DECREASED PROTEIN-PHOSPHORYLATION INDUCED BY ANOXIA IN PROXIMAL RENAL TUBULES

被引:30
作者
KOBRYN, CE [1 ]
MANDEL, LJ [1 ]
机构
[1] DUKE UNIV, MED CTR, DEPT CELL BIOL, DIV PHYSIOL & CELLULAR BIOPHYS, DURHAM, NC 27710 USA
来源
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY | 1994年 / 267卷 / 04期
关键词
PROTEIN KINASES; PROTEIN PHOSPHATASES; ACUTE RENAL FAILURE; RENAL ISCHEMIA;
D O I
10.1152/ajpcell.1994.267.4.C1073
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Anoxia-induced depletion of cellular ATP may affect the degree of protein phosphorylation due to kinase inhibition. In this study, protein phosphorylation was measured in rabbit kidney proximal tubules under normoxic or anoxic conditions in a medium containing P-32. During the first 20 min of normoxia, phosphate incorporation was linear, averaging 17 +/- 5 pmol mg protein(-1).min(-1) and was 70% inhibited by the protein kinase C inhibitor chelerythrine chloride. Phosphorylation measurements initiated simultaneously with anoxic conditions (95% N-2-5% CO2) significantly reduced the initial rate to 58% of control, saturating after 15 min, and reaching 28 +/- 5% of the normoxic value after 60 min of incubation. The phosphatase inhibitor calyculin A did not affect the initial rate of phosphate incorporation by anoxic tubules but increased phosphate incorporation at 60 min to 43 +/- 4% of normoxia. Addition of P-32 after 15 min of anoxia abolished phosphate incorporation, demonstrating that kinase activity was completely inhibited. Cellular phosphate uptake was measured and found not to be rate limiting for phosphorylation. Chelerythrine chloride increased lactate dehydrogenase (LDH) release during normoxia, and calyculin A decreased anoxia-induced LDH release, suggesting that protein phosphorylation events may control plasma membrane permeability.
引用
收藏
页码:C1073 / C1079
页数:7
相关论文
共 41 条