Effects of diet and of alloxan-diabetes on the activity of branched-chain 2-oxo acid dehydrogenase complex and of activator protein in rat tissues.
Effects of diet and of alloxan-diabetes on the activity of branched-chain 2-oxo acid dehydrogenase complex and of activator protein in rat tissues.
复制标题
饮食和四氧嘧啶糖尿病对大鼠组织中支链2-含氧酸脱氢酶复合物和激活蛋白活性的影响。
DOI：
10.1042/bj2220711
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Philip J. Randle
中科院分区：
文献类型：
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作者：
P. Patston;Joseph Espinal;Philip J. Randle
用标准饮食喂养的正常大鼠的组织中支链2-含氧酸脱氢酶复合物的总活性（活性和非活性形式的总和）为（单位/g湿重）：肝脏，0.82;肾脏，0.77;心脏，0.57;后肢骨骼肌，0.034。9%或0%酪蛋白饮食和48小时饥饿，但不四氧嘧啶糖尿病的肝脏总活性下降。肾脏和心脏的总活性不变。络合物的活性形式的量（以单位/g湿重计）可以通过添加量来确定。和占总量的百分比）为：肝脏，0.45，55%;肾脏，0.55，71%;心脏，0.03，5%;骨骼肌小于0.007，小于20%（低于测定下限）。低蛋白饮食、48 h饥饿和四氧嘧啶糖尿病使肝脏和肾脏中活性形式的复合物浓度降低，但心脏中活性形式的复合物浓度不降低。在心肌四氧嘧啶糖尿病增加了活性复合物的浓度。低蛋白饲料和饥饿48 h可使肝脏和肾脏中激活蛋白（激活磷酸化复合物而不去磷酸化）的浓度降低70-90%。四氧嘧啶糖尿病降低肝脏激活蛋白，但不影响肾脏。有证据表明，在正常饮食喂养的大鼠的组织中，约。70%的全身活性支链复合物在肝脏中，低蛋白饮食引起的活性变化也在肝脏中。
The total activities (sum of active and inactive forms) of branched-chain 2-oxo acid dehydrogenase complex in tissues of normal rats fed on a standard diet were (unit/g wet wt.): liver, 0.82; kidney, 0.77; heart, 0.57; hindlimb skeletal muscles, 0.034. Total activity was decreased in liver by 9%- or 0%-casein diets and by 48 h starvation, but not by alloxan-diabetes. Total activities were unchanged in kidney and heart. The amount of active form of the complex (in unit/g wet wt. and as % of total) in tissues of normal rats fed on standard diet was: liver, 0.45, 55%; kidney, 0.55, 71%; heart, 0.03, 5%; skeletal muscle less than 0.007, less than 20% (below lower limit of assay). The concentration of the active form of the complex was decreased in liver and kidney, but not in heart, by low-protein diets, 48 h starvation and alloxan-diabetes. In heart muscle alloxan-diabetes increased the concentration of active complex. The concentration of activator protein (which activates phosphorylated complex without dephosphorylation) in liver and kidney was decreased by 70-90% by low-protein diets and 48 h starvation. Alloxan-diabetes decreased activator protein in liver, but not in kidney. Evidence is given that in tissues of rats fed on a normal diet approx. 70% of whole-body active branched chain complex is in the liver and that the major change in activity occasioned by low-protein diets is also in the liver.