牛磺酸对H-2O_2引起的大鼠血管平滑肌细胞核[Ca~(2+)]及胞浆[Ca~(2+)]变化的影响

目的　毒性剂量H2 O2 可引起细胞坏死或凋亡 ,此过程是否与H2 O2 引起的核 [Ca2 +]([Ca2 +]n)变化有关未见报导。本文研究牛磺酸对H2 O2 引起的血管平滑肌细胞(VSMC) [Ca2 +]n 与胞浆 [Ca2 +]([Ca2 +]c)的变化影响。方法　应用激光共聚焦显微镜对负载Fluo 3的培养大鼠VSMC的 [Ca2 +]n 及 [Ca2 +]c 变化进行研究。结果　在0 5 %H2 O2 作用下 ,[Ca2 +]n 与 [Ca2 +]c 持续升高 ,用抗氧化细胞保护剂 牛磺酸 2 0mmol·L-1预处理细胞 ,可降低H2 O2 引起的 [Ca2 +]n升幅 (P <0 0 5 ) ,但不影响 [Ca2 +]c 升幅 (P >0 0 5 ) ,表明 [Ca2 +]n 变化与 [Ca2 +]c 变化对牛磺酸反应性存在差异。结论　VSMC的核Ca2 +调控与胞浆Ca2 +调控各自具有一定的独立性。牛磺酸对H2 O2 引起的大鼠VSMC核Ca2 +的变化具有保护作用

Effect of taurine on changes of nuclear and cytosolic [Ca~(2 ) ] elicited by H_2O_2 in rat vascular smooth muscle cells

AIM　As one of the reactive oxygen species, toxic dose of H2O2 leads to the necrosis or apoptosis of many kinds of cells. It is nuclear whether these processes are related with the changes of nuclear Ca2+ elicited by H2O2. This study on the effect of taurine on changes of nuclear and cytosolic (Ca2+) elicited by H2O2 in rat vascular smooth muscle cells. METHODS　The techniques of Fluo-3 and laser scanning confocal microscopy were used. RESULTS　Rapid and sustaining rise of nuclear ［Ca2+］ (［Ca2+］n) and cytosolic ［Ca2+］(［Ca2+］c) were found in cultured rat vascular smooth muscle cells upon adding of 0.5% H2O2. Pretreatment of the cells with 20 mmol*L-1 taurine, a regulator of cellular Ca2+ homestasis, significantly decreased the rise amplitude of ［Ca2+］n (P<0.05), but failed to affect that of ［Ca2+］c (P>0.05) elicited by H2O2. It was suggested that the changes of ［Ca2+］n and ［Ca2+］c have different respond to taurine. CONCLUSION　It was concluded that there exist the independent regulating mechanisms of Ca2+ in the nucleus from differences between the nucleus and cytosol Ca2+ in sensitivity to action of H2O2 and taurine.