[Liver microsome monooxygenase activity in rats under the effects of organochlorine and organophosphorus pesticides and different nutrition background]. / Aktivnost' monooksigenaz mikrosom pecheni krys pri vozdeistvii smesi khlor- i fosfororganicheskikh pestitsidov na fone razlichnogo pitaniia.

The influence of acute and chronic intoxication with a mixture of lindane and trichlorometaphos-3 on monooxygenases of rat liver was studied in rats insufficiently provided with lysine and vitamins A, C and E. It has been found that in the presence of poly-nutrient insufficiency monooxygenase induction develops more rapidly and to a greater extent than in the presence of balanced nutrition. Chronic intoxication with the pesticide mixture leads to monooxygenase system induction under both regimens of nutrition. It has been noted that in most cases monooxygenase induction during intoxication in the presence of poly-nutrient insufficiency is attended by an increase of the relative mass of the liver. A possible role of this phenomenon has been considered.

[Metabolism of the pesticide trichlorometaphos-3 and its effect on the monooxygenase system depending upon the supply of lysine, methionine, threonine and vitamins A, B and C]. / Metabolizatsiia pestitsida trikhlormetafosa-3 i vliianie ego na monooksigenaznuiu sistemu v zavisimosti ot obespechennosti lizinom, metioninom, treoninom, vitaminami A, C i E.

Metabolism of organophosphate pesticide trichlorometaphos-3 and its effect on liver monooxygenase system were studied in male rats of WAG strain, maintained on a diet deficient in lysine, methionine, threonine and vitamins A, C, E. Long-term deficiency of these essential nutrients led to inhibition of monooxygenase induction in acute intoxication with pesticide (150 mg/kg) and to restriction of the induction in chronic intoxication (3 mg/kg) within 3 and 6 months. As a result of the intoxication highly toxic intermediate 2,4,5-trichlorophenol was accumulated in liver tissue of the animals kept on the disbalanced diet. The data obtained suggest that the increased accumulation of 2,4,5-trichlorophenol in liver tissue, as a result of intoxication with trichlorometaphos-3, potentiated the effect of essential nutrients deficiency on stimulation of the monooxygenase system.

[Effect of acute and chronic lindane poisoning on the function of the liver microsome mono-oxygenase system in rats maintained on a diet deficient in lysine, methionine, threonine and vitamins A, C and E]. / Vliianie ostrogo i khronicheskogo otravleniia lindanom na funktsiiu monooksigenaz mikrosom pecheni krys na fone nedostatochnogo postupleniia v organizm lizina, metionina, treonina i vitaminov A, C i E.

Polynutrient deficiency in essential amino acids and vitamins A, C and E led to induction of liver tissue microsomal monooxygenase system in male rats of WAG strain within first 2 hrs and to inhibition of the induction within the subsequent hours after a single dose administration of a pesticide lindane (18 mg/kg) as compared with control animals maintained on a normal diet. The deficiency in essential nutrients caused also a delay in the monooxygenase induction in rats treated daily within 3 months with lindane at a dose of 0.9 mg per kg of body mass. No distinct nutritionally-dependent differences in the rate of the monooxygenase induction were observed after 6 months of the chronic treatment with the pesticide. Activity of monooxygenases in nutritionally-deprived and lindane-treated rats was decreased as compared with the similarly treated rats which were maintained on a normal diet. The induction of monooxygenases in experimental rats was accompanied by an increase in relative mass of liver tissue. The increase in liver tissue mass appears to occur as an adaptive response to the polynutrient deficiency and the effect of xenobiotics in order to maintain the enzymatic system at an adequate functional level.

[Effect of lysine, threonine, methionine and vitamin A, C and E deficiency on the liver microsome enzyme system responsible for metabolizing foreign compounds in the rat]. / Vliianie nedostatka lizina, treonina, metionina i vitaminov A, C, E na fermentnuiu sistemu mikrosom pecheni krys, otvetstvennuiu za metabolizatsiiu chuzherodnykh soedinenii.

It has been demonstrated that the deficiency of 3 essential amino acids (lysine, threonine and methionine) combined with polyhypovitaminosis A, C and E for 2 months leads to a decrease in the para-hydroxylase and N-demethylase activity in rat liver microsomes. The content of cytochromes P-450 and b5 was also reduced as compared to that in animals given balanced nutrition. However, in such a polynutrient deficiency, the activity of microsomal enzymes was induced by phenobarbital to a greater degree than in balanced nutrition. It is suggested that in polynutrient deficiency, the lacking essential factors mobilized from other organs and tissues are involved in the process of induction of microsomal enzymes.