ДОСЛІДЖЕННЯ СТАНУ ІМУННОЇ СИСТЕМИ ЩУРІВ ПРИ ДІЇ НІТРОБЕНЗОЛУ ТА МЕТИЛТРЕТБУТИЛОВОГО ЕФІРУ В УМОВАХ ХОЛОДОВОГО СТРЕСУ ТА В УМОВАХ ТЕМПЕРАТУРНОГО ОПТИМУМУ

Abstract

The article describes the results of experimental studies aimed at investigating toxic effects of methyl tertbutyl ether [MTBE] and nitrobenzene [NB] according to the criteria of changes in the immune system status of laboratory animals in conditions of cold stress and in conditions of temperature optimum. The research was carried out in the conditions of a subacute experiment (during one month of experiment) on laboratory animals (adult WAG male rats). The NB or MTBE were injected into the stomach at a dosage 1/10 LD50 (70 mg/kg of NB and 500 mg/kg MTBE) thirty times, the experimental animals were kept in two different temperature conditions during four hours five times per week. The animals were divided into 4 groups, six animals in each group. The animals of the first group were subjected to NB or MTBE at an air temperature of 252C (normal ambient temperature). The animals of the second group served as a control group for the first one. The animals of the third group were subjected to NB or MTBE in combination with the lowered air temperature of 4±2℃. The animals of the fourth group were only subjected to the effect of the reduced temperature of 4±20℃, that is, they were a control group for the ones of the third group. The analysis of the results of the experimental data about the features of the immunotoxic action of NB and MTBE under conditions of cold stress indicates the tension of the immune system of the laboratory animals, which is manifested by progressive lymphopenia and a decrease in the phagocytic activity of neutrophils in absorption of foreign agents, especially in the end-period. The immunotoxic effect of NB and MTBE under conditions of temperature optimum indicates a temporary immune system tension, namely leukocytosis and leukopenia at the stage only after 5 and 15 priming. At the end of the priming period, shifts in the immune system's performance under the effect of NB and MTBE under temperature optimum conditions were not observed, which may indicate a positive adaptability of laboratory animals to the action of chemical factors (NB and MTBE) under such temperature conditions. The combined effect of NB and MTBE on the body at the level of their effective concentrations and low temperature causes a detrimental effect on the adaptability of the body. Thus, these chemical compounds at the stage of physiological adaptation, that is before the formation of the pathological process, complicate the formation of specific and nonspecific reactions responsible for the adaptation of the organism to the effect of another factor in the production or environment – a low air temperature. The latter, in turn, creates an additional load on biochemical detoxification systems, leads to their imbalance and changes in the rate of biotransformation of the chemical agent and the speed of development of the toxic process.