Gonadotropin Stimulation of Porcine Ovarian Ornithine Decarboxylase in Vitro: The Role of 3′, 5′-Adenosine Monophosphate

Juraj Osterman, Laurence M. Demers, James M. Hammond

Research output: Contribution to journalArticlepeer-review

27 Scopus citations

Abstract

The role of cAMP as a mediator of gonadotropin stimulation of ovarian ornithine decarboxylase (ODC) activity was studied in granulosa cells isolated from small (1–2 mm) porcine ovarian follicles. These cells responded to both FSH and LH with significant increases in intracellular concentration of cAMP. At concentrations of gonadotropins which were saturating for the induction of ODC activity, FSH was a more potent stimulator of both cAMP production and ODC activity than LH. iV.O'-Dibutyryl cAMP (1.0–10.0 HIM) caused a dose-dependent stimulation of ODC activity which equaled the maximal effect of LH but was significantly less effective than the saturating dose of FSH. 8- Bromo-cAMP was more potent than N, O'-dibutyryl cAMP and as effective as FSH as an inducer of ODC activity. Addition of theophylline, a phosphodiesterase inhibitor, to the incubation medium resulted in a dosedependent inhibition of ODC activity in both control and gonadotropin-stimulated cells. In contrast, 1- methyl, 3-isobutyl xanthine, another phosphodiesterase inhibitor, potentiated effects of both submaximal and maximal effective doses of gonadotropins while producing no effect on basal ODC activity of these cells. The results of this study are consistent with the concept that cAMP can mediate gonadotropin stimulation of ODC in porcine granulosa cells. In addition, this study shows the importance of proper selection of cAMP analogs and phosphodiesterase inhibitors, and their concentration in studying such effects.

Original languageEnglish (US)
Pages (from-to)1718-1724
Number of pages7
JournalEndocrinology
Volume103
Issue number5
DOIs
StatePublished - Nov 1978

All Science Journal Classification (ASJC) codes

  • Endocrinology

Fingerprint Dive into the research topics of 'Gonadotropin Stimulation of Porcine Ovarian Ornithine Decarboxylase in Vitro: The Role of 3′, 5′-Adenosine Monophosphate'. Together they form a unique fingerprint.

Cite this