Studies on metabolism of vitamin A. 2. Enzymic synthesis and hydrolysis of phenolic sulphates in vitamin-A-deficient rats

Abstract

In 24 hours after the intraperitoneal injection of Na235So4 into vitamin-A-deficient and pair-fed control rats, the deficient rats, even at the plateau stage, excreted in their urine slightly more inorganic So4 and markedly less ethereal sulfates. Injection of vitamin A acetate or acid restored this changed pattern to normal. The enzyme activities of the liver and intestinal mucosa for the sulfurylation of phenols were significantly reduced in the deficient animals and the lost activity could be restored by the addition of vitamin-A alcohol or acid to the reaction mixture in vitro. The arylsulphatase C showed no change throughout the deficiency; the arylsulphatases A and Bdid not change at the plateau stage, but were markedly increased at the acute deficiency stage. It is suggested that the reduced excretion of ethereal sulfates and increased amounts of inorganic sulfate in the urine of vitamin-A-deficient rats are due to the marked loss of the sulfurylating activity caused by the deficiency.