蛙背“膀胱经”皮神经末梢兴奋传递的激发

TRIGGER OF EXCITATORY TRANSMISSION OF SKINNERVE ENDINGS IN “URINARY BLADDER CHANNEL” OF BULLFROG'S BACK

实验在牛蛙离体及在体蛙背“膀胱经”皮－神经标本上，刺激一条皮神经外周端而在另一条皮神经外周端纤维细束上记录诱发动作电位（ＥＡＰ）。结果表明外周神经末梢可进行兴奋传递，两神经间距愈近愈易引出ＥＡＰ，当间距≥５０ｍｍ时，仍有０．９４％的标本可引出ＥＡＰ。条件刺激、提高温度、纳洛酮、Ｐ物质、乙酰胆碱、组织胺等均能不同程度提高ＥＡＰ出现率，以Ｐ物质为最佳，可使两神经间距≥５０ｍｍ的标本ＥＡＰ出现率提高至８．３％，但对横向非循经皮条无明显影响，说明有一定循经性。

The preparations of the skinnerve endings in “Urinary Bladder Channel” of bullfrogs back were used. This work further proved that one nerve could induce evoked action potential(EAP) when another peripheral nerve terminal was stimulated. The nearer a nerve ending is to another, the more EAP can be recorded. When the distance between stimulated and recorded nerve is≥50 mm, a little preparation (0.94%) can induce EAP yet. Conditional stimulation, increasing temperature, naloxone, substance P, ACh and histamine can increase the appearing rate of EAP in different degrees. When the distance between stimulated and recorded nerve is ≥50 mm, substance P raises the appearing rate of EAP to 8.3%. It is inferred that substance P could be the excitatory transmitter between peripheral nerve endings. But all of the preparation of the nonchannel area as a control, in which the distance is ≥50 mm, could not induce the EAP. There is a significant difference in appearing rate of EAP between channel and nonchannel area.