Xu Zhuan, Kong Yan, Dong Wan-li, Zhang Zheng-chun, Cao Bi-yin
Department of Neurology, First Affiliated Hospital, Soochow University, Suzhou 215006, China.
Zhonghua Yi Xue Za Zhi. 2011 May 10;91(17):1211-4.
To establish the neocortex-striatum-substantia nigra brain slices of rats and observe the medium spiny neurons of striatum under a visible condition so as to explore their electrophysiological characteristics.
The brain slices containing the neocortex-striatum-substantia nigra were prepared from SD rats of postnatal 7 - 10 days. With infrared differential interference contrast (IR-DIC) microscope and patch clamp amplifier whole-cell recording technique, the medium spiny neurons were located in striatum and their spontaneous electrical activity was recorded in the current clamp mode. By infusing the step current, we observed the variation of membrane potentials.
There were three types of conditions in the 92 medium spiny neurons successfully recorded. Among them, 14 were in persistent down state without action potential firing; 61 displayed persistent down state accompanied with interval temporal depolarizing to the threshold potential with action potential firing; and the remaining 17 showed persistent down state with the interval emergent up state. There was no statistical significance in the difference of mean resting and threshold potentials in three neuronal types (P > 0.05). When the neurons received an infused current, their membrane potentials displayed some delays. The variance of electric potentials showed a tendency of reduction along with the reinforcement of infusing current.
The medium spiny neurons of striatum in parasagittal section brain slices reserve their in vivo electrophysiological characteristics. It establishes rationales for an in-depth study of the role of electrical generation and transmission of nigrostriatal access in the pathogenesis of Parkinson's disease.
制备大鼠新皮质-纹状体-黑质脑片，在可视条件下观察纹状体中型多棘神经元，以探索其电生理特性。
取出生后7 - 10天的SD大鼠制备含新皮质-纹状体-黑质的脑片。运用红外微分干涉相差（IR-DIC）显微镜和膜片钳放大器全细胞记录技术，在纹状体中定位中型多棘神经元，并采用电流钳模式记录其自发放电活动。通过注入阶跃电流，观察膜电位的变化。
成功记录的92个中型多棘神经元有三种状态。其中，14个处于持续下行状态，无动作电位发放；61个呈现持续下行状态，伴有间歇性时间性去极化至阈电位并发放动作电位；其余17个表现为持续下行状态，伴有间歇性出现上行状态。三种神经元类型的平均静息电位和阈电位差异无统计学意义（P > 0.05）。当神经元接受注入电流时，其膜电位出现一定延迟。电位变化呈现随着注入电流增强而减小的趋势。
矢状旁切面脑片中纹状体的中型多棘神经元保留了其在体内的电生理特性。这为深入研究黑质纹状体通路的电产生和传递在帕金森病发病机制中的作用奠定了基础。
