[Comparative study of normal and degenerating oocytes in the golden hamster in the early stages of postnatal development. Polyovular follicules and multinuclear oocytes].
Oocyte atresia in the golden hamster ovarium was followed at successive stages of the postnatal development, from a 5th to a 40th day. Oocyte degeneration may occur in various ways: by formation of so to say Z cells (in the pachynema stage oocytes) or by nuclear pycknosis (in the pachynema and diplonema stage oocytes, and after ovarial follicles formation - at the stage of primordial and one-layered follicle). In growing ovarial follicles, the degeneration begins from the picnosis of follicular cell nuclei, or changes in zona lucida. The oocyte nucleus is not pycknosized, but undergoes series of rearrangement quicker, than in the norm, and is able to enter into meiotic divisions I and II. A mass degeneration is followed in golden hamster oocytes at the pachynema stage, being then much reduced due, probably, to a slower process of atresia in ovarial follicles. Two-or tree-nucleated oocytes with a far developed degeneration are observed. A comparative study of uni- and polyovular follicles at progessive stages of ovarium development in juvenile females has shown that the follicles develop synchronously. Unlike occytes of uniovular follicles, all the oocytes of polyovular follicles enter into the large growth period from the beginning of their formation.
D000818:Animals; D006224:Cricetinae; D005260:Female; D066298:In Vitro Techniques; D008647:Mesocricetus; D008938:Mitosis; D009865:Oocytes / Q000254:growth & development* / Q000648:ultrastructure; D006080:Ovarian Follicle / Q000254:growth & development / Q000648:ultrastructure; D010063:Ovum / Q000254:growth & development*
Sravnitel'noe issledovanie normal'nykh i degeneriruiushchikh ootsitov zolotistogo komiachka v nachale postnatal'nogo razvitiia. Poliovuliarnye follikuly i mnogoiadernye ootsity.