On the Relationship between Hydroxymethylpyrimidine and Pyridoxine. IV

Effect of 2-methyl-4-amino-5-hydroxymethylpyrimidine (OMP) on the tryptophan metabolism was observed. It was found that OMP possessed antipyridoxine action characterized by the abnormal metabolism of tryptophan. Xanthurenic acid in the 24-hour urine of a rat administered orally with L-tryptophan was determined by the method of Rosen, Huff, and Perlzweig. Administration of 5mg. of OMP with L-tryptophan to intact mice resulted in the increase of xanthurenic acid in the urine. It was further found that abnormal tryptophan metabolism had occurred in the experimental rat whose growth had been inhibited by the addition of 5mg. of OMP to 25 γ of pyridoxine, as shown in the previous paper.