乌龟脑垂体显微及其腺垂体超微结构的研究

STUDIES ON THE MICRO-STRUCTURE OF PITUITARY GLAND AND ULTRASTRUCTURE OF ADENOHYPOPHSIS IN CHINEMYS REEVESII

乌龟脑垂体由柄形神经垂体和椭圆形腺垂体两部分组成,神经垂体位于腺垂体后部上方呈背腹型排列。神经垂体中神经叶不发达,腺垂体分为远侧部和中间部,特殊空泡结构成为垂体门脉系统的特征。远侧部细胞分为嗜酸性细胞、嗜碱性细胞和嫌色细胞3种。通过透射电镜观察,腺垂体远侧部主要有5种分泌激素细胞:即生长激素(GH)分泌细胞、催乳激素(PRL)分泌细胞、促甲状腺激素(TSH)分泌细胞、促肾上腺皮质激素(ACTH)分泌细胞、促性腺激素(GTH)分泌细胞和非分泌类型滤泡-星形细胞(FS)。生长激素分泌细胞核大、分泌颗粒少的特征成为乌龟与其他动物最大的区别,可能与乌龟具有生长慢、寿命长的生物学特性有关。

Chinemys reevesii is an important cultivated aquatic animal in China. It has values for food and Chinese medicine. In the paper, it was used to study on the pituitary gland of Chinemys reevesii which was 3-year-old female individual with weight between 325g to 490g by microscope and transmission electron microscope. The results showed that there were two major portions of the pituitary gland, the handle-shaped neurohypophsis and the oval adenohypophsis. As the neurohypophsis was situated over the tail region of adenohypophsis, the pituitary gland of the turtle belonged to dorsoventral style. The nerve lobe of the neurohypophsis was not developed enough. The adenohypophsis was further divided into pars distalis（PD） and pars intermedia（PI） . There were some characteristic vacuoles of sinusoid in pars intermedia. The pars distalis was composed of three main kind of cells, acidophilia, basophil and chromophobe. Under transmission electron microscopy, the pars distalis of adenohypophysis mainly had 5 secretory hormone cell types, including growth hormone （GH） cell, prolactin （PRL） cell, thyrotropin （TSH） cell, adrenocorticotrophic hormone （ACTH） cell, gonadotrophin （GTH） cell and non-secretory type folliculo-satellite cell （FS）. It was the most different that Chinemys reevesii had big nucleus and less secretory granules in the growth homone cell from other animals. These were possibly associated with the biological characters of slow growth and long-live life in Chinemys reevesii.