rate of in vitro maturation of oocytes is one of the challenges of assisted reproductive techniques. in this study we investigated the effects of supplementation of cysteamine on the rate of in vitro maturation of oocytes in two different media. germinal vesicle oocytes were collected from mouse ovary and cultured in two media (tcm199 and meme) with 0, 50, 100, 200, 500 µm/ml cysteamine. number...

objective: mitochondria is a critical organelle within the cell and has important role in the oocyte development, thus the aim of this study was the comparison of mitochondrial distribution within the mouse oocyte at germinal vesicle (gv), germinal vesicle breakdown (gvbd) and metaphase ii (mii) stages using laser confocal microscopy (lscm). materials and methods: after superovulation of adult...

in order to determine the most effective hormones on the in vitro oocyte maturation (germinal vesicle breakdown - gvbd) in a hybrid sturgeon bester, ovarian follicles were incubated at the migratory nucleus stage in the presence of several steroids, gonadotropin preparations and forskolin. occurrence of gvbd and 17,20β-dihydroxy-4-pregnen-3 -one (dhp) production were followed during an expe...

Txndc9 (thioredoxin domain containing protein 9) has been shown to be involved in mammalian mitosis; however, its function in mammalian oocyte meiosis remains unclear. In this study, we initially found that Txndc9 is expressed during meiotic maturation of mouse oocytes and higher expression of Txndc9 mRNA and protein occurred in germinal vesicle (GV) stage. By using confocal scanning, we observ...

Background In vitro maturation (IVM) of human oocytes has acquired increasing attention in infertility treatment with great promise. This technique is an alternative conventional in vitro fertilization-embryo transfer (IVF-ET), and can be reduced the side effects of gonadotropin stimulation such as ovarian hyperstimulation (OHSS). Oocyte maturation is a complex process including cytoplasmic and...

Keeping the intact germinal vesicle (GV) is essential for maintaining the capacity of mammals including human. It is maintained by very complex procedures along with folliculogenesis and is a critical step for getting competent oocyte. So far, a few mechanisms involved in folliculogenesis are known but GV arrest mechanisms are largely unrevealed. Cyclic AMP, a adenosine derived substance, have ...

Germinal vesicle breakdown in mouse oocytes in vivo and in vitro has been examined by electron microscopy. In vitro oocytes were studied immediately after release from follicles and at various times (05-11 h) in culture. Approximately 30 min after oocyte release, chromatin condensation begins along the convoluted nuclear envelope (NE). Chromatin granules are common in all condensing chromosomes...

Meiotic reinitiation of the mouse oocyte is characterized by a slow entry into metaphase I, beginning with germinal vesicle breakdown and ending with spindle formation. It is accompanied by a cascade of protein kinases and phosphatases increasing protein phosphorylation. The activation of histone H1 kinase and that of the mitogen-activated protein kinase p42 have been compared during spontaneou...

In amphibians, as well as in other vertebrates, occytes start to mature under the action of hypophyseal gonadotropic hormones. (In this paper the term 'maturation' implies the transformation into ripe eggs of oocytes that have finished growing.) In the course of maturation the oocytes themselves and the follicle cells surrounding them undergo changes; the changes of these two cell types are not...