[Insulin-like growth factors I and II in follicular and oocyte maturation].
Insulin-like growth factors I and II are synthesized from animal and human follicles. Their reproduction is FSH-, LH- and oestrogen-dependent. Growth hormone is also involved. IGF-I receptor numbers increase in the presence of FSH, while estradiol has a synergic effect. IGF-I and IGF-II stimulate growth of different follicular cell elements. TGF-alpha has the same activity but seems to be mediated by an increase in IGFs. Conversely, TGF beta and activin inhibit follicular growth accompanied by a reduction in IGFs. In contrast to TGF alpha, IGFs do not cause acquisition of meiotic competence. Injection of IGF-I into cultures of prepuberal splenic primary follicles reduced IGF-II production.
Franchimont
P
P
Département d'Endocrinologie, C.H.U. B.23, Liège, Belgique.
Hazout
A
A
Menezo
Y
Y
Colette
J
J
D000818:Animals; D005260:Female; D006107:Granulosa Cells / Q000378:metabolism; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis* / Q000378:metabolism; D007335:Insulin-Like Growth Factor II / Q000096:biosynthesis*; D016014:Linear Models; D009865:Oocytes / Q000254:growth & development / Q000378:metabolism*; D006080:Ovarian Follicle / Q000254:growth & development / Q000378:metabolism*; D010053:Ovary / Q000502:physiology; D051381:Rats; D012016:Reference Values
D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II