糖皮质激素快速抑制气道平滑肌游离钙升高与磷脂酶C活性的关系  

Rapid inhibitory effect of glucocorticoids on peak of [Ca^(2+)]i and PLC in airway smooth muscle

作　　者：孙海文[1] 刘磊[2] 李鸣皋[1] 蒋春雷[2] 

机构地区：[1]海军总医院航空潜水医学中心,北京100048 [2]第二军医大学航海医学教研室应激研究实验室,上海200433

出　　处：《中国应用生理学杂志》2010年第4期440-443,共4页Chinese Journal of Applied Physiology

基　　金：军队杰出青年基金资助课题(06J010)

摘　　要：目的:本实验通过对平滑肌细胞行GCs快速预处理,拟证实糖皮质激素对平滑肌细胞内[Ca2+]i浓度升高有快速抑制作用,并初步探讨该现象的可能分子机制。方法:原代培养的大鼠平滑肌细胞,应用Fura-2/AM显微荧光检测技术,检测肌细胞内[Ca2+]i在受到激动剂刺激后的浓度变化;比较不同浓度地塞米松预处理后10min与对照组之间游离钙上升情况的区别。用Western blot方法,分析气道平滑肌细胞内抑制型磷脂酶C(phospho-PLCβ-ser1105)含量的变化。设立RU486及CHX对照组,排除基因组作用在该反应中的影响。结果:GCs温浴10min,能够明显降低乙酰胆碱引起的ASMCs细胞内[Ca2+]i峰值。并能够明显上调ASMCs内抑制型PLC含量。这些反应不受RU486和CHX影响。结论:GCs能够通过非基因组作用快速抑制刺激物引起的气道平滑肌的收缩反应,这一效应的实现可能是通过抑制PLC分子活性,使其下游的[Ca2+]i浓度降低实现的。Objective：In this study,we pretreated the mice ASMCs by dexemisone （Dex） within 10 min,to test the peak of [Ca2＋]i and phospho-PLCβ （ser1105） in the cells by treated with Ach. Methods： The peak of [Ca2＋]i was measured by Fura-2/AM methods and the phospho-PLCβ-ser1105 was by Western blot,and compared with dexemisone pretreated groups. Glucocorticoid receptor antagonist RU486 and the protein synthesis inhibitor cycloheximide groups were setted in our study. Results： Glucocorticoids （GCs） significantly decreased the resting values and peak of [Ca2＋]i elevation and elevated the intracellular levels of phospho-PLCβ （ser1105） in 10 min. Neither the RU486 nor cycloheximide could alter the inhibitory effects of glucocorticoids stated above. Conclusion： Our results demonstrate that glucocorticoids exert rapid inhibitory effects. The series of signal changes in this process that restrain the peak of [Ca2＋]i may be responsible for the rapid nongenomic inhibitory effects of GCs by reducing the activity of PLC.

关 键 词：糖皮质激素 气道平滑肌 非基因组机制 胞内游离钙离子 磷脂酶C 

分 类 号：R313-3[医药卫生—基础医学]