INVESTIGADORES
PARBORELL Maria Fernanda Agustina
artículos
Título:
Inhibin A increases apoptosis in early antral follicles in the ovary of DES-treated rats.
Autor/es:
VITALE A; OLGA GONZALEZ; F. PARBORELL; IRUSTA, GRISELDA; CAMPO S; TESONE M
Revista:
BIOLOGY OF REPRODUCTION (ONLINE)
Editorial:
Elsevier
Referencias:
Año: 2002 vol. 67 p. 1577 - 1583
ISSN:
1529-7268
Resumen:
The purpose of this study was to evaluate the role of inhibin A in follicular
development and apoptosis-related mechanisms in preantral and early antral
follicles from prepubertal diethylstilbestrol (DES)-treated rats. Granulosa cells
isolated from the ovaries of 23- to 25-day-old rats were cultured in serum-free
medium containing FSH (20 ng/ml), transforming growth factor beta (5 ng/ml), and
estradiol (50 ng/ml) in the presence or absence of different concentrations of
recombinant human inhibin A. (3)H-Thymidine incorporation was decreased in the
presence of Inh, but no significant changes were observed in progesterone and
estradiol levels in culture medium. An increase in low molecular weight DNA
fragmentation indicative of apoptosis and an increase in the levels of Bax
protein with no changes in Bcl-2 protein levels were evident in early antral
follicles incubated for 24 h with Inh. For each animal, Inh (0.5 micro g/ovary)
was injected intrabursally in one ovary, and the contralateral ovary served as a
control. Ovarian histology revealed an inhibitory effect of Inh treatment on the
follicular development induced by DES. At 24 h after Inh injection, the number of
preantral follicles was increased compared with controls, whereas the number of
early antral follicles was decreased. In addition, in vivo Inh treatment caused
an increase in the percentage of apoptotic cells in preantral and early antral
follicles. These results suggest that inhibin produced by the dominant follicle
may act as a paracrine factor inhibiting the growth of neighboring follicles,
thus participating in the mechanism of follicular selection.