Exploratory Activity of Rats in the Acute Period of Mild Blast-Induced Traumatic Brain Injury

Abstract

The relevance of this work is related to the widespread use of explosive devices in military conflicts. More common and "invisible" is mild blast-induced brain injury. This can manifest through anxiety, emotional dysregulation, and spatial memory impairments. However, significant variability exists in modeling blast-induced traumatic brain injury and spatial memory assessment methods. This study aimed to investigate the exploratory activity of rats during the acute phase of mild blast-induced traumatic brain injury modelled by using a newly developed device.
 The study carried out on 18 sexually mature male Wistar rats weighing 220-270 g. The selected rats were divided into three groups: an experimental group (n=6), animals were modeled with blast-induced trauma by generating an air shock wave with an overpressure of 26.4±3.6 kPa, sham group (n=6), animals were subjected only to inhalation anesthesia with halothane and fixed in a horizontal position, and an intact group (n=6). The exploratory activity was recorded by the iPhoneXR camera; the route of movement through the maze of rats from three groups was graphically depicted and visually analyzed, as well as the number of entries into the "false shelters" was counted and the performance of experimental, sham and intact rats was compared. On the 1st day of the post-traumatic period, the experimental rats explored a greater number of "false shelters", by 72% (p<0.01) compared to intact animals and by 65% (p<0.05) compared to control animals. On the 3rd day, this activity was higher by 53% (p<0.05) compared to intact and by 67% (p<0.05) compared to control rats. On day 7, experimental rats explored more, by 86% (p<0.01) compared to intact rats and also by 86% (p<0.01) compared to control animals. The obtained results indicate an increase in the exploratory activity of rats in the acute period of mild blast-induced brain injury.