乌梢蛇视网膜的显微结构观察

Microstructure of retina in Zoacys dhumnades

采用光镜观察了乌梢蛇(Zoacys dhumnades)视网膜的结构,测量并比较了外核层、内核层与节细胞层的细胞数量,分析了视细胞的分布特征,研究了其视网膜结构与生活习性的关系.结果表明,乌梢蛇视网膜中央区分布着大量的视锥细胞,外核层与节细胞层的细胞数量相当,色素上皮层的细胞有许多突起伸向视杆视锥层内,说明乌梢蛇是一种昼行性蛇类.视网膜盲部接近视部处有椭圆形突起,该突起呈连续分布而形成一圈,突起内可见血窦及丰富的红细胞,该突起可能与锥状突和/或栉膜具有同源关系.

The microstructure of retina in Zoacys dhumnades was observed by light microscopy. The cells in outer nuclear layer, inner nuclear layer, and ganglion cell layer were measured and compared, and the distributing character in visual cell was analyzed. The relationship between the structure of the retina and living habits was also investigated. The results show that a large number of cone cells distributes in the central area of retina,and the number of cell in outer nuclear layer and ganglion cell layer is approximate,and the protuberances of pigment epithelium cells extend to cones and rods layer, which suggest that Zoacys dhumnades is diurnal habitual species. In addition, an oval protuberance in pars caeca retinae near pars optica retinae forms continuous lap, and hemal sinus and abundant erythrocytes exist in the protuberance. The homologous relationship may exist between the protuberance and conus papillaris and/or pectin.