Effects of human pituitary FSH isoforms on mouse follicles in vitro.
The effects of human FSH glycoforms on mouse follicle development and function in vitro were analysed, and an attempt was made to relate markers of follicular maturation to the expression of immunolocalized connexin (Cx) 43 and Cx26-based gap junctions. Three FSH fractions comprising discrete pI ranges [7.10-5.99 (pool I), pI 5.62-4.95 (pool II) and <3.75 (pool III)] were studied. Pool I produced the strongest effect on preantral granulosa cell proliferation and oestradiol production, and was highly effective for stimulating antral formation; this isoform also evoked a peripheral distribution of Cx43-containing gap junctions. Pool II was effective in promoting preantral granulosa cell proliferation but required higher FSH doses. This particular isoform provoked a more central distribution of Cx43-containing gap junctions, which was associated with a lower oestradiol production and less effective antral formation. Pool III was the least active for all markers of follicle development, and this was associated with minimal induction of Cx43-based gap junctions. The effects of the three FSH isoform pools on Cx26 expression were similar. The pattern of differences strongly suggests that FSH isoforms have complementary and specific actions on developing follicles, and that a shifting stage specific balance of isoforms is required for optimal follicle development.
Barrios-de-Tomasi
J
J
Research Unit in Reproductive Medicine, Hospital de Ginecoobstetricia 'Luis Castelazo Ayala', IMSS, Mexico City, Mexico.
Nayudu
P L
PL
Brehm
R
R
Heistermann
M
M
Zariñán
T
T
Ulloa-Aguirre
A
A
D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival; D000072259:Connexin 26; D018031:Connexin 43 / Q000378:metabolism; D017630:Connexins / Q000378:metabolism; D004967:Estrogens / Q000378:metabolism; D005260:Female; D043373:Follicle Stimulating Hormone, Human / Q000378:metabolism / Q000494:pharmacology*; D017629:Gap Junctions / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009924:Organ Culture Techniques; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development*; D010903:Pituitary Gland, Anterior / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism / Q000494:pharmacology
D018031:Connexin 43; D017630:Connexins; D004967:Estrogens; D043373:Follicle Stimulating Hormone, Human; C000607042:GJB2 protein, human; D020033:Protein Isoforms; D000072259:Connexin 26