pH less than extravesicular pH) was increased in membrane vesicles isolated from the remnant kidneys of dogs with chronic renal failure over that in membrane vesicles from kidneys of normal dogs. This increase was abolished by amiloride. It is possible that the alterations in Na+ and bicarbonate reabsorption and H+ excretion in the remnant kidney model of chronic renal failure can be explained on the basis of increased activity of the Na+-H+ exchanger in the renal brush border membrane.