肝细胞肿胀对肉碱棕榈酰转移酶I的抑制作用。

Inhibition of carnitine palmitoyltransferase I by hepatocyte swelling.

作者信息

Guzmán M, Velasco G, Castro J, Zammit V A

机构信息

Department of Biochemistry and Molecular Biology I, Faculty of Chemistry, Complutense University, Madrid, Spain.

出版信息

FEBS Lett. 1994 May 16;344(2-3):239-41. doi: 10.1016/0014-5793(94)00405-6.

DOI:10.1016/0014-5793(94)00405-6

PMID:7910567

Abstract

Incubation of hepatocytes under conditions known to increase their volume, i.e. with amino acids (glutamine, proline) or in hypo-osmotic medium, decreased carnitine palmitoyl-transferase I (CPT-I) activity. This effect of hepatocyte swelling was antagonized by okadaic acid and dibutyryl-cAMP. Physiological concentrations of glutamate inhibited CPT-I activity in digitonin-permeabilized hepatocytes but not in isolated mitochondria. Results suggest that the amino acid-induced inhibition of CPT-I shares a common mechanism with the amino acid-induced stimulation of acetyl-CoA carboxylase and glycogen synthase [(1993) Eur. J. Biochem. 217, 1083-1089].

摘要

在已知会增加肝细胞体积的条件下培养肝细胞，即使用氨基酸（谷氨酰胺、脯氨酸）或在低渗培养基中培养，会降低肉碱棕榈酰转移酶I（CPT-I）的活性。冈田酸和二丁酰环磷腺苷可拮抗肝细胞肿胀的这种作用。生理浓度的谷氨酸可抑制洋地黄皂苷通透的肝细胞中的CPT-I活性，但对分离的线粒体无此作用。结果表明，氨基酸诱导的CPT-I抑制与氨基酸诱导的乙酰辅酶A羧化酶和糖原合酶的刺激具有共同机制[（1993年）《欧洲生物化学杂志》217卷，第1083 - 1089页]。