醛糖还原酶抑制剂对糖基化晶状体上皮细胞钠钾ATP酶的刺激作用

Stimulation of glucosylated lens epithelial Na,K-ATPase by an aldose reductase inhibitor.

作者信息

Garner M H, Wang G M, Spector A

机构信息

Department of Ophthalmology, California College of Medicine, University of California, Irvine 92717.

出版信息

Exp Eye Res. 1987 Aug;45(2):339-45. doi: 10.1016/s0014-4835(87)80155-0.

DOI:10.1016/s0014-4835(87)80155-0

PMID:2820775

Abstract

In diabetes, glucosylation of the Na,K-ATPase of the lens epithelium makes the pump inefficient. K+ transport and ATP hydrolysis (at near saturating ATP concentrations) are inhibited and the kinetics of ATP hydrolysis become substrate inhibition type. The AR inhibitor (AL1576, Alcon Laboratories) stimulates K+ transport and ATP hydrolysis by glucosylated bovine lens Na,K-ATPase. This inhibitor has a slight stimulatory effect upon the unmodified enzyme function also. The AR inhibitor is not able to prevent glucosylation of the pump in high-glucose-containing medium.

摘要

在糖尿病中，晶状体上皮细胞的钠钾ATP酶糖基化会使该泵效率低下。钾离子转运和ATP水解（在接近饱和的ATP浓度下）受到抑制，且ATP水解动力学呈底物抑制类型。AR抑制剂（AL1576，爱尔康实验室）可刺激糖基化牛晶状体钠钾ATP酶的钾离子转运和ATP水解。这种抑制剂对未修饰的酶功能也有轻微的刺激作用。在含高葡萄糖的培养基中，AR抑制剂无法阻止该泵的糖基化。