Follicle-stimulating hormone activation of glycogen phosphorylase in the Sertoli cell-enriched rat testis.

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 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