The hydrolysis of hydantoin by various tissues.

In 1912 Lewis (1) administered hydantoin to rabbits, cats, and dogs and came to the conclusion that the ring was not readily broken in the body. Gaebler and Keltch (2) some years later showed that some hydantoin was excreted as hydantoic acid after injection into dogs. Wada (3) claimed that urea was produced from hydantoin after incubation with milk or certain tissue suspensions. Finally, Kozelka and Hine (4) gave diphenylhydantoin to men and dogs and found that 1 to 5 per cent was excreted as the corresponding hydantoic acid and 10 to 27 per cent as cr-aminodiphenylacetic acid. About 30 per cent of the drug was unaccounted for. It was therefore of interest to investigate the metabolism of hydantoin and the diphenyl derivative in detail by in vitro methods.