Effect of vitamin A nutritional status on the ribonucleic acids of liver, intestinal mucosa and testes of rats

Abstract

1. Vitamin A deficiency led to an increase in the oligonucleotide fraction of testes and intestinal mucosa of rats at the expense of high-molecular-weight RNA and 4S RNA, but no such changes were observed in the liver. Retinyl acetate supplementation reversed these effects in both tissues, whereas retinoic acid supplementation was almost equally effective in the mucosa but virtually ineffective in the testes. The ribonuclease activities of all the tissues remained unaffected by the above treatments. 2. The effect of vitamin A deprivation on the acceptor activity of the tRNA of the testes and intestinal mucosa was more pronounced than on the liver tRNA. The testes and mucosal tRNA of the retinoic acid-supplemented rats showed significantly lower charging capacity as compared with the retinyl acetate-supplemented ones. Here also no significant effect was observed on the liver tRNA. 3. Vitamin A deficiency caused a decrease in the percentage of poly(A) in RNA of the mucosa and testes, but not in the liver RNA. The poly(A) contents of both tissues were brought to normal by retinyl acetate supplementation; treatment with retinoic acid led to an appreciable increase in poly(A) in the mucosa, but considerably less increase in poly(A) in the testes. 4. The incorporation of H332PO4 into the rRNA and tRNA of the testes was lowered by vitamin A deficiency, but no such effects was observed in the liver RNA.