摘要
应用细胞内生物电记录技术，观察毒蕈碱对大鼠星状神经节细胞的影响．毒蕈碱５～１０μｍｏｌ·Ｌ－１可使部分非爆发式发放（ｐｈａｓｉｃ）细胞和部分爆发式发放（ｔｏｎｉｃ）细胞发生膜除极反应．这种除极反应在低钙高镁溶液中或在含河豚毒素（０．１μｍｏｌ·Ｌ－１）的溶液中仍然存在．毒蕈碱引起除极反应时常伴膜电阻的增加．当膜电位增大时，除极反应幅度减小．毒蕈碱引起除极反应的同时，可见细胞钙依赖性后超极化电位减小．此外，当对神经节灌流毒蕈碱时，向非爆发式发放细胞输入去极化电流，常见此类细胞出现爆发式发放．结果表明，毒蕈碱对星状神经节细胞的多种作用可能是其使细胞膜钾电导降低所致．
Intracellular recordings were made from isolated left or right stellate ganglia of Wistar rats. Superfusion of muscarine (5-10 μmol·L -1 ) elicited a slow depolarization in a portion of phasic and tonic cells. The depolarization persisted in low Ca 2+ and high Mg 2+ solution or solutions containing tetrodotoxin (0.1 μmol·L -1 ) was often associated with a small to moderate increase in neuronal input resistance, and the responses were reduced by conditioning hyperpolarization. The amplitude and duration of after-hyperpolarization were consistently reduced during the course of muscarine depolarization. Muscarine caused repetitive spikes during supplied depolarization current pulses in phasic neurones. It was concluded that muscarinic responses might be generated by a reduction in membrane potassium conductance in a po- pulation of stellate ganglion cells.
出处
《中国药理学与毒理学杂志》
CAS
CSCD
北大核心
1996年第1期12-16,共5页
Chinese Journal of Pharmacology and Toxicology
基金
英国心脏研究基金
国家自然科学基金
关键词
毒蕈碱
星状神经节
神经节
钾
去极化
大鼠
muscarine
stellate ganglion
ganglia, sympathetic
K + conductance
