Cl^-通道在溶血磷脂酸引起的血管平滑肌细胞增殖中的作用

Role of Cl^- channels in lysophosphatidic acid induced proliferation of vascular smooth muscle cells

目的探讨Cl-通道在溶血磷脂酸(LPA)引起的血管平滑肌细胞(VSMC)增殖中的作用。方法采用细胞计数和氚标胸腺嘧啶脱氧核苷掺入实验,并结合激光共聚焦显微镜上测定细胞内Ca2+浓度等技术,研究不同Cl-通道阻断剂对LPA促大鼠血管平滑肌细胞增殖的影响。结果Cl-通道阻断剂DIDS(二异硫氰酸二丙乙烯二磺酸,0.01~0.1mmol/L)可浓度依赖式的抑制溶血磷脂酸引起的血管平滑肌细胞增殖,其他Cl-通道阻断剂如5-硝基苯丙氨基苯甲酸(NPPB)、4乙酰氨基4异硫氰酸2,2二磺酸(SITS)、二苯丙氨基2,2二羧酸(DPC)(浓度均为10-7~10-3mol/L)和速尿(浓度均为10-5~10-3mol/L)等均无此作用,且DIDS对电压依赖性钙通道没有直接的影响。结论溶血磷脂酸可以开放DIDS敏感的Cl-通道,且该通道可能在溶血磷脂酸引起的血管平滑肌细胞增殖的调控上起一定的作用。

Objective To examine the role of Cl^- channels in lysophosphatidic acid induced proliferation of vascular smooth muscle cells（VSMC）. Methods Through the cells count and ^3H-TdR incorporation, together with confocal laser scanning microscope the[Ca^2＋],the effect of Cl^- channel blockers on proliferaion of VSMC induced by LPA was studied. Results Cl^- channel blockers 4,4-diisothiocyanatostibene 2,2disulphonicacid（DIDS） inhibited LPA induced increase in cell count and ^3H-TdR incorporation into VSMC,this inhibition was dose dependant. Other Cl^- channel blockers such as 5-nitro-2 （3phenylpropylamino） benzonicacid（NPPB） ,diphenylamine2-2′diccarboxylicacid （DPC）, 4-acetamido-4′-isocyanatostilbene-2,2′-disulpphonate（SITS） and furosemide,however,had no obviouse effects（P〉0.05, for cell count and ^3H-TdR incorporation）, and DIDS had no direct effect on voltage gated calcium channel. Conclusion LPA can open DIDS sensitive Cl^- channel,and this channel may play an importmant role in modulating the proliferation of VSMC induced by LPA.