Induction of Tryptophan Pyrrolase in Rat Liver by Physiological Amounts of Hydrocortisone and Secreted Glucocorticoids

Abstract
Assays of the fully activated tryptophan pyrrolase in rat liver show that the enzyme level is increased in 5 hr. to a 10-fold maximum by 0.25 mg of administered hydrocortisone or by the stimulation of adrenal gland secretion. Both inductions cause higher levels in male than female rats. The tryptophan pyrrolase level can serve as an index of the physiological secretion of glucocorticoids.