The sensitivity of nicotinic synapses in bullfrog sympathetic ganglia to alpha-bungarotoxin and neuronal-bungarotoxin.
The sensitivity of nicotinic synapses in bullfrog sympathetic ganglia to alpha-bungarotoxin and neuronal-bungarotoxin.
复制标题
牛蛙交感神经节烟碱突触对α-银环蛇毒素和神经元银环蛇毒素的敏感性。
DOI：
10.1111/j.1476-5381.1994.tb17077.x
复制
发表时间：
1994
影响因子：
7.3
通讯作者：
Horn,JP
中科院分区：
文献类型：
--
作者：
Shen,WX;Jobling,P;Horn,JP
1.用记录牛蛙椎旁交感神经节第9和第10节细胞外复合节后动作电位的方法，测定了烟碱突触对α-银环蛇毒素（α-Bgt）和神经元-银环蛇毒素（n-Bgt）的敏感性。2.高浓度（10 μ M）的α-Bgt应用长达8小时后，在B或C细胞系统的突触传递没有影响。用胶原酶预处理的神经节也对α-Bgt不敏感。在对分离的缝匠肌制备物的对照实验中，神经诱发的抽搐被30-100 nM α-Bgt完全阻断。3. B和C细胞系统中的烟碱传递被30-300 nM n-Bgt可逆地阻断。阻断在暴露于毒素的25-45分钟内出现，并在40-80分钟的半衰期内完全逆转。这与100 μ M（+）-筒箭毒碱阻断后的洗脱时间没有区别。4.结果表明，神经元烟碱受体介导牛蛙交感神经元的神经节传递的神经元烟碱受体的银环蛇毒素敏感性和银环蛇毒素敏感性之间的密切相似之处，这已被报道为在鸟类和哺乳动物的自主准备。
1. The sensitivity of nicotinic synapses to alpha-bungarotoxin (alpha-Bgt) and neuronal-bungarotoxin (n-Bgt) was measured in the B and C cell systems of bullfrog paravertebral sympathetic ganglia 9 and 10 by recording extracellular compound postganglionic action potentials from the rami communicantes. 2. High concentrations (10 microM) of alpha-Bgt applied for up to 8 h had no effect upon synaptic transmission in either the B or C cell system. Ganglia pretreated with collagenase were also insensitive to alpha-Bgt. In control experiments on isolated sartorius muscle preparations, nerve-evoked twitches were fully blocked by 30-100 nM alpha-Bgt. 3. Nicotinic transmission in the B and C cell systems was reversibly blocked by 30-300 nM n-Bgt. Block appeared within 25-45 min of exposure to toxin and reversed fully with a half-time of 40-80 min. This was indistinguishable from washout times after block by 100 microM (+)-tubocurarine. 4. The results demonstrate close parallels between the bungarotoxin sensitivity of neuronal nicotinic receptors mediating ganglionic transmission in functional subclasses of bullfrog sympathetic neurones and the bungarotoxin sensitivity which has been reported for autonomic in avian and mammalian preparations.