Tryptophan Pyrrolase Induction and the Influence of Adrenocorticoids<sup>1</sup>

Lee, Norman D.; Baltz, Barbara E.

doi:10.1210/endo-70-1-84

Cited by 11 publications

(1 citation statement)

References 6 publications

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“…It seems unlikely that the observed effects of (&)-amphetamine on tryptophan concentrations are mediated via some general stress mechanism. Stress increases adrenal hormone secretion which in its turn induces tryptophan pyrrolase activity (Civen & Knox, 1960;Lee & Baltz, 1962) and tryptophan hydroxylase activity (Azmitia & McEwen, 1969). However, if amphetamine induces catabolic enzymes which, in fact, it seems to do (Schubert, in preparation), the tryptophan concentration in tissues would be decreased, which is contrary to the present results.…”

Section: Eflect Of Inhibition Of Monoamine Oxidase and Tryptophan Hydmentioning

confidence: 99%

Effect of amphetamines on tryptophan concentrations in mice and rats

Schubert

Sedvall

1972

Journal of Pharmacy and Pharmacology

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(&)-Amphetamine and some of its analogues were administered intraperitoneally to mice and rats and the concentrations of tryptophan in tissues were analysed by ff uorimetric and microbiologic techniques. The concentration of tryptophan in brain was markedly increased by (+)-amphetamine and reached a maximum about 80 min after drug administration. The effect was dose-dependent with a threshold dose below 1 mg/kg. (+)-Amphetamine was significantly more potent than p-chloroamphetamine and p-hydroxyamphetamine, indicating that the changes in tryptophan concentrations might be related to the central stimulating effect of the drugs. (*)-Amphetamine delayed the disappearance from brain of intravenously administered [3H]tryptophan. Inhibition of monoamine oxidase by nialamide (1 00 mg/kg) and tryptophan hydroxylase by H 22/54 (500 nig/kg) had no effect on the tryptophan concentration in brain.In recent years attention has been paid to the possible role of tryptophan metabolism in psychiatric disorders (Jepson

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Section: Eflect Of Inhibition Of Monoamine Oxidase and Tryptophan Hydmentioning

confidence: 99%

Effect of amphetamines on tryptophan concentrations in mice and rats

Schubert

Sedvall

1972

Journal of Pharmacy and Pharmacology

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The interaction of external and internal controls on enzyme levels in liver and hepatoma

Pitot¹,

Cho²,

Lamar³

et al. 1965

J. Cell. Comp. Physiol.

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In considering the mechanisms controlling the expression of genetic information in mammalian cells, one is faced with the consideration that the multicellular organism exists in two environments. The external environment requires controls for the maintenance of nutrition and respiration. The internal environment must be maintained constant for the survival of the organism as a whole. The liver is in a unique position, with its cells subject to pressures from both internal and external environment. Several mechanisms of enzyme regulation in which one enzyme demonstrates both controls are discussed. Elimination of the portal system, the liver's direct contact with the external environment, does not alter the basic control mechanisms. However, neoplastic transformation of hepatic cells radically alters both internal and external controls. Most external controls are lost, and those that remain are in part dependent on internal control mechanisms. On the basis of previous findings, the membrane of the endoplasmic reticulum is suggested as being the site of action of the steroid hormones.

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