Effects of granulosa cells and gonadotrophins on meiotic and developmental competence of oocytes in vitro in non-stimulated rhesus monkeys.

Specific aims of this study were to determine effects of granulosa cells and gonadotrophins on the meiotic and developmental competence in vitro of oocytes from non-stimulated rhesus monkeys. Oocytes (368) were obtained from small antral follicles (class 1: 700-999 microns; class 2: 1000-2500 microns) dissected from excised ovaries of 10 follicular and three luteal phase monkeys. Oocytes were cultured in one of four treatment groups: (i) granulosa cells (4 x 10(6) live cells/ml) + gonadotrophins (5 micrograms/ml follicle stimulating hormone and 10 micrograms/ml luteinizing hormone), (ii) granulosa cells alone, (iii) gonadotrophins alone, or (iv) controls (no granulosa cells or gonadotrophins). Mature oocytes were inseminated and cultured until arrest of embryo development. Meiotic and developmental capacity was greater (P < or = 0.05) for oocytes from class 2 compared with class 1 follicles and from luteal compared with follicular phase monkeys. Culture of oocytes with gonadotrophins alone during in-vitro maturation improved (P < or = 0.01) activation and cleavage through the 5-8-cell stage (46.5%). Culture with granulosa cells alone during in-vitro maturation augmented progression of embryos to the morula stage (6.3%). The combination of granulosa cells+gonadotrophins enhanced (P < or = 0.01) nuclear maturation, but had no effects on developmental capacity beyond those of either treatment alone. In conclusion, both granulosa cells and gonadotrophins during in-vitro maturation have stimulatory effects on the meiotic and developmental competence of oocytes from non-stimulated macaques in vitro.