成年大鼠感觉神经元在无血清和外源性神经生长因子培养基中培养时的河豚毒素敏感性动作电位和兴奋性

TTX-sensitive action potentials and excitability of adult rat sensory neurons cultured in serum- and exogenous nerve growth factor-free medium.

作者信息

Aguayo L G, Weight F F, White G

机构信息

Section of Electrophysiology, National Institute on Alcohol Abuse and Alcoholism, Rockville, MD 20852.

出版信息

Neurosci Lett. 1991 Jan 2;121(1-2):88-92. doi: 10.1016/0304-3940(91)90656-e.

DOI:10.1016/0304-3940(91)90656-e

PMID:2020393

Abstract

The excitability of adult rat dorsal root ganglion (DRG) neurons cultured in the absence of serum and exogenously added nerve growth factor (NGF) was studied. Current-clamp recordings revealed the presence of tetrodotoxin (TTX)-sensitive action potentials. Voltage-clamp recordings demonstrated the presence of both inward and outward currents. The inward Na+ current had a maximal amplitude near -10 mV and was completely blocked by TTX. A sustained Ca2+ inward current and a slowly activating outward K+ current were also observed. TTX-sensitive and TTX-resistant action potentials have been observed in previous studies in DRG neurons cultured in the presence of serum. By contrast, in the study reported here, only TTX-sensitive action potentials and Na+ currents were found in the neurons cultured in the absence of serum and nerve growth factor.

摘要

研究了在无血清且未外源性添加神经生长因子（NGF）的条件下培养的成年大鼠背根神经节（DRG）神经元的兴奋性。电流钳记录显示存在对河豚毒素（TTX）敏感的动作电位。电压钳记录表明存在内向电流和外向电流。内向Na⁺电流在-10 mV附近具有最大幅度，并且被TTX完全阻断。还观察到持续的Ca²⁺内向电流和缓慢激活的外向K⁺电流。在先前关于在有血清存在的条件下培养的DRG神经元的研究中观察到了对TTX敏感和对TTX耐药的动作电位。相比之下，在本报告的研究中，在无血清和神经生长因子培养的神经元中仅发现了对TTX敏感的动作电位和Na⁺电流。