Fig. 3. Oocytes stimulate pSMAD2 in cumulus cells. Western blot immunostained for pSMAD2 and ACTB in COCs cultured in media alone or with SB431542 (10 µM) and in OOX cells cultured alone, OOX cells co-cultured with FGO and co-cultured OOX cells treated with SB431542 (10 µM) for 15 hours. Graphical representation of relative pixel intensity normalized to ACTB pixel intensity is also shown. ^a,bP<0.05, significant differences.