title: Sertoli cells are capable of proliferation into adulthood in the transition region between the seminiferous tubules and the rete testis in Wistar rats.
abstract: Sertoli cells (SCs) play a crucial role in testis differentiation, development and function, determining the magnitude of sperm production in sexually mature animals. For over 40 years, it has been considered that these key testis somatic cells stop dividing during early pre-pubertal phase, between around 10 to 20 days after birth respectively in mice and rats, being after that under physiological conditions a stable and terminally differentiated population. However, evidences from the literature are challenging this dogma. In the present study, using several important functional markers (Ki-67, BrdU, p27, GATA-4, Androgen Receptor), we investigated the SC differentiation status in 36 days old and adult Wistar rats, focusing mainly in the transition region (TR) between the seminiferous tubules (ST) and the rete testis. Our results showed that SCs in TR remain undifferentiated for a longer period and, although at a lesser degree, even in adult rats proliferating SCs were observed in this region. Therefore, these findings suggest that, different from the other ST regions investigated, SCs residing in the TR exhibit a distinct functional phenotype. These undifferentiated SCs may compose a subpopulation of SC progenitors that reside in a specific microenvironment capable of growing the ST length if needed from this particular testis region. Moreover, our findings demonstrate an important aspect of testis function in mammals and opens new venues for other experimental approaches to the investigation of SC physiology, spermatogenesis progression and testis growth. Besides that, the TR may represent an important site for pathophysiological investigations and cellular interactions in the testis.
authors.affiliation: a Laboratory of Cellular Biology, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais , Belo Horizonte , MG , Brazil.
authors.forename: A F A
authors.initials: AF
authors.lastname: Figueiredo
authors.affiliation: a Laboratory of Cellular Biology, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais , Belo Horizonte , MG , Brazil.|b National Institute of Amazonian Research (INPA/Manaus), National Institute of Amazonian Research (INPA) , Manaus , AM , Brazil.
authors.forename: L R
authors.initials: LR
authors.lastname: França
authors.affiliation: c Department of Comparative Biosciences , University of Illinois , Urbana Champaign , IL , USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Hess
authors.affiliation: a Laboratory of Cellular Biology, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais , Belo Horizonte , MG , Brazil.
authors.forename: G M J
authors.initials: GM
authors.lastname: Costa
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001973:Bromodeoxyuridine / Q000378:metabolism; D002454:Cell Differentiation; D049109:Cell Proliferation; D005455:Fluorescent Antibody Technique; D050991:GATA4 Transcription Factor / Q000378:metabolism; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D017208:Rats, Wistar; D011944:Receptors, Androgen / Q000378:metabolism; D012152:Rete Testis / Q000166:cytology*; D012671:Seminiferous Tubules / Q000166:cytology*; D012708:Sertoli Cells / Q000166:cytology* / Q000378:metabolism*; D012741:Sexual Maturation
chemical_list: D015415:Biomarkers; D050991:GATA4 Transcription Factor; D019394:Ki-67 Antigen; D011944:Receptors, Androgen; D001973:Bromodeoxyuridine
keywords: Androgen Receptor; BrdU; GATA-4; Ki-67; Sertoli cell; p27; seminiferous tubules; transition region