Neuroanatomical studies on the development of the primary facial taste center in fish

本研究采用一般形态学和抗溴去尿嘧啶（BrdU）免疫组织化学方法，揭示了海鲶和鲤鱼FL结构的发育过程。海鲶鱼：在孵化后第5天（P5d）， FL被发现为纵向柱的前部。在P6d第一次观察到倒钩小叶。P12d时，干小叶出现在其他小叶的外侧。在P26d时，4个倒钩小叶占据了滤泡的前半部分，说明倒钩小叶的相对生长大于滤泡的其他部分，在滤泡的中背缘观察到细胞分裂，并持续到孵化后的25天。在P4-6d时，仅在FL的中背侧缘观察到细胞正向分裂。当小叶分化时，细胞分裂不仅分布在内侧边缘，而且沿整个前部边缘分布，细胞分裂在前部方向更加活跃。FL的前伸是由生发带的前运动引起的。新形成的细胞在各水平上向滤泡细胞中心迁移，而不是向后前方向迁移。鲤鱼：在P8d时，FL在髓质中被发现为成对的块状结构，随后向背侧和中侧发育。p10-12d时，fl开始向内侧融合，在P13-15d完成融合。BrdU实验表明，细胞分裂存在于fl的内侧和背表面。随着时间的推移，生发层被限制在细胞的中背表面，细胞分裂的数量在P14-20d最多，一直持续到P50d。细胞的最后分裂主要发生在尾侧滤膜的背内侧部分，早期细胞向腹侧移动，最后细胞形成滤膜的背侧部分。

This study was undertaken to reveal the developmental process of the structures of FL in the sea catfish and carp using general morphological and Antibromodeoyuridine (BrdU) immunohistochemistry methods.Sea catfish : At 5 days of post hatch(P5d) the FL is found as an anterior portion of the longitudinal column. Barbel lobules were first observed at P6d. At P12d, trunk lobule appeared laterodorsal to the other lobules. At P26d, the four barbel lobules occupied the anterior half of the FL, indicating that the relative growth of the lobules was greater than that of the other part of the FL.Cell divisions were observed in the mediodorsal margin of the FL and continued up to 25 days after hatching. At P4-6d cell divisions were observed only in the mediodorsal margin of the FL anteroposteriorly. When the lobules became distinct, cell divisions were distributed not only in the medial margin but also along the entire border of the anterior portion of the FL.Cell divisions became more active in the anterior direction. The anterior extension of the FL is caused by the anterior movement of the germinal zone. The newly formed cells migrated toward the center of the FL at each level of FL rather than in posteroanterior direction.Carp : At P8d the FL was detected as a paired massive structure in the medulla and hereafter grew up to dorsad and mediad. At p10-12d The FLs began to fuse medially and this fusion was completed at P13-15d. BrdU experiments demonstrated the presence of cell division in the medial and dorsal surface of the FLs. As the day passed, the germinal layr was limited in the mediodorsal surface of the FL.The cell divisions were greatest in number at P14-20d and observed up to P50d. The last cell divisions were mainly found in the dorsomedial portion of the caudal FL.The early cells moved to the ventral portion and the last cells formed the dorsal portion of the FL.