[Transmethylation inhibitors prevent the spontaneous reinitiation of meiosis in denuded ovocytes of mice].

Methyltransferase inhibitors such as 5'-methyl-5'-thioadenosine (MTA), 5'-deoxy-5'-isobutylthioadenosine (SIBA) and 5'-deoxy-5'-isobutylthio-3-deaza-adenosine (3-deaza-SIBA) maintain the meiotic prophase block in denuded mouse oocytes. The inhibitory effect is dose-dependent and reversible. This inhibition is potentiated by forskolin and by the phorbol 12,13 dibutyrate (PD Bu), a tumor-promoting phorbol ester.