Fig. 6. Carbenoxolone completely blocks dye coupling in cultured granulosa cells whereas its inactive analog does not. Follicles were cultured for 24 hours without drug (A,B), with 200 µM glycyrrhizic acid (C,D) or with 200 µM carbenoxolone (E,F), then tested for dye coupling using Lucifer Yellow. The asterisk in A,C and E indicates the injected cell. O, oocyte. Bar, 50 µm.