Effects of gonadotropins upon the incidence and kinetics of meiotic maturation of macaque oocytes in vitro.

The specific aim of this study was to determine the effects of gonadotropins in vitro upon the incidence of and precise time interval to germinal vesicle breakdown (GVB) and extrusion of the first polar body (PB1) in oocytes from nonstimulated rhesus monkeys. Cumulus-enclod germinal vesicle (GV) stage oocytes from 10 normal, cycling rhesus monkeys in the follicular phase of the menstrual cycle were cultured with either: (1) 1.0 micrograms/ml human follicle-stimulating hormone (hFSH), (2) 10 micrograms/ml human luteinizing hormone (hLH), (3) 1.0 microgram/ml hFSH and 10 micrograms/ml hLH, or (4) no gonadotropins (controls). Oocytes (n = 234) were examined at 3-hr intervals from 0 to 21 hr and at 4-hr intervals from 24 to 52 hr for GVB and PB1. Neither the incidence of GVB (hFSH: 63.5%; hLH: 56.1%; both gonadotropins: 63.1%; no gonadotropins: 53.6%) nor extrusion of PB1 (hFSH: 41.3%; hLH: 36.4%; both gonadotropins: 36.9%; no gonadotropins; 31.9%) differed (P > 0.05) among treatments. The time to GVB was accelerated (P < 0.05) by gonadotropins (hFSH: 10.8 +/- 1.7 hr; hLH: 10.1 +/- 1.8 hr; both gonadotropins: 8.8 +/- 1.1 hr) when compared to controls (17.4 +/- 2.0 hr). However, the time interval to extrusion of PB1 did not differ (P > 0.05) among treatments (hFSH: 32.3 +/- 1.2 hr; hLH: 35.1 +/- 1.4 hr; both gonadotropins: 35.2 +/- 1.3 hr; no gonadotropins: 34.1 +/- 1.2 hr). The mean interval to extrusion of PB1 was 34.1 +/- 0.6 hr.(ABSTRACT TRUNCATED AT 250 WORDS)