METABOLIC SUBSTRATE UTILIZATION BY RABBIT PROXIMAL TUBULE - AN NADH FLUORESCENCE STUDY
METABOLIC SUBSTRATE UTILIZATION BY RABBIT PROXIMAL TUBULE - AN NADH FLUORESCENCE STUDY
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DOI：
10.1152/ajprenal.1988.254.3.f407
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发表时间：
1988-03-01
影响因子：
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通讯作者：
MANDEL, LJ
中科院分区：
文献类型：
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作者：
BALABAN, RS;MANDEL, LJ
测定了不同短链脂肪酸、羧酸和氨基酸对兔近端小管悬液NADH荧光和耗氧量(QO2)的影响。短链脂肪酸是提高NADH荧光和QO2的最有效底物，其次是羧酸和氨基酸。所有被测底物中，NADH荧光的增加成比例地增加QO2。这表明，这些底物的主要作用是通过增加NAD的还原当量的递送来增加QO2，而不是通过直接刺激ATP水解。测定了几种底物对NADH荧光增强的相对亲和力。短链脂肪酸的亲和力最高(10µm范围)，其次是羧酸(100µm范围)。这些数据表明，肾皮质细胞的代谢率和NADH氧化还原状态对代谢底物的类型非常敏感。
The effects of various short-chain fatty acids, carboxylic acids, and amino acids on NADH fluorescence and oxygen consumption (QO2) of rabbit proximal tubule suspensions were determined. The short-chain fatty acids were the most effective substrates in increasing NADH fluorescence and QO2, followed by the carboxylic acids and amino acids. All of the substrates tested that increased NADH fluorescence proportionally increased QO2. This implies that the primary effect of these substrates was to increase QO2 by increasing the delivery of reducing equivalents to NAD and not by stimulating ATP hydrolysis directly. The relative affinity of several substrates to increase NADH fluorescence was also determined. The short-chain fatty acids had the highest affinity (10 .mu.M range) followed by the carboxylic acids (100 .mu.M range). These data demonstrate that the metabolic rate and NADH redox state of the renal cortical cell is very sensitive to the type of metabolic substrate available.