酮体对犬亮氨酸和丙氨酸代谢的影响。

The effect of ketone bodies on leucine and alanine metabolism in dogs.

Umpleby A M, Chubb D, Boroujerdi M A, Sonksen P H

Department of Medicine, United Medical School, Guy's Hospital, London.

Clin Sci (Lond). 1988 Jan;74(1):41-8. doi: 10.1042/cs0740041.

Abstract

The effect of an infusion of sodium beta-hydroxybutyrate on leucine and alanine metabolism was investigated in dogs starved for 12 h. To determine whether the metabolic changes produced by this infusion were due to the resultant alkalaemia the effect of an equimolar infusion of sodium bicarbonate was also studied. 2. The sodium beta-hydroxybutyrate infusion reduced alanine concentration as a result of a decrease in alanine production rate and an increase in alanine metabolic clearance rate. The sodium bicarbonate infusion induced a small decrease in alanine concentration which was due to an increased metabolic clearance rate. Alanine production rate showed no change. This demonstrates that the fall in alanine concentration after a sodium beta-hydroxybutyrate infusion is due both to a ketone-specific inhibitory effect on alanine production rate and an increased metabolic clearance rate caused by the alkalaemia. 3. Leucine concentration was increased after the ketone infusion due to a small increase in production rate and there was a small increase in the rate of leucine incorporation into protein. Alkalaemia had no effect on leucine concentration or metabolism.

摘要

在饥饿12小时的犬中研究了输注β-羟基丁酸钠对亮氨酸和丙氨酸代谢的影响。为了确定这种输注所产生的代谢变化是否归因于由此导致的碱血症，还研究了等摩尔输注碳酸氢钠的作用。2. 输注β-羟基丁酸钠后，丙氨酸浓度降低，这是由于丙氨酸生成率降低和丙氨酸代谢清除率增加所致。输注碳酸氢钠导致丙氨酸浓度略有下降，这是由于代谢清除率增加所致。丙氨酸生成率无变化。这表明输注β-羟基丁酸钠后丙氨酸浓度的下降既归因于酮对丙氨酸生成率的特异性抑制作用，也归因于碱血症引起的代谢清除率增加。3. 输注酮后亮氨酸浓度升高，这是由于生成率略有增加，并且亮氨酸掺入蛋白质的速率略有增加。碱血症对亮氨酸浓度或代谢无影响。