Biologichni Studii / Studia Biologica

Background. Environmental and human lifestyle pollution with industrial chemicals, intensification of production, a long-lasting physical, emotional, and psychogenic stress lead to the occurrence of a variety of somatic diseases, fatigue, and memory disorders. This may be due to a reduced non-specific resistance and functional reserves of an organism, as well as the development of stressful conditions. Therefore, a current priority in preventive toxicology is the search for synthetic substances with adaptogenic properties that can enhance the immune system’s resistance to adverse effects. In this regard, the task of this study was to investigate the physical activity of rats under the influence of 2,6-dimethylpyridine N-oxide (Ivin) and under conditions of additional chemical load with сhlorpyrifos. The aim of the research was to study the Ivin’s effect on the motor activity and coordination of Wistar Hannover rats and on the resistance of an organism to an additional chemical agent load.
Materials and Methods. 2,6-dimethylpyridine N-oxide, 99.9% (Ivin) was chosen for the study. Adaptogen Eleutherococcus was used as a comparison agent. The study was conducted on 50 male Wistar Hannover rats divided into 5 groups (10 rats per group): 1 – intact animals (not treated male rats), 2 – control animals (trained male rats were treated with distilled water as a vehicle), in groups 3 and 4 rats were treated with Ivin at doses of 13.0 and 0.013 mg/kg (1/100 and 1/100000 LD₅₀), respectively, 5 – male rats were treated with Eleutherococcus (as a positive control) at a dose of 50 mg/kg. The exposure period with oral administration lasted for 28 days. The physical activity of rats was studied using the rotarod test. Following the completion of Ivin treatment, the animals in the same experimental groups were administered chlorpyrifos (CHP) at a single dose of 37.5 mg/kg to evaluate their physical activity under conditions of an additional toxic load.
Results and Сonclusions. It was found that the time spent by rats on a rota­ting cylin­der increased by more than 11 and 10 times after a single exposure to Ivin at
a dose of 13.0 mg/kg and 0.013 mg/kg, respectively. Following 14 and 28 days of exposure to Ivin at a dose of 0.013 mg/kg, the covered distance was increased by 172.7 % and 291.5 %, and the time spent on the rod was increased by 2.5 and 3.5 times, respectively, in comparison with intact animals. Significantly relevant changes in the parameters caused by eleutherococcus were observed after the 28-day exposure. After admini­stration of CHP at a dose of 37.5 mg/kg to intact and control (trained) rats, the time spent on the rod decreased by almost 2 times. In groups of animals that received CHP in combination with Ivin, the riding time of the rats was 27–30 % higher compared to the effect of the combination of eleutherococcus reference drug and CHP.
Thus, Ivin at a 13 mg/kg single exposure, and at a 0.013 mg/kg single and long-term exposure significantly increases the time spent by rats on a rotating rod (rotarod test), which indicates an increase in motor activity, balance, and muscle strength of animals. The efficacy of Ivin was comparable to, or greater than that of the reference drug, eleutherococcus. chlorpyrifos significantly reduces the physical activity of intact and control (physically trained) rats in the rotarod test. Ivin, at the tested doses, dimini­shed the negative effect of chlorpyrifos on the physical performance of rats, indicating an increase of the organism resistance to additional chemical load.