Effect of dithiothreitol on meiotic maturation of mouse oocytes in vitro: dependence of the effect on N6,O2'-dibutyryl Adenosine 3',5'-cyclic monophosphate.

The inhibitory effect of dithiothreitol on meiotic maturation of mouse oocytes in vitro is a function of the intracellular dibutyryl cyclic AMP concentration. Inhibition of nuclear (germinal vesicle) breakdown by dibutyryl cyclic AMP is reversed upon transfer of oocytes to plain culture medium, whereas, transfer to medium containing dithiothreitol results in continued inhibition. Dithiothreitol significantly enhances the effectiveness of dibutyryl cyclic AMP as an inhibitor of meiotic maturation. These results suggest that the reported effect of sulfhydryl reducing agents on membrane dissolution and reconstitution, in both meiotic and mitotic cells, may be attributed to their influence on intracelular levels of cyclic AMP.