title: Regulation of mouse spermatogonial stem cell self-renewing division by the pituitary gland.
abstract: Spermatogenesis originates in spermatogonial stem cells, which have the unique mode of replication. It is considered that a single stem cell can produce two stem cells (self-renewing division), one stem and one differentiating (asymmetric division), or two differentiating cells (differentiating division). However, little is known regarding how each type of division is regulated. In this investigation, we focused on the analysis of self- renewing division and examined the effect of the pituitary gland using two models of stem cell self-renewing division. In the first experiment using newborn mice, the administration of GnRH- analogue, which represses the release of gonadotropin, reduced the number of stem cells during postnatal testicular development, suggesting that the pituitary gland enhances stem cell self- renewing division. In the second experiment, however, the number of stem cells increased dramatically in hypophysectomized adult recipients after spermatogonial transplantation. Thus, the pituitary gland affects the self-renewing division of stem cells, but these contradictory results suggest that its role may be different depending on the stage of the testicular development.
authors.affiliation: Horizontal Medical Research Organization, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: Mito
authors.initials: M
authors.lastname: Kanatsu-Shinohara
authors.forename: Takeshi
authors.initials: T
authors.lastname: Morimoto
authors.forename: Shinya
authors.initials: S
authors.lastname: Toyokuni
authors.forename: Takashi
authors.initials: T
authors.lastname: Shinohara
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002455:Cell Division; D007016:Hypophysectomy; D007763:Lac Operon; D016729:Leuprolide / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010902:Pituitary Gland / Q000502:physiology*; D013091:Spermatogenesis / Q000502:physiology*; D013093:Spermatogonia / Q000166:cytology*; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology*; D013737:Testis / Q000166:cytology / Q000187:drug effects / Q000254:growth & development
chemical_list: D016729:Leuprolide