Über das Verhalten der Phenylmilchsäure in vitro und in vivo.

Abstract

Rat kidney enzyme transformed both d-phenylalanine and phenyl-lactic acid into phenyl-pyroracemic acid. When studying urines of patients with Imbecillitas phenyl-pyrouvica, if phenyl-pyroracemic acid was destroyed with ferric Fe and the urine then tested for phenylalanine, a positive reaction was obtained. When ether extraction was used to remove phenyl-pyroracemic acid, the reaction was negative. The substance which reacted with rat kidney enzyme was therefore ether soluble. Two possibilities were given: (1) there was an ether soluble ester of d-phenylalanine and (2) the ether soluble substance was phenyl-lactic acid. Feeding expts. with rat as well as with human urine examination substantiated the current view that phenyl-lactic acid was not an intermediary metabolite in the transformation of phenyl-alanine into phenyl-pyroracemic acid; it probably arose by spontaneous decomposition of the phenyl-pyroracemic acid.