Galicek J, Seow F, Lingard J M
Aust J Exp Biol Med Sci. 1981 Aug;59(4):383-91. doi: 10.1038/icb.1981.32.
Since the few data available concerning the effect of acid/base disturbances on renal amino acid reabsorption were conflicting, and there were sound theoretical reasons for an effect, we have studied the clearance of endogenous amino acids in the rat in vivo under control conditions and after induction of either metabolic acidosis or alkalosis by administration of NH4Cl or NaHCO3, respectively. The effectiveness of treatment was assessed by examination of plasma and urinary levels of HCO3, Cl, Na and K. It was found that the renal clearance of amino acids, measured during acidosis or alkalosis, did not differ from those found under control conditions, the majority of values being less than 1% of the glomerular filtration rate. Thus, the amino acid reabsorptive mechanism appears unaffected by changes in the pH of the glomerular filtrate and/or by changes in tubular hydrogen ion secretion which would accompany such disturbances. These data are thus in agreement with findings during acidosis in man and in both acidosis and alkalosis in the dog. The findings are contrary to earlier reports from in vitro studies in the rat, and suggest the presence of severe functional impairment in the isolated perfused kidneys used in these earlier studies where very large changes in amino acid clearance were obtained.
由于现有的关于酸碱平衡紊乱对肾脏氨基酸重吸收影响的数据相互矛盾，且从理论上讲存在这种影响的合理依据，我们研究了在对照条件下以及分别通过给予氯化铵或碳酸氢钠诱导代谢性酸中毒或碱中毒后，大鼠体内内源性氨基酸的清除情况。通过检测血浆和尿液中碳酸氢根、氯离子、钠离子和钾离子的水平来评估治疗效果。结果发现，在酸中毒或碱中毒期间测得的氨基酸肾脏清除率与对照条件下的结果并无差异，大多数数值低于肾小球滤过率的1%。因此，氨基酸重吸收机制似乎不受肾小球滤液pH值变化和/或伴随此类紊乱的肾小管氢离子分泌变化的影响。这些数据与人类酸中毒以及犬类酸中毒和碱中毒期间的研究结果一致。这些发现与大鼠体外研究的早期报告相反，表明在这些早期研究中使用的离体灌注肾脏存在严重的功能损害，在这些研究中获得了氨基酸清除率的巨大变化。
