VALINE METABOLISM INVIVO - EFFECTS OF HIGH DIETARY LEVELS OF LEUCINE AND ISOLEUCINE
VALINE METABOLISM INVIVO - EFFECTS OF HIGH DIETARY LEVELS OF LEUCINE AND ISOLEUCINE
复制标题
DOI：
10.1016/0026-0495(84)90012-x
复制
发表时间：
1984-01-01
影响因子：
9.8
通讯作者：
HARPER, AE
中科院分区：
文献类型：
--
作者：
BLOCK, KP;HARPER, AE
The short-term effects of feeding rats high levels of L-Leu or L-Ile on Val metabolism in vivo were investigated. Consumption of a low-protein diet containing an additional 5% of Leu resulted in depression within 1 h of the plasma concentrations of Iso, Val, .alpha.-keto-.beta.-methylvalerate, and .alpha.-ketoisovalerate. Concurrently with these changes in blood branched-chain amino acids and branched-chain ketoacids was a rapid increase (51%) in whole-body L-[1-14C]-Val oxidation. Studies with intragastrically administered Leu solutions indicated that the depressions in blood concentrations of Val occurred over the same time period as the stimulation in Val oxidation. Consumption of a low-protein diet containing an additional 5% of Ile had no significant effect on the plasma concentrations of Leu, Val, and .alpha.-ketoisocaproate. A significant (P < 0.01) depression in the plasma concentration of .alpha.-ketoisovalerate was observed 3 h after the diet containing excess Ile had been consumed. Consumption of excess Ile had no significant effect on the rate of Val oxidation in vivo. Liver and muscle branched-chain aminotransferase and liver branched-chain ketoacid dehydrogenase activities were measured. Consumption of excess Leu had no significant effect on either muscle or liver aminotransferase activities, but was associated with a greater than 2-fold increase in hepatic dehydrogenase activity. Consumption of excess Leu resulted in an increase in the percentage of active dehydrogenase from 43 .+-. 5% to 80 .+-. 4%.
