Drug treatment of neonates and infants and its long-term consequences on drug responses have emerged in recent years as amajor challenge for health care professionals. In the current study, we use phenobarbital as a model drug and mouse as an in vivo model to demonstrate that the dose of phenobarbital and age of treatment are two key factors for the persistent induction of gene expression and c...

The phenomenon of enzyme induction (enzymatic adaptation) has been observed in a variety of micro-organisms. One of the most carefully studied examples, largely the work of Jacques Monod and his colleagues at the Institut Pasteur, is the induction of the synthesis of the enzyme j3-galactosidase in the bacterium Escherichia coli.", 2 This enzyme, not otherwise present in appreciable amounts, is ...

The role of metabolic activation/deactivation reactions during development is evaluated in relation to developmental pharmacology and toxicology. Enzyme systems evaluated include the mixed-function oxidases (aryl hydrocarbon hydroxylase and oxidative demethylation), epoxide hydration and conjugation (glutathione conjugation, sulfation, and glucuronidation). Placental transfer and milk secretion...

The ability of antimony and antimony-containing parasiticidal agents to enhance the rate of heme degradation in liver and kidney was investigated. Trivalent antimony was shown to be an extremely potent inducer of heme oxygenase, the initial and rate-limiting enzyme in heme degradation, in both organs, whereas the pentavalent form was a weak inducer of this enzyme. The ability of antimony to ind...

Acetylcholinesterase, an erythroid marker constitutively ex pressed in K-562 cells, can be further induced by sodium butyrate. The highest level of acetylcholinesterase induction is reached in =3 days, in parallel with increased hemoglobin expres sion. Acetylcholinesterase induction is reversible, and repeated addition of butyrate is necessary to maintain a high level of the enzyme. Actinomycin...

Supplementing the salts-glucose medium of Escherichia coli with adenine initiates induction of adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4), growth inhibition, and an increased potential for the net deamination of adenine. The extent and duration of these events are proportional to the initial adenine concentration and are dependent upon adenylate pyrophosphorylase and repression ...

Previous papers of this series have demonstrated that induction of tyrosine oc-ketoglutarate transaminase of rat liver can be attributed to adrenocortical hormone (1) and described extensive purification of the transaminase from normal and induced livers (2). The present report describes experiments in which the induction phenomenon was analyzed with a highly specific antiserum prepared against...

Corticotropin-releasing factor (CRF) and norepinephrine (NE) mediate many hormonal, autonomic, and behavioral effects of acute stress, and it is possible that an interaction between these neurotransmitters could underlie neuronal adaptations in response to chronic stress. To test this hypothesis, the influence of chronically administered CRF and a specific CRF antagonist, alpha-helical CRF, on ...

Acetylcholinesterase, an erythroid marker constitutively expressed in K-562 cells, can be further induced by sodium butyrate. The highest level of acetylcholinesterase induction is reached in approximately equal to 3 days, in parallel with increased hemoglobin expression. Acetylcholinesterase induction is reversible, and repeated addition of butyrate is necessary to maintain a high level of the...

The hormonal induction of glutamine synthetase (EC 6.3.1.2) in embryonic neural retina tissue in vitro is blocked preferentially and reversibly by proflavine (3,6-diaminoacridine) in the absence of cell or DNA replication; cell viability is not affected, and the synthesis of total cellular proteins and RNA is only slightly reduced. In the induction of this enzyme, there is a rapid increase in t...