LOCOMOTOR ACTIVITY OF RATS WITH BLAST-INDUCED TRAUMATIC BRAIN INJURY IN A COMPLEX MAZE

Abstract

Aim – to investigate the peculiarities of rats with blast-induced brain injury movement in the complex maze.Material and methods. The study was carried out on 15 sexually mature Wistar rats. All animals were randomly divided into 3 groups: experimental group (n=5), which was anesthetized and exposed to an air shock wave with an overpressure of 26-36 kPa; sham group (n=5), which was only anesthetized, and intact group (n=5). The study of locomotor activity was performed using a complex maze for 5 consecutive days, starting on the 1st day after the simulation of blast-induced brain injury. The route of rat`s movement through the maze of three groups was graphically depicted and visually analyzed.Results of the study. The complex maze is considered to be complicated due to the presence of a central zone and T-shaped branches to the right and left, ending with feeders. The complication of the situation and task lead to fear with rapid adaptation of healthy rats. However, if the brain functions are impaired, the experimental animal loses its physiological ability to adapt and shows signs of anxiety. The analysis of the images of the movement paths showed that on the 1st day of training, the rats of the experimental group moved more actively, despite the fact that the animals did not yet know that food was waiting for them. They performed monotonous movements and went to the side sectors more often. On 2nd day, the experimental rats were more active and explored the maze more stereotypically than intact animals. On 3rd and 4th days, clear signs of spatial memory impairment in the experimental group were found in terms of lengthening the path to the feeder. On the 5th day, it was found that the experimental rats were still poorly oriented in the maze, with a monotonous examination of the side sectors.Conclusions. Thus, mild blast-induced traumatic brain injury leads to persistent impairment of spatial memory, as well as behavioral disorders in the form of anxiety. The rats of the experimental group demonstrated stereotypical locomotor activity, as evidenced by the examination of the lateral sectors of the complex maze. At the same time, the memory for food reinforcement was well developed and retained.