ET-1对人视网膜色素上皮细胞内游离钙浓度的影响

Endothelin-1 on intracellular free Calcium ion concentration in human retinal pigment epithelial cell

目的观察内皮素(endothelin-1,ET-1)对体外培养视网膜色素上皮(retinal pig-mental epithelium,RPE)细胞内游离钙离子浓度([Ca2+]i)的影响。方法用共聚焦显微镜观察1×10-12～0.1×10-6mol.L-1ET-1作用后fluo-3/AM负载的RPE细胞[Ca2+]i的变化和地塞米松(dexamethasone,DEX)与染料木黄酮对其作用的影响。结果含钙溶剂DMEM液溶解的ET-1,RPE细胞[Ca2+]i随着ET-1浓度的增加,反应敏感(F=8.228,P<0.01)。无钙溶剂D-Hank液溶解的ET-1,RPE细胞[Ca2+]i随着ET-1浓度的增加,反应较差(F=1.843,P>0.05),而DEX和染料木黄酮抑制了1×10-9mol.L-1ET-1诱导的[Ca2+]i的升高(F=9.945,P<0.01;F=17.864,P<0.01)。结论ET-1刺激使[Ca2+]i升高,ET-1使[Ca2+]i升高可能主要来自细胞外Ca2+的内流;DEX和染料木黄酮抑制ET-1的作用。

Objective To observe the effect of endothelin-1（ET-1） on intracellular free Calcium ion concentration（[Ca^2＋]i） in retinal pigment epithelial cell（RPEC） cultured in vitro.Methods The fluo-3 penta-acetoxymethyl（fluo-3/AM） loaded RPEC were treated by 1×10^-12-0.1×10^-6 mol·L^-1 ET-1.The changes of [Ca^2＋]i were observed and the effect of dexamethasone（DEX） and genistein on it were also evaluated using a laser scanning confocal microscope.Results The RPEC had a significant and dose dependent increase in [Ca^2＋]i under exposure to 1×10^-12-0.1×10^-6 mol·L^-1 ET-1 solved by DMEM（F=8.228,P〈0.01）,did not in significant D-Hank solving ET-1（F=1.843,P〉0.05）.DEX and genistein suppressed the [Ca^2＋]i elevation induced by 1×10^-9 mol·L^-1 ET-1 in RPE（F=9.945,P〈0.01, F=17.864,P〈0.01,respectively）.Conclusions ET-1 can stimulate [Ca^2＋]i elevation,which may mainly attribute to the entry of extracellular Calcium ion,and DEX and genistein can suppress the effect of ET-1.