Morphological Characteristics of the Thyroid Gland of Adult Rats with the Reproduction of Moderate Chronic Hyperthermia and the Administration of Inosine

The negative impact of high temperature accompanies the person in the process of work. Overheating causes long-term structural and functional changes in the body, which contribute to the development of destructive processes. On this background, there were no studies of the response of the altered thyroid gland to the use of anabolic medicamentous agents restoring possible changes in the intraorganic metabolism and in particular inosine. The purpose of the study was to determine the morphometric characteristics of the thyroid gland under the influence of prolonged overheating with the combined use of inosine. Material and methods. The study was conducted on 60 linear laboratory adult white Wistar male rats with an initial mass of 180-230 g (10-12 weeks old). Exogenous hyperthermia was created using a thermal chamber. Group I consisted of control rats that were kept in a heat chamber for 5 hours at 21° C daily for 60 days, group II included animals exposed to chronic moderate hyperthermia (42.0-43.1° C) with inosine combined. Hyperthermia was modeled from 8 am to 1 pm (5 hours daily) for 60 days. Pharmacological correction of changes resulting from exposure to elevated ambient temperature to extreme was carried out using a synthetic drug of the metabolic type of the action of purine nucleoside - inosine (0.2g coated tablets) produced by Borschagovsky Chemical Pharmaceutical Plant. Results and discussion. Inosine was administered intragastrically (through a stomach tube) 1 time per day 1 hour before the rats were placed in the chamber for 60 days. After 60-day hyperthemia sessions on days 1, 7, 15, 30 and 60, the rehabilitation of animals was removed from the experiment by decapitation under ether anesthesia. Thus, the studied morphometric parameters of adult rats such as: an increase in the diameter and area of the follicles, an increase in the area of the colloid. Decrease in height and area of thyroid epithelium, increase in the number of thyrocytes in the follicle. An increase in the INK and a decrease in the FKI, a decrease in the radius and area of the nuclei indicate a decrease in the function of the thyroid gland developed under the influence of moderate chronic hyperthermia with the use of inosine in comparison with these indicators in intact animals during all periods of observation. The maximum decrease falls on the initial periods of observation (1 and 7 days), and by 30 and 60 days of rehabilitation, the decrease is insignificant. Conclusions. Thus, the morphometric indices of sexually mature rats developed under the influence of chronic middle-hyperthermia combined with the introduction of inosine on 1, 7, and 15 days indicate a slight decrease in the functional activity of the thyroid gland compared with intact animals, indicating that the function is restored to 30 and 60 days body.