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PARENT SESSION Follicular Development
131
INFLUENCE OF BETA-ADRENERGIC RECEPTOR ANTAGONIST ON IN VITRO FOLLICULOGENESIS AND THECA/INTERSTITIAL CELL CULTURE.
Meethal, Kannan1, Angeles, Rowena1, Smith, Gary1, 1
ABSTRACT- Catecholamines(CA) such as norepinephrine (NE)and dopamine (DA) are present within follicular fluid. These CA may influence folliculogenesis and/or steroidogenesis. We have shown that addition of NE, DA and serotonin to media containing preantral mouse ovarian follicles significantly enhanced in vitro follicular growth. In this study we hypothesised that -adrenergic receptor antagonist, DL-propranolol (PROP) treatment would compromise in vitro folliculogenesis. Follicles were cultured in modified MEM media without (n=32) or with (n=34) PROP (50 M). Follicular diameter increased during 10 days of culture in control media (106.8 ± 2.9 to 131.7 ± 8.8; m; mean ± SE). Follicular growth was completely ablated in the presence of PROP (100.8 ± 4.3 to 102.6 ± 6.80 m). Follicular diameter was significantly greater in control compared to PROP media from day 5 to 10(P<0.05). During this culture period oocyte diameter increased in control media (56.2 ± 1.3 to 67.5 ± 0.8 m), and was significantly elevated in comparison to PROP (53.4 ± 1.8 to 61.3 ± 1.3 m; P <0.05). Propranolol treatment of follicles led to dose-dependent accumulation of lipid-like droplets in the cytoplasm of theca/interstitial cells. These droplets were stained by oil red O and extractable with chloroform:methanol (2:1)indicating their lipid nature. Similar lipid droplet accumulation was observed in isolated theca/interstitial cells cultured with PROP. Propranolol-induced accumulation of lipid droplets was reversible following culture in control media. In addition treatment of follicle-associated and isolated theca/interstitial cells with 50 M PROP reduced 3- -hydroxy steroid dehydrogenase-positive cells. In conclusion, treatment of in vitro-grown follicles with PROP compromises folliculogenesis which may be due to aberrant theca/interstitial cell function. Current studies focus on - adrenergic receptor antagonist effects on steroidogenesis during in vitro folliculogenesis.
KEY WORDS: folliculogenesis, catecholamines, theca/interstitial
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