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L F Panchenko

Publications and source records attributed to L F Panchenko.

At least 37 records · Page 2Linked to original sources
PubMed1988

[The role of aldehyde dehydrogenases in the malonic dialdehyde metabolism in the rat liver].

The enzymes catalyzing the NAD-dependent oxidation of malonic dialdehyde (MDA) were isolated from rat liver extracts. Upon 5'-AMP-Sepharose chromatography MDA dehydrogenase was separated into two isoforms, I and II. Isoform I was eluted from the affinity carrier with a 0.1 M phosphate buffer pH 8.0. This isoform had a broad substrate specificity towards aliphatic and aromatic aldehydes. Kinetic studies showed that short- and medium-chain aliphatic aldehydes (C2-C6) were characterized by the lowest Km values and the highest Vmax values. The Km' values for MDA and acetaldehyde were 2.8 microM and 0.69 microM, respectively. Isoform II was eluted with a 0.1 M phosphate buffer pH 8.0 containing 0.5 mM NAD, was the most active with medium- and long-chain aliphatic aldehydes (C6-C11) and had Km values for MDA and acetaldehyde equal to 37 microM and 52 microM, respectively. Isoform I was much more sensitive towards disulfiram inhibition than isoform II. Both isoforms had an identical molecular mass (93 kD) upon gel filtration. It is concluded that MDA dehydrogenase isoform I is identical to mitochondrial aldehyde dehydrogenase having a low Km for acetaldehyde, whereas isoform II may be localized in liver cytosol. The role of aldehyde dehydrogenases in the metabolism of aldehydes derived from lipid peroxidation is discussed.

Aldehyde Dehydrogenase↗
PubMed1987

On the role of microsomal aldehyde dehydrogenase in metabolism of aldehydic products of lipid peroxidation.

To elucidate a possible role of membrane-bound aldehyde dehydrogenase in the detoxication of aldehydic products of lipid peroxidation, the substrate specificity of the highly purified microsomal enzyme was investigated. The aldehyde dehydrogenase was active with different aliphatic aldehydes including 4-hydroxyalkenals, but did not react with malonic dialdehyde. When Fe/ADP-ascorbate-induced lipid peroxidation of arachidonic acid was carried out in an in vitro system, the formation of products which react with microsomal aldehyde dehydrogenase was observed parallel with malonic dialdehyde accumulation.

Aldehyde Dehydrogenase↗
PubMed1987

Effect of clofibrate treatment on glutathione content and the activity of the enzymes related to peroxide metabolism in rat liver and heart.

Clofibrate treatment was shown to increase the content of reduced glutathione in rat liver and kidney, but did not alter the glutathione level in heart, brain, spleen and small intestine. Clofibrate did not affect the activity of superoxide dismutase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase in rat liver and heart. The drug decreased the activity of glutathione-S-transferase in the cytosolic fraction of liver homogenate. Glutathione-S-transferase activity in small intestine was also reduced. The administration of clofibrate decreased the content of polypeptides with mol. wt of 22,000 and 24,000 (possible monomers of glutathione-S-transferase) in the cytosolic fraction of liver cells.

Animals↗
PubMed1987

[Alpha interferon interaction with opiate receptors in the rat brain].

The preferential interactions of alpha-interferon (alpha-IFN) with delta and mu opiate receptors were studied. alpha-IFN (specific antiviral activity 2 X 10(3) U/mg protein) was shown to inhibit in the competitive manner 3H-naloxone and 3H-D-ala2, D-leu5-enkephalin (3H-DADL) specific binding to opiate receptor subpopulations. alpha-IFN was much more effective in decreasing 3H-DADL than 3H-naloxone binding in opiate receptors: K1 values averaged 160 +/- 30 and 1150 +/- 80 U/ml, respectively. IFN effective concentrations inhibiting 50% of 3H-naloxone opiate receptor binding in the absence or presence of 100 mmol/l NaCl were similar, and the "sodium shift" value was equal to 1. The independence of alpha-IFN activity of the presence of NA+ cations suggests the antagonist character of alpha-IFN interaction with opiate receptors. Thus, alpha-IFN employed appears to be an alpha-selective ligand displaying the in vitro properties of "pure" morphine antagonists.

Animals↗
PubMed1987

[Effect of ethanol and the catalase inhibitor aminotriazole on lipid peroxidation in the rat myocardium].

The influence of chronic alcohol consumption and catalase inhibitor aminotriazole administration on the level of nonenzymatic lipid peroxidation has been studied in the rat myocardium. It was demonstrated that combined as well as separate treatment with ethanol or aminotriazole elevated the levels of chemiluminescence and enhanced the rate of accumulation of thiobarbituric acid-reactive products in the nuclei-free and total particulate fraction of the rat heart homogenate. The most pronounced effect was noted during combined application of ethanol and aminotriazole. The induction of chemiluminescence by ethanol was prevented by addition of natural (vitamin E, reduced glutathione) or artificial (dibunol) antioxidants into the incubation media. A putative role of the myocardial catalase-containing micro-peroxisomes in stimulation of the intracellular lipid peroxidation is discussed.

Amitrole↗
PubMed1986

[Activation of peroxisomal acyl-CoA oxidase and lipid peroxidation in the rat myocardium as affected by prolonged administration of ethanol].

The influence of chronic alcoholic intoxication on the activity of peroxisomal acyl-CoA oxidase and antioxidative defensive enzymes (catalase, glutathione reductase, glutathione-S-transferase, superoxide dismutase, glucose-6-phosphate dehydrogenase) was studied in the rat myocardium. The parameters of lipid peroxidation in cardiomyocytes (the level of spontaneous chemiluminescence, accumulation of thiobarbituric acid-reactive material), as well as reduced glutathione content were also examined. The data obtained suggest that ethanol-induced activation of lipid peroxidation in the myocardium may be due to the elevation of hydrogen peroxide-generating activity of peroxisomes.

Acyl-CoA Oxidase↗
PubMed1985

Intraparticulate localization and some properties of a clofibrate-induced peroxisomal aldehyde dehydrogenase from rat liver.

A study was made of the effect of chronic administration of the hypolipidemic drug clofibrate on the activity and intracellular localization of rat liver aldehyde dehydrogenase. The enzyme was assayed using several aliphatic and aromatic aldehydes. Clofibrate treatment caused a 1.5 to 2.3-fold increase in the liver specific aldehyde dehydrogenase activity. The induced enzyme has a high Km for acetaldehyde and was found to be located in peroxisomes and microsomes. Clofibrate did not alter the enzyme activity in the cytoplasmic fraction. The total peroxisomal aldehyde dehydrogenase activity increased 3 to 4-fold under the action of clofibrate. Disruption of the purified peroxisomes by the hypotonic treatment or in the alkaline conditions resulted in the release of catalase from the broken organelles, while aldehyde dehydrogenase as well as nucleoid-bound urate oxidase and the peroxisomal membrane marker NADH:cytochrome c reductase remained in the peroxisomal 'ghosts'. At the same time, treatment by Triton X-100 led to solubilization of the membrane-bound NADH:cytochrome c reductase and aldehyde dehydrogenase from intact peroxisomes and their 'ghosts'. These results indicate that aldehyde dehydrogenase is located in the peroxisomal membrane. The peroxisomal aldehyde dehydrogenase is active with different aliphatic and aromatic aldehydes, except for formaldehyde and glyceraldehyde. The enzyme Km values lie in the millimolar range for acetaldehyde, propionaldehyde, benzaldehyde and phenylacetaldehyde and in the micromolar range for nonanal. Both NAD and NADP serve as coenzymes for the enzyme. Aldehyde dehydrogenase was inhibited by disulfiram, N-ethylmaleimide and 5,5'-dithiobis(2-nitrobenzoic)acid. According to its basic kinetic properties peroxisomal aldehyde dehydrogenase seems to be similar to a clofibrate-induced microsomal enzyme. The functional role of both enzymes in the liver cells is discussed.

Aldehyde Dehydrogenase↗
PubMed1985

Subcellular distribution and properties of a clofibrate-induced aldehyde dehydrogenase from rat liver.

The influence of hypolipidemic drug clofibrate on the activity of aldehyde dehydrogenase with different substrates was studied in subcellular fractions of rat liver homogenate. It was shown that under the action of clofibrate the content of the enzyme was increased 2-3-fold in purified peroxisomal fraction as well as in microsomes and mitochondria. No difference was found in the cytoplasmic fraction. Partial purification of clofibrate-induced aldehyde dehydrogenase from microsomes was undertaken. The enzyme is apparently membrane-bound. It has a molecular weight of 187,000 and a subunit size of 47,000, indicating that the molecule is a tetramer. An induced aldehyde dehydrogenase is active with several aliphatic and aromatic aldehydes but not with formaldehyde and glyceraldehyde. The enzyme has Km-values in the millimolar range for acetaldehyde, propionaldehyde, benzaldehyde and phenylacetaldehyde and in the micromolar range for nonanal. Both NAD and NADP serve as coenzymes for the purified aldehyde dehydrogenase. According to substrate specificity, kinetic and molecular properties clofibrate-induced aldehyde dehydrogenase appears to be identical to normal liver microsomal enzyme.

Aldehyde Dehydrogenase↗
PubMed1985

Effect of clofibrate treatment on aconitase activity in rat liver and other tissues.

The activity of both mitochondrial and cytosolic aconitases was significantly increased in the livers of male rats following treatment with the hypolipidemic drug clofibrate. Cycloheximide or puromycin administration to rats inhibited the inducing effect of clofibrate on the enzyme activity. Aconitase activity in small intestine homogenate was also increased by clofibrate. The drug did not affect the enzyme activity in rat kidney, heart and brain.

Aconitate Hydratase↗
PubMed1984

Glucose-6-phosphate dehydrogenase of rat liver peroxisomes.

A study was made of the effect of chronic administration of clofibrate on the activity and intracellular localization of rat liver glucose-6-phosphate dehydrogenase. Clofibrate-activated glucose-6-phosphate dehydrogenase was found to be located in peroxisomes.

Animals↗
PubMed1984

[Effect of transcutaneous transcerebral electrostimulation as electroanesthesia on the beta-endorphin content of the cerebrospinal fluid and blood plasma].

The beta-endorphin content was measured in the cerebrospinal fluid (CSF) and blood plasma of patients before and after 30 minutes of transcutaneous transcerebral electric stimulation in the electric anesthesia mode. The output current was biphasic and rectangular. It was composed of high-frequency pulse trains (peak-to-peak intensity 250-300 mA, frequency 167 kHz) modulated by low frequency (77 Hz). Electrical stimulation resulted in an appreciable increase in the beta-endorphin content in the CSF and blood plasma of patients. The data obtained attest to the intensification of the neuromodulator release to the CSF and blood plasma and to the involvement of the endorphinergic brain systems in the realization of the analgetic effect of transcutaneous transcerebral electric stimulation.

Adult↗
PubMed1984

[Mechanism of action of ethanol on enkephalinase A activity in the rat brain].

The influence of ethanol, its metabolites and some opiates on enkephalinase A activity was studied in rat experiments in vitro after acute and chronic administration of ethanol. It was demonstrated that addition of ethanol to the reaction mixture activated enkephalinase A of the midbrain and hypothalamus of intact rats, the maximal effect being attained at an ethanol concentration of 10(-3) M. Multiple washings with buffer of the ethanol-preincubated membranous fraction of these brain structures in the control rats did not lead to a significant reduction in the activating effect of ethanol on enkephalinase A. No activation was recorded upon the use of an enzymatic preparation of the brain from chronically alcoholized animals. Morphine, naltrexon, beta-carbolines, salsolinol (10(-4) M) and acetaldehyde (10(-8)-10(-2) M) did not activate the enzyme. It is suggested that enkephalinase A activation in rats given ethanol is determined by a direct action of ethanol on the enzyme.

Animals↗
PubMed1984

[Effect of ethanol on the enkephalinergic opioid system of the rat brain].

The effects of ethanol were examined on the main parameters of rat brain enkephalinergic neurotransmission, e.g., enkephalinase A activity, enkephalin content and specific binding of 3H-morphine and 3H-(D-Ala2, D-Leu5)-enkephalin. Administration of ethanol in a single dose led to significant changes in the tested parameters; upon chronic treatment with ethanol these changes were either less pronounced or altogether absent. The stimulating effect of ethanol on the release and utilization of enkephalins was supposed. Evidence in favour of the hypothesis on the functional relationship between the opiate receptors of the delta-type and enkephalinergic neurotransmission was obtained.

Animals↗