Metabolic activities of the isolated perfused rat kidney.
Metabolic activities of the isolated perfused rat kidney.
复制标题
离体灌注大鼠肾脏的代谢活动。
作者：
J. Nishiitsutsuji;B. Ross;H. Krebs
1.本文介绍了一种离体大鼠肾脏灌流技术。它主要设计用于研究肾脏代谢，但也适合研究分泌功能的某些方面;这对于最低限度的糖尿来说是正常的。通过肌酐清除率测量的肾小球滤过率低于体内，并随时间缓慢下降。2.从各种前体的葡萄糖异生是快速的，类似于肾皮质切片，在与肝脏相比，灌注器官是更有效的切片。而甘油和丙酮酸的最大产酶速率在肝脏和肾脏中相似，琥珀酸、苹果酸和富马酸的产酶速率是肾脏中的14-20倍，谷氨酸和天冬氨酸的产酶速率约为肾脏中的3倍。3.灌注器官的耗氧量约为皮质切片的两倍，这可能是因为灌注器官中完成了分泌工作，而不是切片。4.乙酰乙酸氧化的速率在灌注器官和切片中大致相同，但由于氧消耗速率较高，乙酰乙酸对呼吸燃料的贡献百分比在灌注器官中较低。结果表明，乙酰乙酸能为细胞的基本需要和生殖过程提供能量，但不能为分泌工作提供能量。5.谷氨酰胺由谷氨酸以高速率形成，而由天冬氨酸以较低速率形成。高比率表明，在大鼠中，肾脏是体内谷氨酰胺的主要来源。
1. A technique for perfusing the isolated rat kidney is described. It is primarily designed for the study of renal metabolism but is also suitable for studying some aspects of the secretory function; this was normal with respect to minimal glucosuria. The glomerular filtration rate as measured by creatinine clearance was lower than in vivo and slowly decreased with time. 2. Gluconeogenesis from a variety of precursors was rapid and similar to that in kidney-cortex slices, in contrast with liver where the perfused organ is more effective than slices. Whereas the maximal rates of gluconeogenesis from glycerol and pyruvate were similar in liver and kidney, the rates from succinate, malate and fumarate were 14-20 times, and those from glutamate and aspartate about three times, as high in the kidney. 3. The oxygen consumption of the perfused organ was about twice that of cortex slices, presumably because of the secretory work done in the perfused organ but not in slices. 4. The rate of acetoacetate oxidation was about the same in the perfused organ and in slices but, because of the higher rate of oxygen consumption, the percentage contribution of acetoacetate to the fuel of respiration was lower in the perfused organ. The results suggest that acetoacetate can supply energy for the basal requirements and for gluconeogenesis but not for the secretory work. 5. Glutamine was formed at a high rate from glutamate and at a lower rate from aspartate. The high rates indicate that, in the rat, the kidney is a major source of body glutamine.