美洲大蠊中枢DUM神经元的分离和电压门控Na^＋电流的记录

Isolation of dorsal unpaired median(DUM)neurons from the central nervous system of the cockroach Periplaneta americana and patch-clamp recording of their voltage-gated sodium current

【目的】建立美洲大蠊Periplaneta americana中枢神经系统背侧不成对中间神经元(dorsal unpaired median neurons,DUM neurons)的分离方法和DUM神经元电生理实验模型。【方法】IA型胶原酶法消化美洲大蠊末端腹神经节,机械吹打得到DUM神经元细胞,运用膜片钳技术记录DUM神经元细胞电压门控Na+电流。【结果】分离得到的DUM神经元细胞状态良好,具有DUN神经元典型的梨状形态和表面特征。以膜片钳全细胞方式记录到的Na+电流符合钠通道电流特征。【结论】IA型胶原酶消化得到美洲大蠊DUM神经元细胞的方法可靠,能稳定地记录到Na+电流。本文描述的方法为昆虫神经细胞的电生理机制研究提供一个可用的实验模型。

[ Aim] To grope for the method of isolation of dorsal unpaired median （DUM） neurons from the central nervous system of the cockroach Periplaneta americana and establish an electrophysiological model of DUM neurons. [ Methods ] The terminal abdominal ganglions of P. americana were dissected, DUM neuron cell bodies were obtained after enzymatic treatment with collagenase IA and mechanical dissociation of the median parts of the terminal abdominal ganglion, and the voltage-gated sodium current of DUM neuron cells was recorded by the patch-clamp technique in the whole-cell recording configuration. [ Results ] Isolated DUM neuron cells exhibited typical morphological characteristics of neuronal cells, which are nearly pyriform. Whole-cell sodium currents from DUM neuron cells showed the typical characteristics of sodium currents. [ Conclusion ] DUM neuron ceils can be well obtained by enzymatic treatment, and sodium current can be studied by patch-clamp technique. The procedure described here provides a possible experimental model to study electrical mechanisms of insect nervous svstem.