Only a minute fraction of ovarian follicles present in a foetal ovary will complete the path to ovulation. The majority of the follicles will instead undergo atresia, a hormonally controlled apoptotic process. Apoptosis occurs throughout follicle development, with an extensive reduction in the number of follicles present at birth. Interestingly, this drastic reduction is not present among preov...

Studies of mice with targeted disruptions of specific connexin genes have revealed that at least two connexins, connexin37 (Cx37) and connexin43 (Cx43), play essential roles in ovarian follicle development. To explore the respective roles of these two connexins in gap-junctional communication between the developing murine oocyte and its surrounding cumulus granulosa cells, we used confocal immu...

Follicular atresia has been examined previously by various biochemical and histological methods. The aim of this study was to compare, for the first time, detection of granulosa cell apoptosis by biochemical DNA analysis and microscopic examination of fresh granulosa cell morphology with the established method of detecting atresia by histology in equine follicles. DNA extracted from granulosa c...

introduction: recent evidence suggests that nitric oxide (no) acts as an important factor in a variety of physiological and pathological processes, including reproductive function. the purpose of the present study was to investigate whether no might significantly induce any apoptotic changes in cultured human granulosa cells. material and methods: the granulosa cells (gc) were obtained from wom...

Thyroid hormone (TH) is important for normal reproductive functions and dysregulation of TH support is associated with reproductive disorders. We have previously reported that 3,5,3'-triiodothyronine (T₃) increases follicle stimulating hormone (FSH)-induced preantral follicle growth in vitro. Interaction of hormones with apoptosis and proliferation of granulosa cells is poorly understood. The p...

Insulin and insulin-like growth factors (IGFs) have direct effects on cultured ovarian cells. These effects include stimulation of granulosa cell mitogenesis, granulosa and luteal cell progesterone production, and thecal cell androgen production and appear similar among species. However, species differences exist with regard to insulin and IGF-I effects on granulosa cell estradiol production. I...

The adult human ovary is composed of various cell types. Preovulatory follicles contain two distinct types of granulosa cells that arise during folliculogenesis as the cell populations segregate upon formation of the fluid-filled follicular antrum. The granulosa cells line in the follicle wall, reside very close to the basement membrane and are essential for estrogen production and follicular r...

The highly conserved polo-like kinases (Plks) are potent regulators of multiple functions in the cell cycle before and during mitotic cell division. We investigated the expression pattern of Plk genes and their potential role(s) in the rat ovary during the periovulatory period. Plk2 and Plk3 were highly induced both in intact ovaries and granulosa cells in vivo after treatment with the luteiniz...