Insulin-like growth factors (IGFs) are potent mitogens for FRTL5 rat thyroid follicular cells. IGFs also synergize the independent mitogenic effects of thyrotropin-stimulating hormone (TSH) and other agents that increase intracellular AMP concentration. We examined whether FRTL5 cells and M12 cells, a TSH-independent mutant cell line derived therefrom, secrete IGF that regulates the growth of r...

The interactions of peptide and steroid hormone signaling cascades in the ovary are critical for follicular growth, ovulation, and luteinization. Although the pituitary gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) play key regulatory roles, their actions are also dependent on other peptide signaling pathways, including those stimulated by insulin-like growth fac...

Involvement of insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) in ovarian folliculogenesis has been extensively studied during the last decade. In all mammalian species, IGF-I stimulates granulosa cell proliferation and steroidogenesis. The concentrations of IGF-I and -II do not vary during terminal follicular growth and atresia. In contrast, the levels of IGFBP-2 and -4, a...

BACKGROUND Comparisons of follicular development and hormonal profile in the same women during and after lactational amenorrhoea (LA) are scarce. We report follicular growth, pituitary and ovarian hormone serum levels in the same women during LA and in follicular phases after resumption of menstrual cyclicity. METHODS Serum samples were obtained from 10 women during LA between days 60 and 89 ...

Potential antimicrobial activity of follicular fluid and its selectivity remains open questions in field of human and animal reproduction. In our work we examine antimicrobial activity of porcine follicular fluid on coliform bacteria, as Gram-negative, and B. cereus, as Gram-positive, by incubation of different dilatations of bacteria with follicular fluid in cultivation medium and microbiologi...

The mechanism governing the number of follicle-stimulating hormone (FSH) peaks and emerging follicular waves in ruminants remains unknown. The main purpose of the present study was to examine the relationships between progesterone (P(4)) levels, circulating concentrations of FSH and antral follicular development throughout the interovulatory interval in sheep. We retrospectively analyzed and co...

The aim of this review is to summarize the interactions between the oocyte and its surrounding granulosa cells which are involved in the control of oocyte growth or apoptosis as well as those playing a key role in the ability of the oocyte to undergo nuclear (resumption as meiosis to reach the MII stage) or cytoplasmic maturation (ability to fertilize and develop to the blastocyst stage). The r...

BACKGROUND Anti-Müllerian hormone (AMH) is member of the transforming growth factor-beta superfamily of growth factors. AMH is detected in serum from women of reproductive age and its levels vary slightly with the menstrual cycle, reaching the peak value in the late follicular phase. The present study was undertaken to assess the effect of controlled ovarian stimulation on AMH secretion by the ...

In mouse ovaries, the first wave of folliculogenesis perinatally starts near the medullary region, which directs the initial round of follicular growth soon after birth. At the same time, cortical primordial follicles start forming in the ovarian surface region, and then some are cyclically recruited for the second and subsequent rounds of follicular growth. Recent studies suggest different dyn...

the families of tgf-β proteins are the most important growth factors in the ovary for growth and differentiation of early ovarian follicles. three related oocyte-derived members of the transforming growth factor-β superfamily namely growth differentiation factor 9 (gdf9), bmp15 and bmpr-ib have been shown to be essential for follicular growth and ovulation. different mutations in the gdf9 gene ...