[Recent findings concerning follicular growth].
Recent advances in molecular genetics now enable the study in vitro of follicular maturation using human recombinants of gonadostimulins (FSH and LH) and certain autocrine and paracrine ovarian regulation factors. This is leading to reevaluation of the precise role played by the various hormonal protagonists of folliculogenesis. FSH, in the presence of low levels of LH at the start of the follicular phase, has a mitotic action on estrogen-producing granulosa cells, encourages their differentiation and activates the synthesis of their genetically-determined products (essentially somatomedin, inhibin and activin) and of the LH receptor. High LH levels, during the second half of the follicular phase, stop proliferation of granulosa cells, and, synergistically with insulin-like growth factor 1, bring about an increase in estrogen synthesis from aromatisable androgens. In common with FSH, LH facilitates the production of cybernins and of essential growth factors, as well as of preovulatory progesterone. Abnormalities of endocrine, paracrine or autocrine regulation of follicular maturation may lead to atresia. Future rational uses of human FSH and LH are obvious and involve the optimisation of ovulation induction and in vitro fertilisation in sterile women.
Cordray
J P
JP
Service d'Endocrinologie, Hôpital Notre-Dame de Bon Secours, Paris.
Merceron
R E
RE
Guillerd
X
X
Nys
P
P
D028341:Activins; D002454:Cell Differentiation / Q000502:physiology; D004967:Estrogens / Q000378:metabolism; D005260:Female; D005640:Follicle Stimulating Hormone / Q000502:physiology*; D005496:Follicular Atresia / Q000187:drug effects / Q000502:physiology; D005498:Follicular Phase / Q000502:physiology; D006107:Granulosa Cells / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D006131:Growth Inhibitors / Q000378:metabolism; D006133:Growth Substances / Q000378:metabolism; D006801:Humans; D007265:Inhibins / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000502:physiology; D007986:Luteinizing Hormone / Q000502:physiology*; D008938:Mitosis / Q000502:physiology; D009479:Neuropeptides / Q000378:metabolism; D006080:Ovarian Follicle / Q000502:physiology*; D010062:Ovulation Induction / Q000379:methods; D011374:Progesterone / Q000378:metabolism; D011974:Receptors, LH / Q000502:physiology; D013002:Somatomedins / Q000378:metabolism
D004967:Estrogens; D006131:Growth Inhibitors; D006133:Growth Substances; D009479:Neuropeptides; D011974:Receptors, LH; D013002:Somatomedins; C036580:cybernins; D028341:Activins; D011374:Progesterone; D007265:Inhibins; D007334:Insulin-Like Growth Factor I; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone
Données récentes concernant la croissance folliculaire.