蝾螈胚胎表皮的自发电活动

本文用常规的细胞内微电极技术观察了东方蝾螈(Cynops orientalis)无神经胚胎表皮细胞的自发电活动,记录了表皮细胞自发活动的振幅和频率,及其出现和消失的变化过程。观察到在胚胎表皮细胞具有传导兴奋能力的阶段,可重复出现自发电活动;在不同胚胎或同一胚胎的不同表皮细胞,自发电活动的振幅和频率都有差别;在自发活动达高潮或稳定期,可兴奋的胚胎表皮细胞之间失去了传导兴奋的能力,待自发活动消失,传导又可恢复;经河豚毒素处理后,表皮细胞自发电活动逐渐消失,用氯化钴处理则影响不大。有关自发电活动的规律和生物学意义正在研究中。     

SPONTANEOUS POTENTIALS OF EMBRYONIC EPITHELIUM IN URODELES (CYNOPS ORIENTALIS)

The spontaneous potentials (SPs) of nerveless embryonic epithelium of Cynops orientaliswere observed by conventional intracellular micro-electrode technique. The amplitude and fre-quency of SPs of epithelial cells and the course of initiation and decline were recorded. TheSPs can occur repeatedly at the stages when the embryonic epithelium is able to conduct exci-tation. The SP is very similar to the evoked propagatable potential, but has shorter duration.The amplitudes and frenquencies of SPs differ in the different embryos and in differentepithelial cells in the same embryo. The excitable epithelial cells of the embryo may lose theirconductivity when the SPs come to a stable phase both in amplitude and frequency. And theconductivity can recover again after the subsiding of SPs. The SPs can be eliminated by tetro-dotoxin (TTX), but they are not affected by the treatment of cobalt chloride.