Balaban R S, Soltoff S P, Storey J M, Mandel L J
Am J Physiol. 1980 Jan;238(1):F50-9. doi: 10.1152/ajprenal.1980.238.1.F50.
An improved cortical tubule suspension from the rabbit kidney is described that contains almost entirely proximal convoluted tubules with little contamination by cellular debris or glomeruli. These tubules appear to be capable of active transepithelial transport, since their tubular lumina are open and ouabain inhibits 70% of the QO2. In previous preparations with closed tubular lumina, ouabain inhibited QO2 only 40% and the base-line QO2 was one-half to one-quarter that of the present preparation. The delivery of oxygen to this tubule suspension was compared to that of slices by three different means: oxygen consumption kinetics, ATP content, and, more directly by spectrophotometric monitoring of the redox state of cytochrome oxidase. Results demonstrate that the cortical slice is evidently oxygen deficient even when the bath PO2 is in excess of 570 mmHg. In contrast, the tubule suspension is shown to be adequately oxygenated even at a bath PO2 of 10 mmHg. This tubule suspension will be highly applicable for the analysis of aerobic metabolism in a functionally intact renal preparation by optical, electrode, and biochemical assay technologies.
本文描述了一种改良的兔肾皮质小管悬液，其几乎完全由近端曲管组成，细胞碎片或肾小球的污染极少。这些小管似乎能够进行活跃的跨上皮转运，因为它们的管腔是开放的，哇巴因可抑制70%的氧耗量（QO2）。在先前管腔封闭的制备物中，哇巴因仅抑制40%的QO2，且基线QO2仅为本制备物的二分之一至四分之一。通过三种不同方法比较了该小管悬液与切片的氧输送情况：氧消耗动力学、三磷酸腺苷（ATP）含量，以及更直接地通过分光光度法监测细胞色素氧化酶的氧化还原状态。结果表明，即使浴液中的氧分压（PO2）超过570 mmHg，皮质切片显然仍存在氧缺乏。相比之下，即使在浴液PO2为10 mmHg时，小管悬液仍显示出充分的氧合。这种小管悬液将非常适用于通过光学、电极和生化检测技术对功能完整的肾脏制剂中的有氧代谢进行分析。
