Assessment of the combined effects of a complex of physical and chemical factors on physiological parameters, behavioral reactions and accelerated aging in a chronic animal experiment

The study of physiological parameters and behavioral reactions in Wistar rats exposed to prolonged dynamic stressful effects of a complex of physical and chemical factors (at the level of 1.5 MPC) under model conditions is of wide research interest, as it allows us to assess the complex effects of these factors on model organisms, and to identify the presence of changes in relation to the control group that do not exposed to this effect during the 180‑day experiment. Objective: to evaluate the combined effects of physical and chemical factors on physiological parameters, behavioral reactions, and accelerated aging of laboratory animals in a chronic experiment that characterizes the stages of the adaptation process. The object of the study: white laboratory rats of the Wistar line (n=90), grouped into three groups: two experimental ones, kept in conditions of periodic combined exposure to physical (vibration, noise), as well as physical (vibration, noise) and chemical (4‑component mixture of aromatic hydrocarbons) factors at the level of 1.5 MPC, MPC, and one control (intact animals) — in comfortable conditions (normal photoperiodism and temperature +22–24 ° C). The parameters of body weight and temperature and the functional activity of the nervous system were studied using the «Open Field» method. The statistical analysis was carried out using standard Statistica 10.0 application programs with the calculation of the median (Me) and the percentile interval. The probability of differences of 95 % or higher (p<0.05) was considered an acceptable level of reliability of the results. The animals of all groups showed a constant temperature balance and an increase in body weight by day 180 of the experiment, and the body weight gain was higher in the animals of the experimental groups compared with the control. Indicators of motor, emotional and research activity statistically significantly decreased on the 180th day of the experiment in animals of the experimental groups, and grooming significantly decreased in rats in the group of combined physical and chemical exposure starting from the 120th day compared with the control group. The study of the complex periodic influence of physical and chemical factors (1.5 MPC, MPC) on changes in body weight, temperature balance, anxiety, emotional state and cognitive activity in model animals as biological (living) systems contributes to the study of the mechanisms of premature aging and the development of occupational diseases among workers in conditions of occupational hazards.