The effect of 2,6-dimethylpyridine N-oxide on cognitive functions and emotional state of rats following ins long-term oral administration

Background. Global anthropogenic environmental pollution, intensification of production, daily physical, emotional and psychogenic stress on humans, as well as the working environment provoke a variety of diseases, fatigue, and cognitive impairment, etc. This may be attributed to a reduced nonspecific resistance of the health system and the development of stressful conditions. Therefore, one of the focal points of preventive toxicology is the development of agents with adaptogenic properties that would prevent the occurrence of harmful effects under the influence of stressors. The aim of the present study was to examine the effect of 2,6-dimethylpyridine N-oxide on cognitive functions and emotional status of rats following its long-term oral administration. Materials and Methods. The plant growth regulator (PGR) Ivin (2,6-dimethylpyridine N-oxide, 99.9%) was chosen for the study. Adaptogen Eleutherococcus was used as a reference agent. The study was conducted on Wistar Hannover rats divided into 2 cohorts. Each cohort included the following groups: 1 – intact animals, 2 – control (distilled water), 3 and 4 – Ivin at doses of 13.0 and 0.013 mg/kg (1/100 and 1/100000 LD50), respectively, 5 – Eleutherococcus at a dose of 50 mg/kg. Exposure period – 28 days, oral route of administration. The state of the central nervous system was assessed by behavioural reactions in the Morris Water Maze and the Elevated Plus Maze. Results. Ivin at doses of 13 and 0.013 mg/kg increased the ability to learn and to form short- and long-term memory in rats, as evidenced by a decrease in the average time of platform location in the Morris Water Maze test. Ivin at a dose of 0.013 mg/kg significantly increased the number of rearings in closed arms of the Elevated Plus Maze, indicating its anxiolytic effect. The anti-anxiety effect of Ivin needs to be confirmed by additional studies in the Open Field and/or Hole-board tests. The effectiveness of Ivin in terms of the studied parameters was similar or exceeded those of the known adaptogen Eleutherococcus.