Multihormonal control of vitellogenesis in lower vertebrates.
The comparative approach on how and when vitellogenesis occurs in the diverse reproductive strategies displayed by aquatic and terrestrial lower vertebrates is presented in this chapter; moreover, attention has been paid to the multihormonal control of hepatic vitellogenin synthesis as it is related to seasonal changes and to vitellogenin use by growing oocytes. The hormonal mechanisms regulating vitellogenin synthesis are also considered, and the effects of environmental estrogens on the feminization process in wildlife and humans have been reported. It is then considered how fundamental nonmammalian models appear to be, for vitellogenesis research, addressed to clarifying the yolkless egg and the evolution of eutherian viviparity.
Polzonetti-Magni
Alberta Maria
AM
Department of Comparative Morphology and Biochemistry, University of Camerino, V. Camerini 2, 62032 Camerino (MC), Italy.
Mosconi
Gilberto
G
Soverchia
Laura
L
Kikuyama
Sakae
S
Carnevali
Oliana
O
D000663:Amphibians; D000818:Animals; D005260:Female; D005262:Feminization / Q000139:chemically induced; D005399:Fishes; D006066:Gonads / Q000502:physiology; D015386:Hazardous Substances / Q000633:toxicity; D006728:Hormones / Q000502:physiology*; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology; D008297:Male; D012098:Reproduction / Q000502:physiology; D012104:Reptiles; D014818:Vitellogenesis / Q000235:genetics / Q000502:physiology*; D014819:Vitellogenins / Q000096:biosynthesis* / Q000235:genetics
D015386:Hazardous Substances; D006728:Hormones; D014819:Vitellogenins