Eagleson G W, McKeown B A
Cell Tissue Res. 1978 May 18;189(1):53-66. doi: 10.1007/BF00223121.
The prolactin-producing cells are the first hormone-producing cells of the pars distalis to be differentiated within Ambystoma gracile. They first appear when the larvae attain a length of approximately 3.0 cm snout to vent length (SVL). Thyrotropes are observed as the next chromophilic cells to appear, and they occur when the larvae are approximately 4.5 cm SVL. Both thyrotropes and lactotropes increase in numbers until metamorphosis. Gonadotropes begin to appear when larvae attain a size of 5.0 cm SVL and become extremely abundant when larvae are in excess of 7.0 cm SVL. Animals, generally, exhibit the greatest number of thyrotropes just prior to the mean size for metamorphosis, and metamorphosing animals exhibit a dramatic reduction in the number of thyrotropes. Neotenous larvae have an abundant number of thyrotropes which are mainly located along the caudal periphery of the pituitary.
催乳素分泌细胞是细口钝口螈远侧部最早分化的激素分泌细胞。它们首次出现时，幼体从吻端到泄殖腔的长度（SVL）约为3.0厘米。促甲状腺激素细胞是接下来出现的嗜色细胞，当幼体SVL约为4.5厘米时出现。促甲状腺激素细胞和催乳激素细胞的数量在变态前都会增加。促性腺激素细胞在幼体达到5.0厘米SVL时开始出现，当幼体超过7.0厘米SVL时变得极为丰富。一般来说，动物在接近变态平均大小之前促甲状腺激素细胞数量最多，而正在变态的动物促甲状腺激素细胞数量会急剧减少。幼态延续的幼体有大量促甲状腺激素细胞，主要位于垂体的尾侧周边。
