Effect of sodium butyrate on induction of ornithine decarboxylase activity in phytohemagglutinin-stimulated lymphocytes.

Effect of sodium butyrate on DNA synthesis and the induction of ornithine decarboxylase (EC 4.1.1.17), a rate-limiting enzyme of polyamine biosynthesis, was studied in phytohemagglutinin (PHA)-stimulated bovine lymphocytes. Millimolar concentrations of butyrate completely inhibited the incorporation of [3H]thymidine into the acid-insoluble fraction and reversibly suppressed the induction of ornithine decarboxylase. Other short-chain fatty acids were much less active than butyrate. These results suggest that the suppression of ornithine decarboxylase activity may be one of the reasons for the inhibition of DNA synthesis with butyrate in bovine lymphocytes, because our previous experimental results have shown that the induction of ornithine decarboxylase closely correlates with the DNA synthesis in growth-stimulated cells.