The effects of acute and chronic nicotine hydrogen (+)-tartrate administration and subsequent withdrawal on rat liver tryptophan pyrrolase activity and their comparison with those of morphine, phenobarbitone and ethanol

Acute administration of nicotine hydrogen (+)-tartrate enhances the activity of rat liver tryptophan pyrrolase by a hormonal mechanism. Chronic nicotine treatment inhibits, and subsequent withdrawal enhances, the pyrrolase activity. The inhibition during chronic treatment is not due to a defective apoenzyme synthesis nor a decreased cofactor availability. Regeneration of liver NADP+ in vitro and in vivo reverses the inhibition. Chronic nicotine administration increases the liver NADPH concentration. The above effects of nicotine resemble to a remarkable degree those previously shown for morphine, phenobarbitone and ethanol. All effects are compared, and their possible significance in relation to drug dependence is discussed.

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The regulation of rat liver tryptophan pyrrolase activity by reduced nicotinamide-adenine dinucleotide (phosphate). Experiments with glucose and nicotinamide

Biochemical Journal ◽

10.1042/bj1560381 ◽

1976 ◽

Vol 156 (2) ◽

pp. 381-390 ◽

Cited By ~ 36

Author(s):

A A B Badawy ◽

M Evans

Keyword(s):

Drinking Water ◽

Rat Liver ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Chronic Administration ◽

Glucose Effect ◽

Tryptophan Pyrrolase ◽

Subsequent Withdrawal ◽

Phenazine Methosulphate

1. Chronic administration of glucose or nicotinamide in drinking water inhibits the activity of rat liver tryptophan pyrrolase, and subsequent withdrawal causes an enhancement. The enzyme activity is also inhibited by administration in drinking water of sucrose, but not fructose, which is capable of preventing the glucose effect. 2. The inhibition by glucose or nictinamide is not due to a defective apoenzyme synthesis nor a decreased cofactor availability. 3. The inhibition by nicotinamide is reversed by regeneration of liver NAD+ and NADP+ in vivo by administration of fructose, pyruvate or phenazine methosulphate. Inhibition by glucose is also reversed by the above agents and by NH4Cl. Reversal of inhibition by glucose or nicotinamide is also achieved in vitro by addition of NAD+ or NADP+. 4. Glucose or nicotinamide increases liver [NADPH]. [NADP+] is also increased by nicotinamide. [NADPH] is also increased by sucrose, but not by fructose, which prevents the glucose effect. Phenazine methosulphate prevents the increase in [NADPH] caused by both glucose and nicotinamide. 5. It is suggested that the inhibition of tryptophan pyrrolase activity by glucose or nicotinamide is mediated by both NADPH and NADH.

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In Vivo and in Vitro Characterization of Chlorzoxazone Metabolism and Hepatic CYP2E1 Levels in African Green Monkeys: Induction by Chronic Nicotine Treatment

Drug Metabolism and Disposition ◽

10.1124/dmd.106.010363 ◽

2006 ◽

Vol 34 (9) ◽

pp. 1508-1515 ◽

Cited By ~ 18

Author(s):

Anna M. Lee ◽

Jiang Yue ◽

Rachel F. Tyndale

Keyword(s):

Nicotine Treatment ◽

Chronic Nicotine ◽

In Vitro Characterization ◽

Chronic Nicotine Treatment ◽

Green Monkeys

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Studies of the Stability in Vivo and in Vitro of Rat Liver Tryptophan Pyrrolase

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)96999-1 ◽

1965 ◽

Vol 240 (12) ◽

pp. 4609-4620 ◽

Cited By ~ 16

Author(s):

Robert T. Schimke ◽

E.W. Sweeney ◽

C.M. Berlin

Keyword(s):

Rat Liver ◽

Tryptophan Pyrrolase ◽

The Stability

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The effects of salicylate on the activity of rat liver tryptophan pyrrolase in vitro and in vivo

Biochemical Journal ◽

10.1042/bj1230171 ◽

1971 ◽

Vol 123 (2) ◽

pp. 171-174 ◽

Cited By ~ 14

Author(s):

A. A.-B. Badawy ◽

M. J. H. Smith

Keyword(s):

Enzyme Activity ◽

Rat Liver ◽

Binding Sites ◽

Actinomycin D ◽

Sodium Salicylate ◽

Progressive Increase ◽

Tryptophan Pyrrolase ◽

Enzyme Ratio

1. Salicylate, in concentrations of 0.05mm and above, inhibits the basal activity of tryptophan pyrrolase in homogenates of rat liver and the activity induced by cortisol but not that induced by tryptophan. The inhibition is abolished by adding haematin to the reaction mixtures. 2. The intraperitoneal injection of 400mg of sodium salicylate/kg in the rat causes a decrease in the tryptophan pyrrolase activity in the liver at 30min, the activity is restored to normal at 2h, increases to sixfold after 5h and returns to the basal value at 12h. The activation of the enzyme by salicylate is prevented by the administration of cycloheximide but not by pretreatment with actinomycin D. The effects of the combined injection of salicylate and cortisol are additive, whereas those of salicylate plus tryptophan are not. The injection of salicylate causes a progressive increase in the holo-/apo-enzyme ratio and an increased content of tryptophan in the liver over a period of 3h. 3. It is suggested that salicylate inhibits tryptophan pyrrolase activity in vitro and in vivo by interacting with iron protoporphyrins and causes a later enhancement of the enzyme activity in vivo by a mechanism involving the release of tryptophan from its binding sites on circulating albumin and on other proteins.

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