Abstract
Tryptophan and it's metabolites, such as kynurenine, kynurenic acid, N-methylpyridone carboxamide in 24 hours urine were determined after an oral administration of 2g of L-tryptophan in patient of Cushing's syndrome. Increases of urinary kynurenine and N-methylpyridone carboxamide were observed in these patients before operation, but after the total adrenalectomy or removal of tumor, the excretion of tryptophan metabolites returned to normal. The convertion rate of tryptophan was revealed to be very high in Cushing's patients. When pyridoxal phosphate was given to these patients, the urinary excretion of kynurenine, kynurenic acid and xanthurenic acid decreased, both in before and after the operation, while N-methylpyridone carboxamide increased.
