Cyclic AMP is one of the key regulators of mammalian meiosis. In the present work, realization pathways of the previously revealed modulating influence of prolactin (PRL) on the cAMP-dependent mechanisms of meiosis regulation in bovine oocytes were studied. A comparative investigation of individual and combined effects of PRL (50 ng/ml) and an activator of adenylate cyclase forskolin (FK. 20 microM) on the meiotic reinitiation and nuclear maturation completion in cumulus-enclosed and cumulus-free oocytes was performed. It has been shown that the pattern of PRL influence on the meiotic resumption in oocytes devoid of cumulus cells depends on the presence of FK in the culture medium. Furthermore, realization of this influence is not associated with the activation of cytoplasmic isoforms of protein kinase C. It has been also found that PRL inhibits the retarding action of FK on the completion of oocyte nuclear maturation in both the presence and absence of cumulus cells. The findings suggest that PRL may modulate the functioning of the cAMP-dependent mechanism of meiosis regulation by the direct action on bovine oocytes, with realization of the action being independent of the metabolic coupling of oocytes with cumulus cells.