大鼠内侧膝状体腹侧部神经元形态和电生理特征研究  

Electrophysiological and morphological properties of the ventral neurons in medial geniculate body in rats

作　　者：姚小红[1] 万子兵[1] 隋建峰[1] 熊鹰[1] 

机构地区：[1]第三军医大学基础医学部生理学教研室,重庆400038

出　　处：《第三军医大学学报》2004年第8期697-699,共3页Journal of Third Military Medical University

基　　金：国家自然科学基金资助项目 ( 30 371532 )~~

摘　　要：目的　研究内侧膝状体腹侧部 (ventralmedialgeniculatebody ,MGBv)单个神经元的形态结构和基本电生理特性。方法　采用脑片膜片钳全细胞记录技术 ,观察腹侧部神经元的基本电生理特征和不同膜电位水平时动作电位 ,并结合组化染色观察腹侧部神经元的形态结构。结果　尼氏及Biocytin染色显示MGBv神经元胞体呈卵圆型 ,树突分支呈蓬丛样。经电流钳测得MGBv神经元静息电位 ( -5 4 92± 10 85 )mV ,膜电容 ( 5 3 7± 1 98)pF ,膜电阻 ( 945 67± 5 0 7 80 )MΩ ,时间常数 ( 2 10 9 87± 2 496 0 1) μs。通过注入不同的电流改变膜电位可记录到脉冲式或持续性等多样性的动作电位。在电压钳和电流钳下可记录到自发放电活动。结论　MGBv神经元树突分支较浓密 ,呈蓬丛状 ,神经元动作电位形状呈多样性。在电流钳下记录到的自发性电活动的波形与动作电位相似 。Objective To investigate the electrophysiological and morphological properties of the single ventral neuron in the medial geniculate body (MGBv) in rats. Methods The basic electrophysiological properties and action potentials at different levels of membrane potentials were recorded by whole cell patch clamp technique. Morphological properties of ventral neurons in the medial geniculate body were studied by biocytin staining. Results Nissl and biocytin stainings indicated that MGBv neurons were composed of oval shaped cell bodies, and the dendritic branches were tufted. In current clamp recordings, the resting membrane potential was (-54.92±10.85) mV, the input resistance (945.67±507.80) MΩ, the membrane capacitance (5.37±1.98) pF, and the time constant (2 109 87 ±2 496 01) μs. Action potentials under different current inputs were various. Spontaneous discharge could be recorded by voltage clamp and current clamp. Conclusion MGBv dendritic trees are fairly dense with bushy tufted neurons and variety of action potentials under different current inputs in ventral neurons of the medial geniculate body. Spontaneous activities recorded by current clamp are similar to the action potential, which may be the spontaneous action potential due to the exceeding of membrane potential over liminal value.

关 键 词：全细胞膜片钳 动作电位 自发性电活动 蓬丛样神经元 内侧膝状体 大鼠 

分 类 号：R322.81[医药卫生—人体解剖和组织胚胎学] R338.8[医药卫生—基础医学]