BACKGROUND The majority of oocytes in the mammalian ovary are dormant oocytes that are enclosed in primordial follicles by several somatic cells, which we refer to as primordial follicle granulosa cells (pfGCs). Very little is known, however, about how the pfGCs control the activation of primordial follicles and the developmental fates of dormant oocytes. RESULTS By targeting molecules in pfG...

In mammalian ovaries, a fixed population of primordial follicles forms during the perinatal stage and the oocytes contained within are arrested at the dictyate stage of meiotic prophase I. In the current study, we provide evidence that the level of cyclic AMP (cAMP) in oocytes regulates oocyte meiotic prophase I and primordial folliculogenesis in the perinatal mouse ovary. Our results show that...

The mechanisms that regulate the gradual exit of ovarian follicles from the non-growing, primordial pool are very poorly understood. A better understanding of the signals that initiate follicular growth in mammals, and of the conditions necessary for sustained growth of early preantral follicles in vitro, could have practical implications for contraception, alleviation of infertility, and regul...

background: a study on the migration characteristics of 238u, 210po, 232th and 40k within the soil to the wild plants in the western ghats were carried out. materials and methods: concentrations of these radionuclides were measured in different depths of soil and from different species by employing gamma ray spectrometer and alpha counter. results: the activity concentration of these radionucli...

background: a field study on the transfer of primordial radionuclides 238u, 232th, 40k and fallout radionuclides 210po in different plant species in tropical forest of western ghats environment is presented. material and methods: the top storey, second storey, shrubs and epiphytic plant species were chosen and concentration of these radionuclides in plant and soil were measured by employing gam...

It had been known for decades that primordial follicles in mammalian ovaries are assembled with definite numbers and represent the ovarian reserve throughout the reproductive life. Intra-oocyte PI3K/mTOR pathways have been indicated to play a central role on the activation of primordial follicles. Genetic modified mouse models with chronic activation of PI3K/mTOR signals in primordial oocytes s...

Whereas FSH action is critical for the growth of preantral follicles, its role in the development of primordial follicles is controversial. The objective of the present study was to evaluate whether perinatal (fetal through early postnatal) FSH action is needed for the formation of primordial follicles, which first appear in the hamster ovary on the 7th to 8th day of postnatal life. A single do...

Neurotrophins are growth factors that are known to have a role in promoting cell survival and differentiation. The focus of the current study is to examine the role of neurotrophins in regulating ovarian primordial follicle development. Ovaries from 4-day old rats were placed into organ culture and cultured for 10 days in the absence or presence of neurotrophin-3 (NT3), brain-derived neurotroph...

An ovarian follicle is composed of an oocyte and surrounding theca and granulosa cells. Oocytes are stored in an arrested state within primordial follicles until they are signaled to re-initiate development by undergoing primordial-to-primary follicle transition. Previous gene bionetwork analyses of primordial follicle development identified a number of critical cytokine signaling pathways and ...

BACKGROUND Primordial ovarian follicles, which are often present in the ovaries of premature ovarian failure (POF) patients or are cryopreserved from the ovaries of young cancer patients who are undergoing gonadotoxic anticancer therapies, cannot be used to generate mature oocytes for in vitro fertilization (IVF). There has been very little success in triggering growth of primordial follicles t...