Embryonic development of the pituitary gland in the chick.
Pituitary glands of chicken, from stages 20 (70 approximately 72 h of incubation) to 46 (20 days) of Hamburger and Hamilton (1951), were studied by immunocytochemical and histological stainings and India ink injection into blood vessels. Using the distribution pattern of 6 types of immunoreactive adenohypophyseal cells and the location of pituitary stalk as guideposts, we found how specific areas in the epithelium of Rathke's pouch differentiate into specific regions of the adenohypophysis at 20 days. In the sagittal plane, the walls of Rathke's pouch were tentatively divided into the upper part (A(1) + A(2)) and lower part (A(3)) of the anterior wall, and the posterior wall (P(1) + P(2) + P(3)). The cephalic lobe was mainly assembled by the proliferation of parenchymal cells in the areas A(2) + A(3) + P(2) of Rathke's pouch epithelia at 3 days of incubation. The caudal lobe was derived from A(1) + P(1) + P(3). The pars tuberalis was derived from A(1) + A(2). Thus, the avian adenohypophysis is established at 13 days, though the blood supply to the pars distalis is established at 20 days. Therefore, the cephalic lobe and caudal lobe of the pars distalis and the pars tuberalis of the chicken adenohypophysis are derived from specific areas of the cell cords of Rathke's pouch at 3 days of incubation.
Sasaki
Fumihiko
F
Department of Veterinary Anatomy, Graduate School of Agriculture and Biological Sciences, Osaka Prefecture University, Sakai, Japan. sasaki@vet.osakafu-u.ac.jp
Doshita
Ayumi
A
Matsumoto
Yoshiki
Y
Kuwahara
Sachi
S
Tsukamoto
Yasuhiro
Y
Ogawa
Kazushige
K
D000818:Animals; D002454:Cell Differentiation; D002642:Chick Embryo; D007124:Immunoenzyme Techniques; D010902:Pituitary Gland / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D010908:Pituitary Hormones, Anterior / Q000378:metabolism
D010908:Pituitary Hormones, Anterior