title: Evidence for a functional bone morphogenetic protein (BMP) system in the porcine ovary.
abstract: Bone morphogenetic proteins (BMPs) play important roles in controlling fertility and ovulation rate. There is however, little information on the BMP system in the ovary of a large polyovular species. The aims of the present study were to investigate BMP-2 and -6 protein expression in the porcine ovary, their effects on granulosa cells in culture and their mechanism of action. Cells and oocytes were recovered from healthy antral follicles 2-6mm in diameter. When assessed by Western blotting, oocytes and follicular fluid contained BMP-2 and -6. In addition, BMP-2 and -6 were observed in granulosa cells and BMP-2 was also found in theca cells. Granulosa cells were cultured in a serum-free system for 144 h in the presence of increasing doses (0, 3, 30 and 100 ng/ml) of BMP-2 or BMP-6. Both BMPs suppressed progesterone production in a dose-dependent manner after 48 h (P<0.001) and 144 h (P<0.05). Only BMP-6 stimulated cell proliferation at 100 ng/ml (P<0.05). Investigation into the mechanism of action found that BMP-2 and -6 decreased cyclic adenosine monophosphate (cAMP) production (P<0.01), expression of 3beta-hydroxysteroid dehydrogenase (3beta-HSD) protein (P<0.001) and steroidogenic acute regulatory protein (StAR) (BMP-6 only; P<0.05). This supports the hypothesis that BMP-2 and -6 act as luteinization inhibitors. In conclusion, these findings provide evidence for the presence of a complex signalling mechanism in the porcine ovary and suggest that both BMP-2 and -6 may act in a paracrine manner to control granulosa cell function in this large polyovulatory species.
authors.affiliation: Division of Animal Physiology, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
authors.forename: Victoria
authors.initials: V
authors.lastname: Brankin
authors.forename: Ruth L
authors.initials: RL
authors.lastname: Quinn
authors.forename: Robert
authors.initials: R
authors.lastname: Webb
authors.forename: Morag G
authors.initials: MG
authors.lastname: Hunter
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000096:biosynthesis / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D055396:Bone Morphogenetic Protein 2; D055418:Bone Morphogenetic Protein 6; D019485:Bone Morphogenetic Proteins / Q000096:biosynthesis / Q000494:pharmacology / Q000502:physiology*; D049109:Cell Proliferation / Q000187:drug effects; D000242:Cyclic AMP / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D005260:Female; D006107:Granulosa Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D009865:Oocytes / Q000378:metabolism / Q000502:physiology*; D010750:Phosphoproteins / Q000096:biosynthesis; D011374:Progesterone / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D013552:Swine / Q000502:physiology*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000494:pharmacology / Q000502:physiology*; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D055396:Bone Morphogenetic Protein 2; D055418:Bone Morphogenetic Protein 6; D019485:Bone Morphogenetic Proteins; D010750:Phosphoproteins; D016212:Transforming Growth Factor beta; D000098682:Steroidogenic Acute Regulatory Protein; D011374:Progesterone; D000242:Cyclic AMP; D015096:3-Hydroxysteroid Dehydrogenases