d -筒箭毒碱对青蛙神经肌肉接头处神经递质释放的突触前效应。

Presynaptic effects of d-tubocurarine on neurotransmitter release at the neuromuscular junction of the frog.

Matzner H, Parnas H, Parnas I

Otto Loewi Center for Cellular and Molecular Neurobiology, Hebrew University, Jerusalem, Israel.

J Physiol. 1988 Apr;398:109-21. doi: 10.1113/jphysiol.1988.sp017032.

Presynaptic effects of d-tubocurarine on neurotransmitter release were examined at the frog neuromuscular junction, using intracellular and extracellular recording techniques. 2. d-Tubocurarine in concentrations of 10(-7)-10(-6) M decreased the quantal content (m) measured by the coefficient of variation and failure methods. 3. d-Tubocurarine produced a shift to the right of the curve relating log quantal content to log [Ca2+]o without changing the slope. 4. The duration of twin-impulse facilitation was not affected by 5 x 10(-7) M-d-tubocurarine. Early facilitation was higher in d-tubocurarine. 5. d-Tubocurarine altered the synaptic delay histogram. The peak of the histogram was shifted to longer delays. Prolongation of the minimal delay was seen in most but not all experiments. 6. These results suggest that d-tubocurarine inhibits release of neurotransmitter by affecting a stage in the process of release, which occurs after the entry of Ca2+ ions.

运用细胞内和细胞外记录技术，在青蛙神经肌肉接头处研究了d -筒箭毒碱对神经递质释放的突触前效应。2. 浓度为10(-7)-10(-6) M的d -筒箭毒碱降低了通过变异系数和失败方法测得的量子含量（m）。3. d -筒箭毒碱使将对数量子含量与对数[Ca2+]o相关的曲线向右移动，而斜率不变。4. 5×10(-7) M的d -筒箭毒碱不影响双脉冲易化的持续时间。在d -筒箭毒碱作用下早期易化作用增强。5. d -筒箭毒碱改变了突触延迟直方图。直方图的峰值移向更长的延迟时间。在大多数但并非所有实验中都观察到最小延迟时间延长。6. 这些结果表明，d -筒箭毒碱通过影响Ca2+离子进入后发生的释放过程中的一个阶段来抑制神经递质的释放。

Presynaptic effects of d-tubocurarine on neurotransmitter release at the neuromuscular junction of the frog.