title: Inversion of D-tryptophan to L-tryptophan and excretory patterns in the rat and chick.
abstract: The behavior of D-tryptophan in the blood plasma and the pattern of tryptophan excretion in the urine were studied in the rat and the chick. When D-tryptophan was administered orally to rats and chicks, both showed D-tryptophan in the plasma. Conversion of D-tryptophan to the L-isomer in the rat was found by an examination of plasma from the posterior vena cava and the portal vein, following stomach intubation of 100 micromoles D-tryptophan/100 g of body weight. The peak in the increase of L-tryptophan was approximately 150 nmoles/ml plasma when measured at 30 minutes after administration and the peak was 200 nmoles when measured 2 hours after administration. No conversion of D-tryptophan to the L-isomer was found in chicks. Under similar conditions, D-tryptophan was measured in the urine of rats and chicks. In rats the D-tryptophan excreted was at most 1% of the amount administered; while in chicks most of the D-tryptophan was excreted.
mesh_terms: D000818:Animals; D002645:Chickens / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D007441:Intubation, Gastrointestinal; D008297:Male; D011169:Portal Vein; D051381:Rats / Q000378:metabolism*; D013045:Species Specificity; D013237:Stereoisomerism; D014364:Tryptophan / Q000378:metabolism*; D014682:Vena Cava, Inferior
chemical_list: D014364:Tryptophan