Effects of noncarbohydrate substrates on protein synthesis in hearts from fed and fasted rats.
Effects of noncarbohydrate substrates on protein synthesis in hearts from fed and fasted rats.
复制标题
非碳水化合物底物对进食和禁食大鼠心脏蛋白质合成的影响。
DOI：
10.1016/s0022-2828(84)80608-2
复制
发表时间：
1984
影响因子：
5
通讯作者：
Morgan,HE
中科院分区：
文献类型：
--
作者：
Kochel,PJ;Kira,Y;Gordon,EE;Morgan,HE
An overnight fast reduced RNA content and resulted in lower rates and efficiency of protein synthesis when rat hearts were perfusedin vitroand supplied glucose as oxidizable substrate. Decreased efficiency of synthesis was associated with development of a block in peptide chain initiation in hearts of both fed and fasted rats. Provision of pyruvate increased the rate and efficiency of protein synthesis in fasted but not fed tissue, and partially overcame the initiation block in both groups. A mixture of glucose, pyruvate and insulin increased the efficiency of protein synthesis and decreased ribosomal subunit content to similar values in both groups of hearts. Noncarbohydrate substrates, including pyruvate, lactate, acetoacetate and β-hydroxybutyrate, supported higher rates of protein synthesis than glucose in hearts of fasted, but not fed rats. However, mixtures of glucose and either pyruvate, acetoacetate or β-hydroxybutyrate increased the synthetic rate in fed tissue. Provision of noncarbohydrate substrates increased energy availability, as indicated by higher creatine-P/creatine ratios in both groups of hearts, but the synthetic rate increased as a function of creatine-P/creatine ratio only in the fasted tissue. Octanoate and leucine accelerated protein synthesis and increased energy availability in the fed tissue. The mixtures of glucose and noncarbohydrate substrates or octanoate elevated glucose-6-P content. These studies indicate that an overnight fast decreased the capacity for protein synthesis and modified the regulation of synthesis by noncarbohydrate substrates.
