氯通道参与脑血管平滑肌细胞Ca^(2+)池操纵性Ca^(2+)内流

Chloride Channels Participated in Cerebrovascular Smooth Muscle Cells Ca^( 2+) Store-operated Ca~ 2+ Influx

研究Cl- 通道在牛脑血管平滑肌细胞Ca2 + 池操纵性Ca2 + 内流中的作用。采用培养的脑血管平滑肌细胞 ,在生物荧光双波长影像分析系统用Fura 2 Am荧光探针测定单个细胞内游离Ca2 + 浓度。结果发现 :①Cl- 通道阻断剂DIDS(0 .75 μmol L)能降低内皮素 1(10 - 7mol L)刺激引起的脑血管平滑肌细胞Ca2 + 内流 ,抑制率为 2 9.6 %±3.9% ,随后加入Cl- 通道阻断剂NPPB(10 μmol L)能继续降低平台相 ,抑制率为 4 4 .9%± 8.7% ;交换加药顺序 ,NPPB能降低内皮素 1刺激引起的Ca2 + 内流 ,DIDS能进一步降低Ca2 + 内流。②DIDS(0 .75 μmol L)能降低三磷酸腺苷 (10 μmol L)刺激引起的脑血管平滑肌细胞Ca2 + 内流 ,抑制率为 2 6 .7%± 10 .5 % ,随后加入NPPB(10 μmol L)能继续降低平台相 ,抑制率为 5 4 .3%± 9.6 % ;交换加药顺序 ,NPPB能降低三磷酸腺苷刺激引起的Ca2 + 内流 ,DIDS能进一步降低Ca2 + 内流。③DIDS(0 .75 μmol L)能降低环匹阿尼酸 (10 μmol L)刺激引起的脑血管平滑肌细胞Ca2 + 内流 ,抑制率为 2 6 .5 %± 5 .0 % ,随后加入NPPB(10 μmol L)能继续降低平台相 ,抑制率为 4 6 .1%± 4 .2 % ;交换加药顺序 ,NPPB能降低环匹阿尼酸刺激引起的Ca2 + 内流 ,DIDS能进一步降低Ca2 + 内流。提示对DIDS、NPPB?

Aim To study the effects of chloride channels on cultured bovine cerebrovascular smooth muscle cells (CSMC) Ca 2+ store operated Ca 2+ influx. Method Cell culture and single intracellular free Ca 2+ concentration was measured in Fura 2/Am flueorescence probed by MetaFluor Fluorescence Ratio Imaging System. Results ① Chloride channel inhibitors 4,4' diisothiocyanostibene 2,2' disulphhonate (DIDS,0.75 μmol/L) decreased Ca 2+ influx significantly induced by endothelin 1 (ET 1),adenosine triphosphate (ATP),cyclopiazonic acid (CPA);Subsequent addition 5 nitro 2 (3 phenylpropylamino) benzoate (NPPB,10 μmol/L) further produced the decrease effect. ② NPPB (10 μmol/L) decreased Ca 2+ influx significantly induced by ET 1,ATP,CPA;Subsequent addition DIDS (0.75 μmol/L) also further produced the effect of decreasing. Conclusion Chloride channel inhibitors DIDS, NPPB inhibited Ca 2+ store operated Ca 2+ influx induced by ET 1, ATP, CPA. DIDS,NPPB sensitive chloride channels participated in the signal transduction of Ca 2+ store operated Ca 2+ influx in cerebrovascular smooth muscle cells.