Tryptophan catabolism by tryptophan pyrrolase in rat liver. The effect of tryptophan loads and changes in tryptophan pyrrolase activity.

Tryptophan catabolism by tryptophan pyrrolase in rat liver. The effect of tryptophan loads and changes in tryptophan pyrrolase activity.

We investigated how changes in tryptophan pyrrolase activity and tryptophan loads affect the breakdown of tryptophan was estimated by injecting rats with [ring-2-14-C]tryptophan and measuring respiratory 14-CO2. We concluded, contrary to previous reports, that induction of tryptophan pyrrolase definitely will increase the rate of tryptophan breakdown. Tryptophan loads also increase tryptophan b...

Tryptophan Catabolism by Tryptophan Pyrrolase in Rat Liver THE EFFECT OF TRYPTOPHAK LOADS AKD CHAKGES IN TRYPTOPHAN PYRROLASE ACTIVITY*

We investigated how changes in tryptophan pyrrolase activity and tryptophan loads affect the breakdown of tryptophan by tryptophan pyrrolase. Breakdown of tryptophan was estimated by injecting rats with [ring-ZJ%]tryptophan and measuring respiratory 14C02. We concluded, contrary to previous reports, that induction of tryptophan pyrrolase definitely will increase the rate of tryptophan breakdown...

Determination of tryptophan pyrrolase activity in rat liver homogenates.

Tryptophan pyrrolase in haem regulation

1. Rat liver tryptophan pyrrolase activity is enhanced by a hormonal-type mechanism during the first 2 days of starvation and by a substrate-type mechanism during the subsequent 2 days. 5-Aminolaevulinate synthase activity is also enhanced during the first 2 days of starvation, but returns thereafter to values resembling those observed in the fed rat. Treatments that prevent or reverse the enha...

The independence of hydrocortisone and tryptophan inductions of tryptophan pyrrolase.

The activity of the mammalian liver tryptophan pyrrolase (peroxidase-oxidase) (1) was greatly increased after the injections of tryptophan (2). It was later found that increased liver enzyme levels could be produced by various stressing conditions and by injection of such substances as histidine and tyrosine (3) and histamine and adrenaline (4) in intact animals, and by adrenocorticotropic horm...