title: Development of thyroid-stimulating hormone beta subunit-producing cells in the chicken embryonic pituitary gland.
abstract: In previous studies, the distribution of thyrotropes in the chicken pituitary gland has been analyzed by immunohistochemistry using heterologous antibodies. In this study, we examined the distribution of thyroid-stimulating hormone beta subunit-immunopositive (TSHbeta-ip) cells and the expression of TSHbeta mRNA in the pituitary glands of chicken embryos by immunohistochemistry using a specific antiserum to the chicken TSHbeta, in situ hybridization and RT-PCR. Immunohistochemical and morphometric analyses revealed that the TSHbeta-ip cells first appeared on embryonic day 10 (E10) in the pituitary gland and were mainly distributed in the cephalic lobe and that the cell density on E20 was almost 4 times greater than that on E10. The chicken TSHbeta-ip cells could be classified into two types based on morphological characteristics: round-shaped cells and club-shaped cells, which have long cytoplasmic processes. In situ hybridization analysis revealed that TSHbeta mRNA-expressing cells were expressed from E9 in the cephalic lobe and that the extent of TSHbeta mRNA-expressing cells coincided with that of TSHbeta-ip cells. RT-PCR also showed that TSHbeta mRNA was expressed from E9 and that Pit-1 mRNA was expressed from E5. These results clearly demonstrated that the expression of chicken TSHbeta mRNA starts on E9, that TSHbeta-ip cells appear on E10, mainly in the cephalic lobe, and that TSHbeta-ip cells can be classified into two cell types (round- and club-shaped cells).
authors.affiliation: Department of Regulation Biology, Faculty of Science, Saitama University, Sakura, Saitama, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Nakamura
authors.forename: Atushi
authors.initials: A
authors.lastname: Iwasawa
authors.forename: Hinako
authors.initials: H
authors.lastname: Kidokoro
authors.forename: Masazumi
authors.initials: M
authors.lastname: Komoda
authors.forename: Jun
authors.initials: J
authors.lastname: Zheng
authors.forename: Yoko
authors.initials: Y
authors.lastname: Maseki
authors.forename: Kinji
authors.initials: K
authors.lastname: Inoue
authors.forename: Takafumi
authors.initials: T
authors.lastname: Sakai
mesh_terms: D000818:Animals; D002642:Chick Embryo; D003593:Cytoplasm / Q000378:metabolism; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D010902:Pituitary Gland / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D037322:Thyrotropin, beta Subunit / Q000096:biosynthesis*; D013997:Time Factors
chemical_list: D012333:RNA, Messenger; D037322:Thyrotropin, beta Subunit