The secretion of oxytocin and arginine-vasopressin was demonstrated in bovine granulosa cell culture. It was found that dbcAMP or 3-isobutyl-1-methyl-xanthine (an inhibitor of intracellular cAMP metabolization) additions increased both oxytocin and vasopressin release. The Ca2+ ionophore A23187 also stimulated, while the Ca2+ channel blocker verapamil inhibited the secretion of both nonapeptide hormones. These results suggest the involvement of cAMP- and Ca(2+)-dependent intracellular mechanisms in the stimulation of both oxytocin and vasopressin secretion by bovine granulosa cells.