HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Rhodes, R. C. Articles by Inskeep, E. K. Search for Related Content PubMed PubMed Citation Articles by Rhodes, R. C., III Articles by Inskeep, E. K.

Ovarian 3'5'-Cyclic Adenosine Monophosphate and Prostaglandins: A Sequential Comparison of Gonadotropin-Stimulated Events in Small and Large Ovine Follicles¹

West Virginia University^,4, Morgantown 26506

Abstract

Luteinizing hormone (LH) stimulates a cascade of ovarian hormonal events that culminate in ovulation. This study was designed to investigate, in sheep, sequential changes in prostaglandin (PG) E₂, PGF₂ , 6-keto-PGF₁ , and cyclic adenosine monophosphate (cAMP) in the theca, granulosa and follicular fluid of large preovulatory follicles and small nonovulatory follicles in response to LH. On d 15 postestrus, preovulatory or nonovulatory follicles were injected intrafollicularly with saline or LH. Ewes were then ovariectomized at 0, 2, 4, or 8 h postinjection. Injected follicles were excised; theca, granulosa and fluid were separated, weighed and assayed for cAMP and PG. Contents of cAMP in the theca, granulosa and fluid of preovulatory follicles increased (P < .01) 2 to 4 h after injection of LH. Increases (P < .05) in contents of PGE₂ and PGF₂ in the theca and fluid of preovulatory follicles were observed between 4 and 8 h after injection of LH. The time courses of LH-induced synthesis of PGE₂ and PGF₂ in preovulatory follicles were parallel. Luteinizing hormone had no effect on PGE₂, PGF₂ or cAMP in any compartment of small follicles. Contents of 6-keto-PGF₁ varied with time in both theca and granulosa of large and small, saline- and LH-injected follicles. Although specific increases in cAMP and PG followed an injection of LH only in large follicles, the parallel temporal relationship of PGE₂ and PGF₂ did not explain the dichotomous functions ascribed to PGE₂ and PGF₂ during the periovulatory period.

¹ Published with the approval of the Director of the West Virginia Agric. and Forestry Exp. Sta. as Scientific Paper #2087. This investigation was supported by an NIH training grant (AM07312-04) and by West Virginia Hatch Project 224 (NE-72). We thank Drs. Lawrence Levine, Norman Mason, Tom Louis and Gordon Niswender for gifts of antisera to PGF₂ , PGE₂, PGI₂, and LH, respectively.

² Present address: Dept. of Anim. and Vet. Sci., Univ. of Rhode Island, Kingston 02881.

³ Reprint requests.

⁴ Div. of Anim. and Vet. Sci.