Enhancement of ribonucleic acid synthesis by chromium(III) in mouse liver

Abstract

The effect of Cr(III) administration on hepatic RNA synthesis in mice was studied. It was found that Cr accumulated in mouse liver. Forty-eight hours after intraperitoneal injection of CrCl 3 (0.005–5 mg Cr/kg body weight) approximately 10% of the administered dose perg of tissue remained. The accumulated Cr was still retained 64 days after administration (5 mg Cr/kg) with only a slight decrease. Approximately 20% of the hepatic Cr was detected in the nuclei. By administering CrCl 3, RNA synthesis in mouse liver was markedly enhanced without altering the pool size of nucleotides. This enhancement was dose-dependent and statistically significant at doses of 0.05 ( p < 0.05), 0.5 ( p < 0.01), and 5 mg Cr/kg ( p < 0.01), and remained so for at least 16 days after administration of 5 mg Cr/kg. The syntheses of DNA and protein in mouse liver were not significantly changed by CrCl 3 administration. On the other hand, Cr(VI) administration did not enhance but rather inhibited RNA synthesis in mouse liver. These results suggest that Cr(III) specifically enhances RNA synthesis in mouse liver.