Assessment of changes in the main homeostasis indicators in mammals after hyperthermic exposure

. The occupation of firefighters is characterized by the impact of both hazardous fire factors and a complex of harmful and dangerous characteristics of various natures, often exceeding the expected values. High air temperature is typical for almost all types of fire and is one of the main adverse physical factors affecting the body of firefighters. Experimental models on animals are of leading importance in studying extreme fire factors, including hyperthermic exposure. Material and methods. The study was carried out on 124 outbred white male rats of 3 months of age weighing 250-300 g, divided randomly into two groups. The first group (62 rats) was subjected to a single hyperthermic load. The second group (62 rats) was subjected to daily hyperthermic load during 14 days. The study of the leading indicators of the acid-base state and water-electrolyte balance, biochemical and clinical blood tests, cellular and humoral immunity was carried out before and after hyperthermic exposure. Results. The obtained data indicate high ambient temperatures cause changes in homeostasis indices in laboratory animals. At the same time, there are alterations in the indicators of water-electrolyte balance, acid-base state, clinical and biochemical blood tests and the immune system. Conclusion. An experimental model of extreme heat exposure on animals showed the emergence and persistence of changes in the leading indicators of homeostasis. In the group of single hyperthermia, these parameters were restored to the background levels in a day. In the group of multiple hyperthermia, they remained altered.