醋酸铅对PC12细胞半胱天冬酶-6、-9活性的影响

Effects of lead acetate on caspase-6 and -9 activities in PC12 cells

目的 了解醋酸铅对PC12细胞半胱天冬酶(caspase)-6、-9活性的影响。方法 PC12细胞分别不同时间(12、24、36、48、60、72 h)暴露于不同浓度的醋酸铅(0、62.5、125.0、250.0、500.0 μmol/L),用比色法检测其caspase-6、-9的活性。结果 PC12细胞暴露于250.0μmol/L醋酸铅24 h可见caspase-6活性升高,48 h达高峰(为对照组的5.75倍,P<0.01),至72 h仍高于对照组(P<0.01)。PC12细胞暴露于250.0 μmol/L醋酸铅12 h,caspase-9活性已升高,36 h达高峰(约为对照组的7.48倍,P<0.01),至60 h已降至与对照组无差别的水平。PC12细胞暴露于不同浓度的醋酸铅48 h(caspase-6)和36 h(easpase-9),可见caspase-6、-9活性具有浓度依赖性的增加。结论 醋酸铅可引起caspase-6、-9活性的升高。

Objective To study the effects of lead acetate on the caspase-6 and -9 activities in PC12 cells. Methods PC12 cells were exposed to 0(control), 62.5, 125.0, 250.0, and 500.0 μmol/L lead acetate for 12, 24, 36, 48, 60, 72 hours, respectively, and then caspase-6 and -9 activities were determined by colorimetric assay. Results When PC12 cells were exposed to 250.0 μmol/L lead acetate for 24 hours, caspase-6 activity increased, and reaching its peak at 48 hours (5.75-fold of control group, P < 0.01) and was still significantly higher than that of control group at 72th hour( P < 0.01). When PC12 cells were exposed to 250.0 μmol/L lead acetate for 12 hours, caspase-9 activity increased, reaching its highest at 36th hour(7.48-fold of control group, P < 0.01), but at 60th hour there was no difference between lead-exposed group and control group. When PC12 cells were exposed to different concentrations of lead acetate for 48 hours(caspase-6) and 36 hours(caspase-9), respectively, caspase-6 and -9 activities enhanced in a concentration-dependent manner. Conclusion Caspase-6 and -9 activities in PC12 cells can be increased by lead acetate.