Fig. 7.

cGMP levels in cumulus cells and oocytes after stimulation of freshly isolated or cultured COCs with NPPC; effect of culture with estradiol. COCs were isolated from eCG-stimulated mice. They were incubated with or without 30 nm NPPC for 1 h either immediately (freshly isolated) or after culture for 24 h (24-h culture) in medium with or without (C) estradiol (E2) (100 nm). Solid bars indicated groups not incubated with NPPC, whereas cross hatched bars show groups treated for 1 h with 30 nm NPPC (17). The left panel shows cGMP levels in the cumulus cells (CC) (fmoles per CC of one COC). The right panel shows cGMP levels in oocytes (fmoles per oocyte). Values indicate the mean ± sem of four independent experiments with at least 100 COCs assessed at each point in each experiment. Levels of cGMP not connected by the same letter are significantly different (P < 0.05).