Follicle-stimulating hormone activation of glycogen phosphorylase in the Sertoli cell-enriched rat testis.
Journal Article (Journal Article)
The potential role of glycogen phosphorylase in providing energy for the Sertoli cell-enriched testis has been investigated. This enzyme is detectable in testes from rats 6-54 days of age. Glycogen phosphorylase in isolated Sertoli cell-enriched testes is specifically stimulated by FSH. Maximal activation (2-fold) is obtained within 10 min after adding 0.5 micrograms FSH/ml to isolated immature testes (16 days old). There is only a 1.1-fold activation by FSH in testes from mature (34 days old) animals. The sensitivity to the gonadotropin can be restored by adding 1-methyl-3-isobutylxanthine, a phosphodiesterase inhibitor, with the FSH. Phosphorylase can be activated by effectors that mimic the actions of the two proposed mediators of FSH action, cAMP and Ca+2. Phosphorylase from testis of either age is maximally activated by an analog of cAMP, 8-bromo-cAMP. While phosphorylase is rapidly activated 1.4-fold by incubating isolated testis for 2 min with A23187, a Ca+2 ionophore, the age, time, and dose dependence of FSH activation are consistent with conversion mediated by cAMP. Phosphorylase was localized in cultured Sertoli cells by indirect immunofluorescence microscopy. Affinity-purified antiphosphorylase decorated cytoskeletal structures that resemble stress fibers, suggesting that phosphorylase may function in Sertoli cells to provide energy for cytoskeletal motility.
Full Text
Duke Authors
Cited Authors
- Slaughter, GR; Means, AR
Published Date
- October 1, 1983
Published In
Volume / Issue
- 113 / 4
Start / End Page
- 1476 - 1485
PubMed ID
- 6193956
International Standard Serial Number (ISSN)
- 0013-7227
Digital Object Identifier (DOI)
- 10.1210/endo-113-4-1476
Language
- eng
Conference Location
- United States