人肾皮质对甘氨酸的摄取。

Uptake of glycine by human kidney cortex.

作者信息

Roth K S, Holtzapple P, Genel M, Segal S

出版信息

Metabolism. 1979 Jun;28(6):677-82. doi: 10.1016/0026-0495(79)90022-2.

Abstract

The transport of glycine was investigated in histologically normal adult human kidney cortical slices. Uptake occurs against a gradient and shows concentration dependence. Kinetic analysis reveals two systems for transport of glycine with apparent transport Km values of 0.511 and 34.2 mM. Glycine transport on the high-Km system is competitively inhibited by 50 mML-proline. Transport inhibition on the low-Km system could not be directly evaluated, but on theoretic grounds appears not to be inhibited by L-proline or hydroxyproline. Alpha-aminoisobutyric acid, valine, and thioproline are also shown to inhibit glycine uptake. Low medium sodium or anaerobic incubation depress the uptake of glycine. These observations are consistent with previous reports of glycine transport in rat kidney and support the proposals for the mechanism of familial iminoglycinuria based on in vivo investigations.

摘要

在组织学正常的成人肾皮质切片中研究了甘氨酸的转运。摄取是逆浓度梯度进行的，且表现出浓度依赖性。动力学分析揭示了两个甘氨酸转运系统，其表观转运 Km 值分别为 0.511 和 34.2 mM。高 Km 系统上的甘氨酸转运受到 50 mM L-脯氨酸的竞争性抑制。低 Km 系统上的转运抑制不能直接评估，但从理论上看似乎不受 L-脯氨酸或羟脯氨酸的抑制。α-氨基异丁酸、缬氨酸和硫代脯氨酸也被证明可抑制甘氨酸摄取。低培养基钠或厌氧孵育会降低甘氨酸的摄取。这些观察结果与先前关于大鼠肾脏中甘氨酸转运的报道一致，并支持基于体内研究对家族性亚氨基甘氨酸尿症机制的提议。