Aniline hydroxylase

Evidence suggests that endosulfan can induce microsomal enzyme activity. Increased liver microsomal cytochrome P-450 activity was observed in male and female rats after single and multiple administrations of endosulfan (Siddiqui et al. 1987a Tyagi et al. 1984). Increased enzyme activity was observed in hepatic and extrahepatic tissues. Based on the increase in aminopyrine-A-demethylase and aniline hydroxylase activity, endosulfan has been shown to be a nonspecific inducer of drug metabolism (Agarwal et al. 1978). 

Since endosulfan is a cytochrome P450-dependent monooxygenase inducer, the quantification of specific enzyme activities (e.g., aminopyrine-A -demethylase, aniline hydroxylase) may indicate that exposure to endosulfan has occurred (Agarwal et al. 1978). Because numerous chemicals and drugs found at hazardous waste sites and elsewhere also induce hepatic enzymes, these measurements are nonspecific and are not necessarily an indicator solely of endosulfan exposure. However, these enzyme levels can be useful indicators of exposure, together with the detection of endosulfan isomers or the sulfate metabolite in the tissues or excreta. 

Misra R, Srivastava N, Misra UK, et al. 1980. Effect of endosulphan on aniline hydroxylase activity of hepatic SER in rats fed lysine, threonine deficient and supplemented rice diets. Nutrition Reports International 21 425-428. 

No adverse effect on liver microsomal activity Reduction in liver aniline hydroxylase activity liver histopathology... 

To acquire information on the intrinsic metabolic activity of aquatic organisms, liver of carp (Cyprinus carpio Linnaeus), rainbow trout (Salmo gairdneri) and freshwater snail (Cipango-paludina japonica Martens) was dissected out, homogenized in 0.1M phosphate buffer, pH 7.5, and centrifuged at 105,000 g for 60 min to obtain the microsome-equivalent (described as the microsomal fraction hereafter) fraction. The protein content of microsomal and submicrosomal (supernatant fractions by Lowry s method, microsomal P-450 content ( ), activity of aniline hydroxylase (4) and aminopyrine N-demethylase (5) were determined. 

Protein Cmg/ml) Cytochrome -P-450 (nmoles/mg) 4-OH-BA-DNP (nmoles/ min/mg) Aniline hydroxylase (nmoles/min/mg)... 

Acetone, methyl ethyl ketone (2-butanone) and methyl isobutyl ketone (4-methyl-pentan-2-one) (6.8 mmol/kg bw for 3 days) increased the hepatotoxicity of carbon tetrachloride to Sprague-Dawley rats (Raymond Plaa, 1995a) this enhancement of toxicity was coincident with increased microsomal aniline hydroxylase activity (Raymond Plaa, 1995b). In addition to the effect on cytochrome P450, acetone, but not the other ketones, increased basal canalicular membrane fluidity, as measured by fluorescence polarization of 1,6-diphenyl-1,3,5 -hexatriene or 1 - [4-(trimethylammoniumphenyl)-6-phenyl] -1,3,5 -hexa-triene (Raymond Plaa, 1996). 

In vitro inhibition of rat liver microsomal aniline hydroxylase by methylcholanthrene effect on microsomal cytochromes P-450 and bs, and NADPH cytochrome c reductase studied 490... 

P-450 and the activity of the three enzymes only in the 3-week-old rats. Six- and 10-week-old rats showed an inhibition of AHH and increased activity of aniline hydroxylase and ethylmorphine N-demethylase, which were lower than that seen after 7 days of exposure in their respective groups. The effect of the changes in the MFO enzymes on the liver is difficult to evaluate. Although the MFO system tends to process various foreign chemicals and thus be of benefit, some of the oxidized intermediary metabolites produced by the initial MFO reactions are more toxic than are the parent compounds. 

Mieyal JJ, Acherman RS, Blumer JL, Freeman LS (1976) Characterization of enzyme-like activity of human hemoglobin. Properties of the hemoglobin-P-450 reductase-coupled aniline hydroxylase system. J Biol Chem 251 3436-3441... 

CPH-treatment of rats (1200 mg/kg/d for 2 d) induced the enzymatic activities of other renal cortical drug-metabolizing enzymes such as 7-ethoxy-couma-rine-O-deethylase and cytosolic GSH-S-transferase whereas the enzymatic activities of aniline hydroxylase and aminopyrine-N-demethylase were simultaneously decreased or remained unchanged, respectively (Table 1) [74]. Treatment of male and female rats with cephaloridine (750 mg/kg/d) for two weeks to three... 

Figure 4. Reversal of decreased aniline hydroxylase, aminopyrine N-demethylase and p-nitroanisole O-demethytase activities in vitamin C deficient guinea pigs with ascorbic acid (15).

In an acute toxicity study with male rats dosed by gavage with single doses of octachlorostyrene at 1300, 1690, 2190, 2850, and 3710 mg kg test animals were sacrificed 14 days later. At all but the lowest dose, there was an increase in liver weight, hepatic microsomal aniline hydroxylase and amino-pyrine demethylase activities, serum cholesterol, and uric acid levels. 

In a chronic study, weanling Sprague-Dawley rats (20 animals of each sex per exposure group) were fed (ad libitum) diets containing 0, 0.005, 0.05, 0.5, 5.0, or 50 mg kg octachlorostyrene in diet (fed ad libitum) for 12 months. While there was some mortality, it did not appear to be related to treatment. Similarly, tumor incidence was infrequent and appeared unrelated to treatment. However, 5.0 and 50 mg kg exposures resulted in kidney effects (e.g., dose-related dilation of proximal tubules and cytoplasmic eosinophilia along with granular casts and proteinaceous losses), and induction of aniline hydroxylase and aminopyrine demethylase activities in hepatic microsomes of both sexes. At the highest exposure level only (50 mg kg ), there was a... 

Acid phosphatase Alcohol dehydrogenase Alkaline phosphatase Amine oxidase Aminopeptidase P Angiotensin-converting enzyme Aniline hydroxylase ATPase Arylsulfatase Carboxypeptidase M Cyclooxygenase Cytochrome oxidase Endothelin-converting enzyme... 

Van Dyke RA, Rikans LE. 1970. Effect of the volatile anesthetics on aniline hydroxylase and aminopyrine demethylase. Biochem Pharmacol 19 1501-1502. 

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