山莨菪碱抑制离体交感神经节的胆碱能突触传递

Inhibitory action of anisodamine on cholinergic transmission of toad sympathetic ganglion in vitro

了解山莨菪碱（Ａｍ）对交感神经节细胞烟碱型乙酰胆碱（Ａｃｈ）受体的作用。用离体蟾蜍椎旁神经节细胞内记录技术观察Ａｎｉ对胆碱能突触传递的影响。Ａｎｉ０．１～１．０ｍｍｏｌ·Ｌ－１灌流１５～２０ｍｉｎ（ｎ＝２８），对电刺激交感节前纤维诱发的顺行动作电位，可有起始段上升速率减慢、超极化后电位增大、去极化后电位减小以及在１．０ｍｍｏｌ·Ｌ－１使５７％的细胞（４／７）顺行动作电位发放率下降或完全取消等作用，其综合抑制有效率在０．１，０．３，１．０ｍｍｏｌ·Ｌ－１分别为２０％，５０％和１００％。另外，Ａｎｉ还可逆地降低外源性Ａｃｈ电位的幅度并缩短时程（ｎ＝３）。结论：高浓度Ａｎｉ对交感神经节细胞的烟碱型Ａｃｈ受体有一定的阻断作用。

To find out whether anisodamine (Ani) acts on nicotinic type of acetylcholine(Ach) receptor in the sympathetic ganglion neurons. Using intracellular recording techniques of the toad paravertebral ganglion neurons in vitro to observe effects of Ani on the cholinergic transmission. Of 28 paravertebral ganglion neurons superfused by Am 0.1～1. 0 mmol·L-1 for 15～20 min, the orthodromic action potential evoked by preganglionic stimulation was reversibly nullified or inhibited only in 4 of 7 cells by Am 1.0 mmol·L-1. However, the riserate of initial component of the orthodromic action potential and the amplitude of after-depolarization were decreased, and/or the amplitude of afterhyper polarization was increased in 20%, 50% and 100% of cells bathed by Am 0.1, 0.3 and 1. 0 mmol·L-1, respectively. The amplitude of exogenous Ach-induced depolarization in 3 cells was decreased by 30% and 80% in average during superfusion of Am at 0. 1 and 1. 0 mmol ·L-1. Am at high concentration exhibits some blocking effect on nicotinic type of Ach receptors of the toad sympathetic ganglion neurons in vtiro.