The resumption of the meiotic cycle (maturation) induced by 1-methyladenine in prophase-arrested starfish oocytes is indicated by the breakdown of the germinal vesicle and is characterized by the increased sensitivity of the Ca2+ stores to inositol 1,4,5-trisphosphate (InsP3) to InsP3 starting at the animal hemisphere (where the germinal vesicle was originally located) and propagating along the...

This study examines the timing of changes in chromosome configurations of pig oocytes derived from small antral follicles of follicular and/or inactive stage donors using modified 199 medium supplemented with gonadotropins (Follicle Stimulating Hormone (FSH), 10 IU/ml; Human Chorionic Gonadotropin (hCG), 10 IU/ml) and Glucosamine (0.539 mg/ml). Oocytes (n = 1,215) were fixed at the end of 3 hou...

Maturation in vitro of oocytes of the newt, Notophthalmus viridescens, is inducible with progesterone after in vivo treatment of females with gonadotropin; few oocytes mature in vitro in the absence of such gonadotropin treatment. Chromosomes of most large oocytes of animals not receiving gonadotropin are still in the lampbrush condition; chromosomes from gonadotropin-treated animals are shorte...

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...

Using oocytes isolated from juvenile and adult mice, we have examined the qualitative patterns of protein synthesis during growth and during meiotic maturation of these oocytes. Oocytes were cultured in a denned medium in the presence of [^Slmethionine and radioactively labelled proteins were separated by SDS-polyacrylamide gel electrophoresis and detected by fluorography. The results of these ...

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...

the changes of total calcium content of persian sturgeon, acipenser persicus follicles were investigated during different stages of germinal vesicle migration. total calcium content increased during maturation and ripening of the oocytes i.e. migration of nucleus toward the animal pole. according to data, the total calcium of follicles with polarization index (pi: the ratio of the distance of t...

Background The utilization of immature oocytes derived from stimulated cycles could be of great importance, specially for urgent fertility preservation cases. The aim of the current study was to determine whether in-vitro maturation is more successful before or after the vitrification of these oocytes. MaterialsAndMethods The study was performed in a private IVF center. 318 germinal vesicle (GV...