Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “AMINOPYRINE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
PubMedDate not supplied

Antipyrine clearance, aminopyrine N-demethylase, and bilirubin UDP-glucuronyl transferase activity in patients with amoebic liver abscess.

Three indices of drug metabolism, antipyrine clearance in vivo, and aminopyrine N-demethylase and bilirubin UDP-glucuronyl transferase activity in liver biopsies, were studied in fifteen patients with amoebic liver abscess (with and without jaundice). The mean (+/- S.E.) antipyrine half-life in patients with jaundice was 21.64 (+/- 1.52) h and in patients without jaundice was 19.36 (+/- 0.93) h. It was significantly prolonged in both groups of patients as compared to controls (11.63 +/- 0.86 h). It showed a good correlation with serum albumin (p less than 0.01), prothrombin time index (p less than 0.01), and aminopyrine N-demethylase (p less than 0.05). Aminopyrine N-demethylase was found to be decreased in patients without jaundice but no significant change could be observed in patients with jaundice. Bilirubin UDP-glucuronyl transferase showed no significant change in either of the groups.

Adolescent↗
PubMedDate not supplied

Comparison of different methods expressing results of the aminopyrine breath test.

Different methods of expressing the results of the aminopyrine CO2 breath test (ABT) were compared to determine the method that would be most sensitive for evaluating liver function. The patient population included health controls (n = 22); patients with mild (4), moderate (9), and severe (7) alcoholic liver disease; and patients with chronic persistent hepatitis (7), chronic active hepatitis (18), chronic active hepatitis with bridging (18), and chronic active hepatitis with cirrhosis (17). The ABT was performed with 2 micro Ci [14C]aminopyrine or 2 mg per kg [13C]aminopyrine, and the results were expressed as the instantaneous labeled CO2 excretion rates at 30, 60, 90, and 120 min after the dose, the maximum excretion rate, and the 120-min cumulative excretion. The 30-min parameter had the highest sensitivity toward moderate alcoholic hepatitis, severe alcoholic hepatitis, chronic active hepatitis with bridging, and chronic active hepatitis with cirrhosis (96%); however, when the ABT was repeated in six normal controls with 225 ml of orange juice, the 30-min rate was significantly reduced (7.8 +/- 1.3 vs. 5.6 +/- 1.2% dose per hr), and the rate of false-positive test results was increased (0 of 6 vs. 2 of 6) indicating that gastric delay influenced the 30-min parameter. The 60-min excretion rate, maximum rate, and 120-min cumulative excretion were the next most sensitive expressions of the ABT, and were not altered by the small gastric load. Of these three expressions, the 60-min parameter was the most convenient because it required fewer samples and a shorter test period.

Adult↗
PubMed1990

Lack of interference by sorbitol with aminopyrine breath test.

The effect of sorbitol on the aminopyrine breath test was investigated in 13 patients with various liver diseases given a bolus dose of sorbitol 20 mg.kg-1 i.v. 30 min after 14C-aminopyrine and 13 patients without the sorbitol bolus who also underwent an aminopyrine breath test. The time course of 14CO2 exhalation after the bolus of sorbitol did not differ from that in the control group.

Adolescent↗
PubMed1982

Plasma levels of parent drug and metabolites in the intravenous aminopyrine breath test.

[Dimethylamine-14C]-aminopyrine was given i.v. to 5 healthy volunteers and 5 medical patients in a dose of 1.67 mg/kg, containing 0.02 micro Ci/kg 14C. In 4 volunteers the experiment was repeated using oral administration of aminopyrine. Exhalation of 14CO2 was followed for 6-10 h and plasma levels of the drug and of its metabolites 4-methylamino-antipyrine, 4-amino-antipyrine, 4-acetylamino-antipyrine, 4-formylamino-antipyrine, were measured by thin-layer chromatography. The concentration-time profiles of the metabolites mostly failed to conform to a Bateman function. Areas under the curves from 1 to 6 h after dosing indicated distinct interindividual differences in metabolite patterns even in the absence of disturbed liver function, whereas the intraindividual data were closely reproducible. In most subjects, the area of formylamino-antipyrine exceeded that of the acetyl analogue. The metabolite patterns did not exhibit a consistent relationship to the ratios between 14CO2 half-life in breath and aminopyrine half-life in plasma, which varied from 1.4 to 3.2.

Adult↗
PubMed1982

Breath 14CO2 after intravenous administration of [14C]aminopyrine in liver diseases.

The determination of of 14CO2 in breath after oral administration of [14C]aminopyrine has been proposed as a quantitative liver function test. In order to shorten the procedure and avoid misinterpretations related to variable rates of intestinal absorption, the [14C]aminopyrine breath test (ABT) was performed after intravenous administration of [14C]aminopyrine in 21 controls and 89 patients with biopsy-proven liver disease. The specific activity of the first hour sample corrected for body weight (SA1) was the most discriminant expression of breath data. The SA1 value, expressed as the percentage of the administered dose, was 0.86 +/- 0.1% (mean +/- SD) in controls and significantly less in patients (0.46 +/- 0.31%). Low values were observed in patients with untreated chronic active hepatitis (0.16 +/- 0.13%), alcoholic cirrhosis (0.2 +/ 0.15%0, and untreated postnecrotic cirrhosis (0.47 +/- 0.17%). In contrast, normal values were obtained in chronic persistent hepatitis (0.86 +/- 0.13%) and 58% of noncirrhotic alcoholic liver diseases (0.83 +/- 0.27%). The results of duplicate studies were reproducible and SA1 correlated with other conventional liver function tests, including 45-min BSP retention. Among these, ABT was the most sensitive screening test for the presence of cirrhosis, especially in alcoholic patients, where it allowed a sharp distinction between cirrhotic and noncirrhotic cases. The results obtained in chronic hepatitis suggested that ABT may provide a reliable index of the activity of the disease. In our hands, intravenous ABT, performed over a 1-hr period, was a fast, sensitive, and discriminant liver function test.

Administration, Oral↗
PubMed1978

[Increased demethylation of aminopyrine under long-term treatment with anticonvulsive drugs (author's transl)].

Demethylation of aminopyrine was measured in 25 healthy controls and 19 epileptics on long-term treatment with anticonvulsants by the 14C-aminopyrine breath test. Compared to controls epileptics exhibited increased cumulative 14CO2-exhalation rates (88.7% at 30 min, 62.6% at 2 h and 24.8% at 8h) following ingestion of 2 mu Ci 14C-aminopyrine. The results suggest that long-term treatment with antiepileptic drugs results in increased demethylating function of the liver which can be easily detected by a simple breath analysis technique like decreased demethylation in chronic liver disease.

Aminopyrine↗
PubMed1987

Inhibition of 14C-aminopyrine accumulation in isolated rabbit gastric glands by the H2-receptor antagonist HOE 760 (TZU-0460).

Acid secretion in isolated rabbit gastric glands was measured by means of the 14C-aminopyrine accumulation technique. Hoe 760 (TZU-0460) and Hoe 062, the desacetylated compound of Hoe 760, caused a concentration-dependent reduction of histamine (100 microM) induced aminopyrine-accumulation. The IC50-values were 3.16 +/- 0.84 microM (n = 5) and 1.58 +/- 0.6 microM (n = 6) for Hoe 760 and Hoe 062, respectively. In comparison an IC50 of 9.0 +/- 0.72 microM (n = 6) was obtained for cimetidine and 3.3 +/- 1.4 microM (n = 5) for ranitidine. The IC50-values of ranitidine, Hoe 760 and Hoe 062 were significantly different (p less than 0.05) from cimetidine. The addition of increasing concentrations of Hoe 760 to the histamine concentration-response curve caused a parallel rightward shift. The transformation of these concentration-response curves according to Arunlakshana and Schild indicated that this inhibition was caused by a competitive antagonism of the histamine receptor on the parietal cell. In agreement with these findings the dbc-AMP stimulated aminopyrine accumulation remained unaffected by the H2-receptor antagonists.

Aminopyrine↗
PubMed1995

[13C]Aminopyrine breath test detects altered liver metabolism caused by low-dose oral contraceptives.

The [13C]aminopyrine breath test measures hepatic mixed function oxidase activity. The cumulative percent dose recovered over 2 hr is a sensitive indicator of hepatic dysfunction; values < or = 7.0% have been shown to indicate severe liver disease. Previous studies have suggested that the test results may be influenced by the use of oral contraceptives steroids. We compared the results from five non-oral contraceptive-using women with those from 31 women whose duration of oral contraceptive steroid usage ranged from 4 to 204 months. The women were taking one of four oral contraceptive formulations that differed in the amounts of estrogen (20, 35, or 50 micrograms with 1 mg progesterone) and progesterone (35 micrograms estrogen with stepped levels of progesterone of 0.5, 0.75, and 1.0 mg). The [13C]aminopyrine breath test was performed on days 21 and 28 of the menstrual cycle. Cumulative percent dose recovery values among the normal menstrual cycle of non-oral contraceptive steroid-using women were 12.1 +/- 1.6 and 11.8 +/- 1.5% (mean +/- SD). In contrast, oral contraceptive steroid users showed a marked reduction in cumulative percent dose recovery at 21 days, averaging 6.1 +/- 2.3% (P < 0.001), and returned to normal values (10.2 +/- 3.5%) at 28 days in most women(seven days after oral contraceptive steroid usage was paused). The adverse impact on hepatic mixed function oxidase by oral contraceptive formulations did not differ on the basis of estrogen or progesterone content. The adverse impact of oral contraceptive usage on the mixed function oxidase activity measured by the [13C]aminopyrine breath test must be considered for women of childbearing potential.

Adult↗
PubMedDate not supplied

Diabetes in female rats; changes in liver microsomal aminopyrine N-demethylase and UDP-glucuronyl transferase activities.

Short or long term diabetes in female rats produced remarkable activation of aminopyrine N-demethylation, inhibition of oestrone and p-nitrophenol glucuronidation and no changes in morphine UDP-glucuronyltransferase activity in vitro. Km and Vmax for these reactions were determined. Insulin treatment partially antagonized diabetes activation of aminopyrine N-demethylation: it restored decreased UDP-glucuronyltransferase activities for oestrone and p-nitrophenol only in long term and short term diabetes, respectively. Insulin also markedly inhibited morphine glucuronidation. Triton X-100 also displayed a differential pattern of activation for the glucuronidation reactions in liver microsomes of diabetic rats. Results suggest that diabetes in female rats may increase the actual amount of enzyme protein for aminopyrine metabolism and to decrease that for oestrone and p-nitrophenol.

Aminopyrine N-Demethylase↗
PubMed1984

Inhibition of gastric acid secretion by a phorbol ester: effect of 12-O-tetradecanoylphorbol-13-acetate on aminopyrine accumulation by rat parietal cells.

12-O-tetradecanoylphorbol-13-acetate ( 32nM ) inhibits aminopyrine accumulation induced by dibutyryl cyclic AMP or by histamine plus 3-isobutyl-1-methylxanthine in isolated rat parietal cells, but a significant effect on carbachol-stimulated aminopyrine accumulation is only seen at higher concentrations of the phorbol ester. 12-O-tetradecanoylphorbol-13-acetate ( 32nM ) does not affect aminopyrine accumulation or glucose oxidation in unstimulated cells, nor does it alter the ability of cells to exclude trypan blue. The phorbol ester may trigger a specific, and novel, parietal cell system capable of modulating the acid secretory response to histamine.

Aminopyrine↗
PubMed1989

Attenuation of low dose phenobarbital induction of hepatic microsomal aminopyrine N-demethylase activity in rats by cimetidine.

Cimetidine, a substituted imidazole, is an inhibitor of hepatic cytochrome P-450-mediated drug metabolism in rats and humans. We investigated the effect of cimetidine on phenobarbital induction of hepatic microsomal aminopyrine N-demethylase activity in the rat. Phenobarbital induction of aminopyrine N-demethylase was log-linear in the range of 1-6 mg/kg/day and the ED50 was approximately 3 mg/kg/day. Cimetidine 75 mg/kg (four times a day) attenuated the induction of aminopyrine N-demethylase activity by 58% in low dose (3 mg/kg/day) but not in high dose (40 mg/kg/day) phenobarbital treated rats. This result could not be explained by residual inhibition of enzyme activity by cimetidine and suggests that cimetidine affects the induction of hepatic cytochrome P-450 by low dose phenobarbital.

Aminopyrine N-Demethylase↗
PubMedDate not supplied

Effects of sodium salicylate, aminopyrine and chlorpromazine on behavioral temperature regulation.

To characterize drug actions on thermoregulatory processes it is necessary to know whether compounds which alter body temperature also cause changes in thermoregulatory motivation. In the present experiments the effects of sodium salicylate, aminopyrine and chlorpromazine (CPZ) on rectal temperature (Tre) and behavior were measured in rats trained to escape heat and obtain cooling. All three drugs produced hypothermia in a 23 degree C environment but the effects upon behavior suggest that the compounds have different actions. Sodium salicylate (60-300 mg/kg) increased the amount of time spent responding to escape heat and obtain cooling so that Tre was held below control levels. Aminopyrine (12.5-75 mg/kg) did not alter thermoregulatory motivation even though it caused marked hypothemia. The time spent responding decreased after CPZ (2 and 3 mg/kg) so that drug-induced hypothermias were compensated. The results suggest that sodium salicylate influences the central mechanisms of physiological and behavioral temperature control whereas CPZ affects either peripheral thermoeffectors or central effector pathways without disrupting thermoregulatory motivation. Aminopyrine is presumed to act on central temperature controls to lower body temperature and, at the same time, to reduce the significance of the low body temperature to behavior.

Aminopyrine↗
PubMed2005

Determination of compound aminopyrine phenacetin tablets by using artificial neural networks combined with principal components analysis.

A method for simultaneous, nondestructive analysis of aminopyrine and phenacetin in compound aminopyrine phenacetin tablets with different concentrations has been developed by principal component artificial neural networks (PC-ANNs) on near-infrared (NIR) spectroscopy. In PC-ANN models, the spectral data were initially analyzed by principal component analysis. Then the scores of the principal components were chosen as input nodes for the input layer instead of the spectral data. The artificial neural network models using the spectral data as input nodes were also established and compared with the PC-ANN models. Four different preprocessing methods (first-derivative, second-derivative, standard normal variate (SNV), and multiplicative scatter correction) were applied to three sets of NIR spectra of compound aminopyrine phenacetin tablets. The PC-ANNs approach with SNV preprocessing spectra was found to provide the best results. The degree of approximation was performed as the selective criterion of the optimum network parameters.

Aminopyrine↗
PubMed1986

Quantitative liver function in the elderly assessed by galactose elimination capacity, aminopyrine demethylation and caffeine clearance.

Hepatic function was assessed in 13 healthy elderly subjects, 71-88 years of age, with three quantitative tests of liver function. The galactose elimination capacity was significantly (P less than 0.05) lower in the elderly (6.08 +/- 1.30 mg X min-1 X kg-1, mean +/- SD) than in a group of 70 subjects under 40 (7.48 +/- 0.94 mg X min-1 X kg-1) and 11 subjects between the age of 40 and 70 (7.08 +/- 0.68 mg X min-1 X kg-1). The demethylation of aminopyrine as assessed by the aminopyrine breath test, and the systemic clearance of caffeine, two measures of microsomal function, demonstrated a comparable decrease but showed much more interindividual variation. Caffeine clearance decreased from 1.49 +/- 0.44 ml X min-1 X kg-1 in young adults to 0.97 +/- 0.39 ml X min-1 X kg-1 (P less than 0.01) in the elderly, and the demethylation of aminopyrine decreased from 0.79 +/- 0.15 to 0.62 +/- 0.20% dose X kg X mmol-1 (P less than 0.05). Our data indicate that aging is associated with a loss of the functioning mass of hepatocytes. The decrease in drug metabolism parallels the loss of functional mass but shows more interindividual variation probably reflecting the many genetic and environmental factors influencing these tests of microsomal function.

Adult↗
PubMed2001

A piezoelectric biomimetic sensor for aminopyrine with a molecularly imprinted polymer coating.

A molecularly imprinted polymer for aminopyrine was synthesized using methacrylic acid as functional monomer. The polymer was employed as the recognition element of a piezoelectric bulk acoustic wave biomimetic sensor for aminopyrine. Influencing factors were investigated in detail and optimized. This sensor exhibited high selectivity and sensitivity to aminopyrine. The response range of the sensor was between 5.0 x 10(-8) and 1.0 x 10(-4) M with a detection limit of 2.5 x 10(-8) M in the aqueous system. Scatchard analysis with UV spectrophotometry showed that the same class of binding sites was formed in the molecularly imprinted polymer in the studied concentration range, and the dissociation constant and the apparent maximum number of these binding sites were estimated to be 2.29 mM and 165.0 mumol g-1 dry polymer, respectively. Impedance analysis was employed to verify the imprinting effect and lack of variation in the viscoelasticity of the polymer coating during detection.

Aminopyrine↗
PubMed2001

Influence of pH on the permeability of p-toluidine and aminopyrine through shed snake skin as a model membrane.

The influence of pH on the permeability of p-toluidine (pKa, 5.3) and aminopyrine (pKa, 5.0) through shed snake skin as a model membrane was studied. The pH was adjusted to several values, and the solubility of the drugs in each donor was measured. Flux rates and permeability coefficients were calculated from the steady-state penetration portions. The flux rates of p-toluidine decreased as the pH value in the donor solution increased. On the other hand, the flux rates of aminopyrine were constant at any pH value. The permeability coefficients of each drug increased as the pH value in the donor solution increased. The partition coefficients (octanol/buffer) of each drug were dependent on the molecular fraction of un-ionized species. From these results, it is suggested that ionized species of p-toluidine transports through shed snake skin, but the ionized species of aminopyrine does not.

Algorithms↗
PubMed1990

Aminopyrine breath test in alcoholic cirrhosis.

Aminopyrine breath test was performed in 91 consecutive alcoholic cirrhotic patients in order to evaluate its clinical value in this group of patients. As compared with routine liver biochemical tests, aminopyrine breath test was found to be altered most frequently (93.5% of cases). A one-year follow-up was obtained in 69 patients. The one-year mortality rate was only 11% for values of aminopyrine breath test greater than or equal to 2%, whereas it reached 53.5 for results inferior to 2%. The prognostic value of the test was not, however, different from that of the Child-Turcotte classification.

Adult↗
PubMed1994

Determination of aminopyrine, dipyrone and its metabolites in urine by high-performance liquid chromatography.

A readily applicable and accurate isocratic high-performance liquid chromatography method for the detection of aminopyrine, dipyrone and its metabolites in urine is described. Parent drugs and four metabolites were chloroform-extracted from 1 ml of urine after addition of the internal standard isopropylaminoantipyrine and alkalinization. The organic phase was evaporated to dryness, and the residue was reconstituted in the mobile phase, which was injected onto a Spherisorb ODS 5 microns particle-size column (250 x 4.6 mm) using as mobile phase water, methanol, triethylamine, and acetic acid. The column eluent was monitored by ultraviolet absorption at 254 nm. Excellent linearity (r > 0.99) was obtained in the range 1-150 micrograms/ml urine, either for parent drugs and metabolites. This method offers a sensitive assay for aminopyrine, dipyrone (widely consumed in some countries) and its metabolites. After oral administration and collection of 24-h urine, this method allows the in vivo study of aminopyrine metabolism, which reflects liver function.

Adult↗