title: Fraction of proliferating cells in granulosa during terminal follicular development in high and low prolific sheep breeds.
abstract: During terminal development of antral follicles, granulosa cells progressively lose their proliferative activity. Romanov (ovulation rate = 3) and Ile-de-France (ovulation rate = 1) breeds of sheep were compared for fractions of proliferating granulosa cells, determined by in vitro continuous [3H] thymidine labelling. In both breeds, the fraction of proliferating cells decreased with increasing follicular size according to a sigmoid-shaped curve. After linearization, the slope of the regression line was higher (in absolute value) in Romanov, compared to Ile-de-France ewes (p = 0.02). In vivo FSH treatment led to a decrease in the slope of the regression line in Romanov ewes only (p = 0.03). These results suggest that during terminal follicular development (1) the rate of cell cycle exit is higher in granulosa cells of Romanov, compared to lie-de-France follicles, and (2) Romanov granulosa cells are more responsive to exogenous FSH in term of proliferation. These mechanisms may underlie differential dynamics of follicular development in poly- and mono-ovulating breeds of sheep.
authors.affiliation: Physiologie de la Reproduction et des Comportements, UMR 1291 INRA-CNRS-Université F. Rabelais de Tours, Nouzilly, France.
authors.forename: C
authors.initials: C
authors.lastname: Pisselet
authors.forename: F
authors.initials: F
authors.lastname: Clément
authors.forename: D
authors.initials: D
authors.lastname: Monniaux
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006107:Granulosa Cells / Q000166:cytology*; D006080:Ovarian Follicle / Q000502:physiology*; D010060:Ovulation; D012756:Sheep; D013045:Species Specificity
chemical_list: D005640:Follicle Stimulating Hormone