摘要: synopsis. The ultimate control of amphibian gonadal function rests with environmen? tal factors mediated through the hypothalamus. It appears that ovarian growth resides in infundibular region and ovulation preoptic area. For normal temporal relationships between oocyte to occur, an intact hypothalamo-pituitary complex is necessary. uncertain whether several types pituitary basophils considered histologically as gonadotropin-producing cells are fact producing separate LH- FSH-like hormones. Perhaps concensus indicates a single hormone has both vitellogenic ovulatory functions. This stimulates estrogen synthesis secretion by follicle cells, this steroid causes oviduct hepatic biosynthesis vitellogenin, major yolk platelet precursor. Uptake lipoprotein from ihe circulation its conversion components gonadotropin, presence which results estaiblishment rapid micropinocytotic process at level surface mechanism for crystallization yolk. A sudden surge hormone, when presented fully grown oocytes leads their maturation ovulation, oviducal jelly release some species. active progestin nature, again produced cells. In review known involved hypothalamo-hypophysio-ovarian axis discussed together consideration outstanding problems possible relevance oviparity ovoviviparity amphibians found viviparous Both gametogenic endocrine functions ovary un? der control, but other lower vertebrate classes, precise nature overriding regulation cycles hypothalamus central nervous system, leaves large areas where knowledge falls short mammals. fundamental features reproduction female seem remark? ably uniform throughout vertebrates although recourse contributions symposium will indicate inter-class differences emphasis placed on various hormonal factors. t'he most significant these role estrogenic steroids mediating vitellogenesis. is, course, paramount importance all oviparous species, gonadotropins fulfill controlling regulating