大鼠创伤性脑损伤后通过酪蛋白酶谱法测定的μ-钙蛋白酶和m-钙蛋白酶活性的pH依赖性。

pH dependency of mu-calpain and m-calpain activity assayed by casein zymography following traumatic brain injury in the rat.

作者信息

Zhao X, Newcomb J K, Posmantur R M, Wang K K, Pike B R, Hayes R L

机构信息

Vivian L. Smith Center for Neurologic Research, University of Texas-Houston Health Science Center, Department of Neurosurgery, 77030, USA.

出版信息

Neurosci Lett. 1998 May 8;247(1):53-7. doi: 10.1016/s0304-3940(98)00219-5.

DOI:10.1016/s0304-3940(98)00219-5

PMID:9637408

Abstract

Studies employing casein zymographic assays analyzed the effects of varying pH (from pH 6.8 to pH 8.0) on changes in mu-calpain and m-calpain activity in naive, sham-injured and injured rat cortex 3 h following unilateral cortical impact injury. Mu-calpain activity following cortical impact injury was enhanced between pH values of 7.2 and 7.8, with pH 7.5 being optimal. m-Calpain activity was readily detected only between pH values of 7.2 and 7.4, with pH 7.3 producing the most prominent proteolytic activity. These observations suggest that strict control of pH is an important consideration in assessments of brain pH activation by casein zymography. Moreover, activation of different calpain isoforms, especially after traumatic brain injury, may be differentially influenced by smaller changes in physiological pH than previously recognized.

摘要

采用酪蛋白酶谱分析的研究，分析了在单侧皮质撞击损伤后3小时，不同pH值（从pH 6.8至pH 8.0）对未受伤、假损伤和受伤大鼠皮质中μ-钙蛋白酶和m-钙蛋白酶活性变化的影响。皮质撞击损伤后，μ-钙蛋白酶活性在pH值7.2至7.8之间增强，pH 7.5为最佳值。仅在pH值7.2至7.4之间能轻易检测到m-钙蛋白酶活性，pH 7.3产生最显著的蛋白水解活性。这些观察结果表明，在通过酪蛋白酶谱评估脑pH激活时，严格控制pH是一个重要的考虑因素。此外，不同钙蛋白酶同工型的激活，尤其是在创伤性脑损伤后，可能比之前认为的更容易受到生理pH较小变化的不同影响。