鲇脑垂体发生形态学的光镜和激光扫描共聚焦显微观察

OBSERVATIONS ON THE MORPHOLOGICAL DEVELOPMENT OF PITUITARY OF SILURUS ASOTUS WITH LIGHT AND LASER SCANNING CONFOCAL MICROSCOPE

应用光镜和激光扫描共聚焦显微镜对鲇脑垂体发生形态学进行观察:鲇脑垂体由两个不同部位的胚胎细胞形成,原始口腔背壁外胚层分离出来的细胞构成腺垂体的前外侧部(RPD)和中外侧部(PPD),从间脑腹面漏斗体分离出来的细胞构成腺垂体中间部(PI)及神经垂体.3 d龄仔鱼脑垂体的形态业已建成,属前后型.5 d龄仔鱼脑垂体可区分出神经垂体及腺垂体,腺垂体可区分出RPD、PPD、和PI 3个区域,并开始出现毛细血管.此时,PPD内的生长激素(GH)细胞已经分化.11 d龄稚鱼脑垂体中除PPD内GH细胞已分化外,未见其它促激素分泌细胞分化.15 d龄稚鱼脑垂体PPD内的促肾上腺皮质素(ACTH)细胞及催乳激素(PRL)细胞已分化.20 d龄稚鱼脑垂体内各种激素分泌细胞完全分化.11 d龄以前仔鱼脑垂体属前后型,15d龄和20d龄的稚鱼脑垂体内RPD、PPD和PI3部分呈垂直状排列,性成熟鲇脑垂体结构呈背腹型.

The morphological development of the pituitary of Silurus asotus was studied with laser scanning confocal microscope. It is shown that the pituitary of Silurus asotus originated from two embryonic cells of different position; the doral wall of the original cavum oris formed the rostralis pars distalis (RPD) and the proximal pars distali (PPD) and the infundibulum of the ventral part of diencephalons formed the pars intermedia (PI) and the neurohypophysis. In a 3 - day old larva, the pituitary is formed and is of front-back style. In a 5-day old larva, the neurohypophysis and the pituitary gland can be distinguished. Blood capillary began to spread inside the pituitary gland. One can also make out the RPD, the PPD and the PI. At this time, the growth hormone (GH) cells in the PPD have differentiated. Except for the GH cells in the PPD, no other hormone cells were found differentiated. The ACTH and the PRL in the RPD do not differentiate until the larva got 15 - day old. In a 20 - day old larva, all hormone cells in the pituitary had differentiated. The pituitary is of front- back style before 11- day old. For 15 - day and 20 - day old larvas, the arrangement of the RPD, the PPD, the PI appeared vertically . The pituitary in the Silurus asotus of sexual maturity appeared as dorsoventral style.