This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by DOWNS, S. M. Articles by EPPIG, J. J. Search for Related Content PubMed PubMed Citation Articles by DOWNS, S. M. Articles by EPPIG, J. J.

Cyclic Adenosine Monophosphate and Ovarian Follicular Fluid Act Synergistically to Inhibit Mouse Oocyte Maturation^*

STEPHEN M. DOWNS and JOHN J. EPPIG

The Jackson Laboratory Bar Harbor, Maine 04609

Abstract

The relationship between cAMP and the capacity of two partially-purified fractions of porcine follicular fluid (PFF) to suppress mouse oocyte maturation was investigated. The fractions used were: 1) a low molecular weight filtrate (<10,000) derived from Amicon PM10 filtration of PFF (PM10), and 2) a fraction from Bio-Gel P2 chromatography of the PM10 filtrate (Bio-Gel) that has meiotic inhibitory activity in porcine oocytes. PM10 alone produced a transient inhibition of the maturation of both cumulus cell-enclosed and denuded mouse oocytes, as manifested by germinal vesicle breakdown. The addition of FSH or (Bu)₂cAMP to medium containing either of the PFF fractions resulted in dramatic synergism of the inhibitory effect of PFF alone in cumulus cell-enclosed oocytes. Forskolin or (Bu)₂cAMP promoted a similar synergistic response with either PFF fraction in denuded oocytes. The degree of inhibition was consistently greater in cumulus cell-enclosed than in denuded oocytes. The putative inhibitor was dialyzable through tubing having a nominal molecular weight cutoff of 1,000. Proteolysis, acid hydrolysis, or ether extraction of PM10 did not reduce its inhibitory synergism with (Bu)₂cAMP. However, inhibition was completely abolished by charcoal extraction. Steroid hormones did not mimic the PM10-induced synergism when added to (Bu)₂cAMP-containing medium in a concentration at least 14-fold greater than that present in PM10-supplemented medium. In conclusion, our results demonstrate the presence of a factor(s) in PFF that acts synergistically with a cAMP-dependent process to inhibit oocyte maturation in vitro. Furthermore, although PFF fractions suppressed the maturation of both denuded and cumulus cell-enclosed oocytes, cumulus cells appear to mediate the inhibitory activity of PFF. The data also suggest that the PFF inhibitor is a small (mol wt < 1,000) hydrophobic molecule but not a peptide or nonpolar lipid. (Endocrinology 114: 418, 1984)

Footnotes

^* This work was supported in part by National Research Service Award T32 07065 from NIH (to S.M.D.) and ACS Grant CD-27D (to J.J.E.).

To whom requests for reprints should be addressed.

Received June 13, 1983.

This article has been cited by other articles:

				M. A. Mayes, M. F. Laforest, C. Guillemette, R. B. Gilchrist, and F. J. Richard Adenosine 5'-Monophosphate Kinase-Activated Protein Kinase (PRKA) Activators Delay Meiotic Resumption in Porcine Oocytes Biol Reprod, April 1, 2007; 76(4): 589 - 597. [Abstract] [Full Text] [PDF]

				L. G. Villa-Diaz and T. Miyano Activation of p38 MAPK During Porcine Oocyte Maturation Biol Reprod, August 1, 2004; 71(2): 691 - 696. [Abstract] [Full Text] [PDF]

				M. Shimada and T. Terada FSH and LH induce progesterone production and progesterone receptor synthesis in cumulus cells: a requirement for meiotic resumption in porcine oocytes Mol. Hum. Reprod., July 1, 2002; 8(7): 612 - 618. [Abstract] [Full Text] [PDF]

				M. Shimada, T. Maeda, and T. Terada Dynamic Changes of Connexin-43, Gap Junctional Protein, in Outer Layers of Cumulus Cells Are Regulated by PKC and PI 3-Kinase During Meiotic Resumption in Porcine Oocytes Biol Reprod, April 1, 2001; 64(4): 1255 - 1263. [Abstract] [Full Text]