Jin J G, Takaki M, Nakayama S
Department of Physiology, Okayama University Medical School, Japan.
Neurosci Lett. 1989 Nov 20;106(1-2):152-6. doi: 10.1016/0304-3940(89)90218-8.
Capsaicin, a neurotoxin which impairs some primary afferent nerve fibers, was locally applied to the mesenteric nerve trunks of adult guinea pigs. The effect of capsaicin was studied on contractile responses of the ileum to mesenteric nerve stimulation (20 Hz). Exposure of the mesenteric nerve to capsaicin (1 microM) irreversibly abolished the contractile response to mesenteric nerve stimulation, without influencing the resting tension and spontaneous motility of the ileum. However, if the mesenteric nerve had been incubated in a Ca-free medium containing EGTA (0.1 mM) or pretreated with Ruthenium red (10 microM), capsaicin only partially inhibited (about 30%), but did not abolish, the contractile response to the mesenteric nerve stimulation, thus indicating protection from desensitization.
辣椒素是一种能损害某些初级传入神经纤维的神经毒素，将其局部应用于成年豚鼠的肠系膜神经干。研究了辣椒素对回肠对肠系膜神经刺激（20赫兹）的收缩反应的影响。将肠系膜神经暴露于辣椒素（1微摩尔）中可不可逆地消除对肠系膜神经刺激的收缩反应，而不影响回肠的静息张力和自发运动。然而，如果肠系膜神经在含有乙二醇双四乙酸（0.1毫摩尔）的无钙培养基中孵育或用钌红（10微摩尔）预处理，辣椒素仅部分抑制（约30%）但不消除对肠系膜神经刺激的收缩反应，从而表明可防止脱敏。
