OBJECTIVE: A role for inhibin and activin in primate oocyte maturation was investigated. DESIGN: The maturation and fertilization of rhesus monkey oocytes recovered from the excised ovaries of nine regularly cycling animals was compared for untreated germinal vesicle (GV)-intact controls versus oocytes cultured in the presence of inhibin, activin, inhibin + activin, or in a combination with follistatin. SETTING: Nonhuman primates in a research institute environment. INTERVENTIONS: Bilateral oophorectomy. MAIN OUTCOME MEASURE: Oocyte maturation from germinal vesicle breakdown (GVBD) to metaphase II (MII) and fertilization. RESULTS: Germinal vesicle breakdown, progression to MII and fertilization was monitored in oocytes cultured for 48 hours. Activin alone, at an optimum concentration of 100 ng/mL, stimulated GVBD whereas both GVBD and MII development was enhanced in the presence of inhibin + activin. The latter also accelerated the rate of maturation to MII. All treatment groups exhibited a higher incidence of GVBD compared with controls. When follistatin was added, the stimulatory effect of activin or activin + inhibin was abolished. Exposure to medium containing inhibin + activin significantly increased the percentage of MII oocytes that fertilized compared with controls (68% versus 25%, respectively). CONCLUSIONS: Inhibin and activin are potent stimulators of primate oocyte maturation, producing mature oocytes in vitro that fertilize with high efficiency.
OBJECTIVE: A role for inhibin and activin in primate oocyte maturation was investigated. DESIGN: The maturation and fertilization of rhesus monkey oocytes recovered from the excised ovaries of nine regularly cycling animals was compared for untreated germinal vesicle (GV)-intact controls versus oocytes cultured in the presence of inhibin, activin, inhibin + activin, or in a combination with follistatin. SETTING: Nonhuman primates in a research institute environment. INTERVENTIONS: Bilateral oophorectomy. MAIN OUTCOME MEASURE: Oocyte maturation from germinal vesicle breakdown (GVBD) to metaphase II (MII) and fertilization. RESULTS: Germinal vesicle breakdown, progression to MII and fertilization was monitored in oocytes cultured for 48 hours. Activin alone, at an optimum concentration of 100 ng/mL, stimulated GVBD whereas both GVBD and MII development was enhanced in the presence of inhibin + activin. The latter also accelerated the rate of maturation to MII. All treatment groups exhibited a higher incidence of GVBD compared with controls. When follistatin was added, the stimulatory effect of activin or activin + inhibin was abolished. Exposure to medium containing inhibin + activin significantly increased the percentage of MII oocytes that fertilized compared with controls (68% versus 25%, respectively). CONCLUSIONS: Inhibin and activin are potent stimulators of primate oocyte maturation, producing mature oocytes in vitro that fertilize with high efficiency.
Authors: Catherine A VandeVoort; Namdori R Mtango; Young S Lee; George W Smith; Keith E Latham Journal: Biol Reprod Date: 2009-07-29 Impact factor: 4.285