title: Cell-type-specific localization of transforming growth factor-beta 2 and transforming growth factor-beta 1 in the hamster ovary: differential regulation by follicle-stimulating hormone and luteinizing hormone.
abstract: Cell-type-specific localization and gonadotropin regulation of transforming growth factor-beta 1 (TGF-beta 1) and transforming growth factor-beta 2 (TGF-beta 2) in the hamster ovary were evaluated immunohistochemically under three conditions: (1) during the estrous cycle (Day 1 = estrus; Day 4 = proestrus); (2) after the blockade of periovulatory gonadotropin surges by phenobarbital, and (3) after FSH and/or LH treatment of long-term hypophysectomized hamsters. Ovarian TGF-beta 1 activity was primarily localized in theca and interstitial cells. The activity increased moderately but significantly after the preovulatory LH surge and reached a peak at 0900 h, Day 2 h; oocytes showed considerable activity. TGF-beta 1 immunoreactivity subsequently fell to low levels in theca-interstitial cells through 0900 h, Day 4. Significant TGF-beta 2 immunoreactivity appeared after the surge, mainly in the granulosa cells of both preantral and antral follicles; a few interstitial cells surrounding preantral follicles showed discrete staining. TGF-beta 2 immunoreactivity in granulosa cells and in interstitial cells next to preantral follicles reached a peak at 0900 h, Day 1, and persisted up to 0900 h, Day 2; oocytes showed no staining. Phenobarbital treatment blocked the appearance of TGF-beta 1 and TGF-beta 2 immunoreactivities at 1600 h, Day 4; however, a rebound in immunoreactivities was observed with the onset of the surge after a 1-day delay. Replacement of LH to long-term hypophysectomized hamsters resulted in a marked increase in TGF-beta 1 immunoreactivity in the interstitial cells, but FSH, although it induced follicular development, did not influence ovarian TGF-beta 1 activity. Treatment with FSH, however, induced a massive increase in TGF-beta 2 immunoreactivity in the granulosa cells of newly developed antral and preantral follicles but not in the interstitial cells; LH, on the other hand, had no significant effect on TGF-beta 2 activity. Treatment with FSH and LH combined resulted in a dramatic increase in TGF-beta 2 immunoreactivity in granulosa and interstitial cells and in TGF-beta 1 in theca and interstitial cells comparable to their peak activity in intact animals. Western analyses substantiated the presence of TGF-beta 1 and TGF-beta 2 in the hamster ovary and the specificity of immunolocalization. These studies, therefore, provide critical evidence that TGF-beta 1 and TGF-beta 2 in the hamster ovary are expressed in specific cell types and that their expression is differentially regulated by LH and FSH, respectively.
authors.affiliation: Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Omaha 68198-4515.
authors.forename: S K
authors.initials: SK
authors.lastname: Roy
authors.forename: C
authors.initials: C
authors.lastname: Ogren
authors.forename: C
authors.initials: C
authors.lastname: Roy
authors.forename: B
authors.initials: B
authors.lastname: Lu
mesh_terms: D000818:Animals; D015153:Blotting, Western; D006224:Cricetinae; D004971:Estrus / Q000502:physiology; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D007016:Hypophysectomy; D007150:Immunohistochemistry; D007986:Luteinizing Hormone / Q000494:pharmacology*; D010053:Ovary / Q000737:chemistry* / Q000166:cytology* / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000032:analysis* / Q000235:genetics / Q000378:metabolism
chemical_list: D016212:Transforming Growth Factor beta; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D010634:Phenobarbital