铅抑制大鼠背根神经元外向延迟整流钾通道  

Inhibition of voltage-activated outward delayed rectifier potassium channel currents in dorsal root ganglion neurons of rats by lead

作　　者：肖杭[1] 戴晓青[1] 毛霞[1] 石云[1] 程健[1] 姜允申[1] 王心如[1] 

机构地区：[1]南京医科大学公共卫生学院应用毒理研究所,江苏省210029

出　　处：《中华预防医学杂志》2001年第2期108-110,共3页Chinese Journal of Preventive Medicine

摘　　要：目的　观察铅对电压依赖性外向延迟整流钾通道的作用。方法　运用膜片钳技术 ,在急性分离的成年大鼠背根神经节细胞 (DRGs)上进行。结果　记录到DRG神经元外向延迟整流K+ 电流 (IK) ,并观察到铅对IK 的明显影响 ,1 0、2 0、4 0、8 0 μmol/LPb2 + 作用后 ,IK 平均分别减少 (8 6±0 8) %、(38 6± 6 2 ) %、(6 3 0± 5 1) %和 (89 0± 8 8) %。Pb2 + 作用起效甚快 ,在Pb2 + 充分作用后 ,以普通外液冲洗 ,IK 可得到不同程度的恢复。结论　铅在较高浓度可阻断成年大鼠背根神经元电压依赖性外向延迟整流钾通道 ,这种阻断作用是剂量依赖性的。Objective To study the effect of lead on voltage activated outward delayed rectifier potassium channel currents in acute isolated dorsal root ganglion (DRG) neurons of adult rats. Methods Patch clamp technique was employed to record the whole cell of DRG in adult rats. Results In the experiments,delayed rectifier(I K)potassium currents channel was recorded and activation was voltage dependent The threshold concentration of lead (Pb 2+ ) for I K was 1 μmol/L,which reduced potassium current by (8 6±0 8)%,4 μmol/L of Pb 2+ reduced the current by (38 6±6 2)%,and 8 μmol/L of Pb 2+ reduced the current by (63 0±5 1)%. The action of lead was rapid and its effect would be reversed rapidly to various extent by washing. Conclusion Higher outward delayed rectifier potassium channel currents,which could be reversed

关 键 词：铅中毒 脊神经根 脊神经节 钾通道 大鼠 膜片钳术 大鼠 神经毒性 

分 类 号：R338[医药卫生—人体生理学]