[Mechanism of action of eserine on DNA synthesis in rat liver].

Eserine (1-2 mg/kg) decreased incorporation of the radioactive precursors into total DNA of the rat liver by 40-50%. Only high eserine cincentrations (10-5 M) effected directly the DNA synthesis in the hepatocyte nuclei. It was shown in vitro that the DNA synthesis in the nuclei of hepatocytes, isolated from the liver of rats after eserine administration (1 mg/kg), decreased significantly. A conclusion is drawn that the eserine action on the incorporation of radioactive precursors into DNA of the rat liver in vivo is localized at the level of the DNA synthesis in the nuclei. The study of the acetylcholine action on the DNA synthesis in the isolated nuclei of hepatocytes suggests that the inhibitory effect of eserine on the DNA synthesis is mediated through acetylcholine.