[Effect of ionophore A23187 and verapamil on RNA and DNA polymerase activity in rat liver nuclei].

It was shown that verapamil and Ca(2+)-ionofor A23187 essentially inhibited the activity of RNA-polymerase in isolated nuclei of rat liver, while DNA-polymerasing activity was inhibited only after the addition of verapamil. These phenomena were not found after treatment of nuclei with 1% triton X-100. The inhibition of RNA synthesis was also found after the addition of Ca(2+)-ionofor A23187 but not verapamil to nuclei which envelope was disrupted by freezing-thawing procedure. The data obtained suggest that Ca(2+)-ionofor A23187 and verapamil affected RNA and DNA synthesis in isolated nuclei.