Norepinephrine stimulates progesterone production in highly estrogenic bovine granulosa cells cultured under serum-free, chemically defined conditions
1 Hospital Israelita Albert Einstein, São Paulo, Brazil
2 Department of Physiology, School of Medicine of Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
3 Barão de Mauá University, Ribeirão Preto, São Paulo, Brazil
4 Department of Gynecology and Obstetrics, School of Medicine of Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
5 Department of Physiological Science, Biological Sciences Institute, Universidade de Brasília, Brasília, Brazil
Reproductive Biology and Endocrinology 2012, 10:95 doi:10.1186/1477-7827-10-95Published: 22 November 2012
Since noradrenergic innervation was described in the ovarian follicle, the actions of the intraovarian catecholaminergic system have been the focus of a variety of studies. We aimed to determine the gonadotropin-independent effects of the catecholamine norepinephrine (NE) in the steroid hormone profile of a serum-free granulosa cell (GC) culture system in the context of follicular development and dominance.
Primary bovine GCs were cultivated in a serum-free, chemically defined culture system supplemented with 0.1% polyvinyl alcohol. The culture features were assessed by hormone measurements and ultrastructural characteristics of GCs.
GCs produced increasing amounts of estradiol and pregnenolone for 144h and maintained ultrastructural features of healthy steroidogenic cells. Progesterone production was also detected, although it significantly increased only after 96h of culture. There was a highly significant positive correlation between estradiol and pregnenolone production in high E2-producing cultures. The effects of NE were further evaluated in a dose–response study. The highest tested concentration of NE (10 (−7) M) resulted in a significant increase in progesterone production, but not in estradiol or pregnenolone production. The specificity of NE effects on progesterone productio n was further investigated by incubating GCs with propranolol (10 (−8) M), a non-selective beta-adrenergic antagonist.
The present culture system represents a robust model to study the impact of intrafollicular factors, such as catecholamines, in ovarian steroidogenesis and follicular development. The results of noradrenergic effects in the steroidogenesis of GC have implications on physiological follicular fate and on certain pathological ovarian conditions such as cyst formation and anovulation.