鸡胚垂体生长激素细胞的发生及其变化

Ontogeny and the developing change of pituitary growth hormone (GH) cells of chick embryos

为研究鸡胚垂体中生长激素细胞的发生及其在发育过程中的变化 ,分别在鸡胚发育的第 3 5～ 2 0 5天采集鸡胚垂体 ,用免疫组织化学方法研究鸡胚垂体中生长激素细胞的发生和细胞形态、数量、在垂体中的分布特点和在发育过程中的变化。结果表明 ,鸡胚发育中期第 9 5天可观察到少量的生长激素阳性细胞散在分布于垂体后叶 ,细胞多排列成索状或团状 ,细胞之间边界不清 ,细胞核较大。在鸡胚发育的第 12 5天以后 ,生长激素细胞的细胞浆与细胞核比值逐渐变小 ,且均匀分布于腺垂体的后叶。生长激素细胞数在鸡胚发育的第 12 5天之后显著升高 (P <0 0 1) ,在鸡胚发育的第 16 5天 ,生长激素细胞占垂体细胞总数的 9 4 %。以上结果证明鸡胚垂体中生长激素细胞增殖和分化过程主要发生在发育的中期至出壳之前 ,而生长激素细胞的分泌功能在鸡胚发育的后期最为活跃。

To determine the ontogeny of pituitary GH cells and its change during the development of chicken embryos,the pituitary gland were collected from day 3 5 (E3 5) to E20 5 of incubation, and the expression, distribution of pituitary GH were then detected by immunohistochemistry. The results showed that very few scattered GH immunopositive cells were first detected in the caudal lobe of anterior pituitary gland at E9 5 of incubation. After E9 5 of incubation, it was observed that the number of GH positive cells increased, most of which located in the caudal lobe of anterior pituitary gland, and arranged in grape. While the nuclear/cytoplasm ratio between E9 5 and E20 5 gradually decreased. Cell counting results showed that percentage of GH positive cells accounting for total cell number was about 2 % at E9 5, it then kept rising and reached 9 4 % by E16 5 of incubation. These results suggest that the function of GH is much active during the late stage of the developing embryos, and the proliferation and differentiation of pituitary GH cells mostly occur between mid incubation and before birth.