Zalups R K
Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, Georgia 31207.
Am J Physiol. 1989 Mar;256(3 Pt 2):F387-96. doi: 10.1152/ajprenal.1989.256.3.F387.
This investigation was carried out to determine the effect of potassium on the amplification of the basolateral membrane of principal cells in cortical collecting ducts (CCDs), which normally occurs after a large reduction of renal mass. Rats that underwent a 75% reduction of renal mass and were fed a diet deficient in potassium for 10 days after surgery had a lower concentration of potassium in the blood and excreted less potassium in the urine than either corresponding sham-operated (SO) rats or 75% nephrectomized (NPX) rats fed a normal-potassium diet. In the NPX rats fed the diet deficient in potassium, there was a marked inhibitory effect on the amplification of the basolateral membrane, which normally occurs in principal cells of CCDs after renal mass has been greatly reduced. In fact the surface density of the basolateral membrane, as well as the size of the principal cells in the animals fed the diet deficient in potassium were the same as those of principal cells in the SO rats fed the normal-potassium diet. Thus the present data show that the increase in cell size and the amplification of the basolateral membrane that occurs in principal cells after a 75% reduction of renal mass is inhibited by factors associated with potassium depletion.
本研究旨在确定钾对皮质集合管（CCD）主细胞基底外侧膜扩增的影响，这种扩增通常发生在肾质量大幅减少之后。接受肾质量减少75%手术的大鼠，术后10天喂食低钾饮食，其血液中钾浓度低于相应的假手术（SO）大鼠或喂食正常钾饮食的75%肾切除（NPX）大鼠，且尿钾排泄量也较少。在喂食低钾饮食的NPX大鼠中，对基底外侧膜的扩增有显著抑制作用，而这种扩增在肾质量大幅减少后通常发生在CCD的主细胞中。实际上，喂食低钾饮食的动物的基底外侧膜表面密度以及主细胞大小与喂食正常钾饮食的SO大鼠的主细胞相同。因此，目前的数据表明，肾质量减少75%后主细胞中发生的细胞大小增加和基底外侧膜扩增受到与钾缺乏相关因素的抑制。
