丙氨酰谷氨酰胺对辐射照射大鼠蛋白质代谢的影响

Effects of alanylglutamine on the protein metabolism of the radiated rats

目的:观察辐射对大鼠全身代谢的影响及丙氨酰谷氨酰胺(AlaGln)对辐射损伤引起的蛋白质损耗的恢复作用。方法:以^(60)Co-γ射线照射大鼠造成全身辐射损伤,饲喂添加丙氨酰谷氨酰胺和放射性氨基酸的营养液,48h后收集脏器和血液样本并进行测定。结果:大鼠接受辐射后全身亮氨酸氧化上升,全身蛋白质合成和分解增加,丙氨酰谷氨酰胺可提高骨骼肌谷氨酰胺浓度,降低亮氨酸氧化。结论:通过给受辐射鼠添加丙氨酰谷氨酰胺可有效降低亮氨酸的氧化,影响重要分支侧链氨基酸(BCAA)的代谢,从而对蛋白质代谢产生积极作用。

Objective: To evaluate effects of alanyglutamine (AlaGln) for the protein metabolism of rats that were injured by a γ-ray radiation. Methods: The rats were injured by radiation emitted from 8Gy ^(60)Co-γ rays and subsequently supplemented with a combination of AlaGln and radioactive amino acids. The rats were euthanased to collect the apparatus and blood for the determination of rehabilitative status from the irradiation. Results: By the irradiation, the oxidized leucine level was increased while total protein quantity in the whole body was reduced. By the supplement with AlaGln, the glutamine concentration in skeletal muscle was escalated while the oxidized leucine level was decreased. Conclusion: Alanylglutamine significantly improved the protein metabolism in irradiated rats by reducing the oxidized leucine level and the branched-side amino acid degradation.