Effect of activin-a on goat granulosa cell steroidogenesis.
Growth factors are said to play a significant role in the development of ovarian follicles. We wished to measure the content of one growth factor, activin-A in goat ovarian follicles, and study its effect on goat granulosa cells steroidogenesis. The follicular fluid content of activin-A from small, medium and large antral follicles was determined by two-site enzyme immunoassay. The results showed that activin-A concentration in the follicular fluid increased as the size of the follicle increased and, thus, may act as a local regulator of follicle development. To examine this possibility, the effect of increasing concentration of activin-A (0, 1, 10, 100 ng/mL) on differentiated goat granulosa cells steroidogenesis was evaluated in vitro for 48 hours in a chemically defined medium. Activin-A treatment resulted in a significant inhibition of progesterone production concomitant with a significant stimulation of estradiol production. These results were confirmed by time-effect of 50 ng/mL activin-A on goat granulosa cells steroidogenesis for 24, 48 and 72 hours. Granulosa cells displayed differential steroidogenic responses to activin-A, estradiol production becoming enhanced and progesterone production suppressed. Based on these findings, it appears that activin-A is a local regulator of goat granulosa cell steroidogenesis, and may act to promote granulosa cell differentiation and inhibit its luteinization.
Shidaifat
F
F
Department of Basic Veterinary Medical Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, Irbid. falah@just.edu.jo
D028341:Activins / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000096:biosynthesis* / Q000378:metabolism; D005260:Female; D015571:Follicular Fluid / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D006041:Goats / Q000378:metabolism / Q000502:physiology*; D006107:Granulosa Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D028322:Inhibin-beta Subunits / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D006080:Ovarian Follicle / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D011374:Progesterone / Q000096:biosynthesis* / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology
D011994:Recombinant Proteins; C422405:activin A; D028341:Activins; D011374:Progesterone; D004958:Estradiol; D028322:Inhibin-beta Subunits