Effects of porcine follicular fluid on male pronucleus formation in porcine oocytes matured in vitro.
Porcine follicular oocytes, collected from antral follicles (2-5 mm in diameter) of gilt ovaries, were matured in vitro with or without porcine follicular fluid (pFF), gonadotrophins (GTH) or fetal calf serum (FCS) for 48 hours at 37 degrees C under 5% CO2 in air, and their ability of male pronucleus (mPN) formation was examined after in vitro fertilization. Formation of mPN was observed in 38.6% of penetrated oocytes matured in modified Krebs-Ringer bicarbonate solution (TYH) 18 hours after insemination. The addition of GTH into the maturation medium did not improve the proportion of mPN-formed oocytes (20-30%). In contrast, the mPN formation rate elevated significantly (59.5%) when the oocytes were cultured with pFF, and the addition of follicle-stimulating hormone (FSH) enhanced this pFF action (the rate became 81.0%). In the presence of FSH, significant pFF effect was observable at the concentration of 5%, and its efficiency was elevated with the increase of pFF concentration. When the oocytes were matured with FCS, the mPN formation rate was unchanged or decreased rather than improved (0-25%). These results suggest that pFF, but not FCS, have substance(s) stimulating the ability of mPN formation in porcine oocytes.
Naito
K
K
School of Veterinary Medicine and Animal Sciences, Kitasato University, Tokyo, Japan.
Fukuda
Y
Y
Toyoda
Y
Y
D000818:Animals; D001826:Body Fluids; D002467:Cell Nucleus / Q000187:drug effects*; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology; D003593:Cytoplasm / Q000187:drug effects; D005260:Female; D006062:Gonadotropins / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D009865:Oocytes / Q000187:drug effects / Q000254:growth & development*; D006080:Ovarian Follicle / Q000032:analysis*; D013079:Sperm Maturation / Q000187:drug effects; D013552:Swine
D003470:Culture Media; D006062:Gonadotropins