Ma N, Aoki E, Semba R
Department of Anatomy, Mie University School of Medicine, Japan.
J Histochem Cytochem. 1994 May;42(5):621-6. doi: 10.1177/42.5.7908911.
Biochemical studies have revealed considerable amounts of free amino acids in the kidney. We examined the intrarenal distribution of three amino acids (aspartate, glutamate, and taurine) in the rat kidney with an immunoperoxidase method. In the renal cortex, all three amino acids were concentrated in the renal corpuscles and in the epithelia of the collecting tubules. Immunostaining of the collecting tubules was more intense in the principal cells than in the intercalated cells. The distal convoluted tubules were also immunostained with aspartate- and glutamate- specific antibodies but not with the taurine-specific antibody. In the renal medulla, the immunoreactivity specific for aspartate and for glutamate was similar; it was weak in the thick portion of the loop of Henle and strong in the collecting tubules. Immunoreactivity specific for taurine was restricted to regions within the epithelia of the thin portion of the loop of Henle and the collecting tubules. The significance of the accumulated amino acids as osmoregulatory agents is discussed.
生化研究显示，肾脏中存在大量游离氨基酸。我们采用免疫过氧化物酶法研究了大鼠肾脏中三种氨基酸（天冬氨酸、谷氨酸和牛磺酸）的肾内分布。在肾皮质中，这三种氨基酸均集中于肾小体和集合小管上皮细胞。集合小管主细胞的免疫染色比闰细胞更强。远曲小管也被天冬氨酸和谷氨酸特异性抗体免疫染色，但未被牛磺酸特异性抗体免疫染色。在肾髓质中，天冬氨酸和谷氨酸的免疫反应性相似；在髓袢厚段较弱，在集合小管较强。牛磺酸的免疫反应性仅限于髓袢细段上皮细胞和集合小管内的区域。文中讨论了积累的氨基酸作为渗透调节因子的意义。
