Thyroid morphogenesis in rats after thiotriazoline correction of two-month exposure to epichlorohydrin in different age periods

Abstract

Background. The purpose of the study is to establish in the experiment morphofunctional changes in the thyroid gland of rats of various ages after the use of thiotriazoline against the background of exposure to epichlorhydrin. Materials and methods. The experimental study was conducted on 360 laboratory white male rats of three age series: 1st - immature; 2nd – sexually mature; 3rd – the period of pronounced senile changes. The animals of each series were divided into 3 groups. The first group consisted of rats who were exposed to inhaled epichlorhydrin – in a chronic mode (5 hours a day, 5 days a week, 60 exposures), in 10 MPC (10 mg/m3). The second group consisted of rats who, against the background of inhaled epichlorhydrin seed, were injected with thiotriazoline intraperitoneally at a dose of 117 mg / kg, in the mode – 1 time a day at 14.00, 5 days a week, N 60. The control group consisted of intact rats. The animals were removed from the experiment 1, 7, 15, 30 and 60 days after the end of the two-month period of experimental exposure. The thyroid gland was examined at the macro-, micro- and ultramicroscopic levels of the organization and the level of hormones in the blood was determined by solid-phase enzyme immunoassay. Results. The absolute mass is less than that of intact rats in the early stages of readaptation – in the 1st series on day 1 by 6.58% (p<0.05) and on day 7 by 9.34% (p< 0.05), in the 2nd series – on day 1 by 8.81% (p<0.05), on day 7 by 9.15% (p< 0.01) and on day 15 by 7.77% (p<0.05), and in the 3rd series – on day 1 by 12.89% (p< 0.01) and on day 7 by 9.38% (p<0.01). The micro- and ultrastructure is similar to that in the control group. The height of thyrocytes is reduced, however, in comparison with the groups (ECG); there is a decrease in the degree of deviations from the control. Conclusion. The use of thiotriazoline in conditions of chronic intoxication of the body with epichlohydrin leads to an increase in body weight gain, a decrease in the percentage of deviations, restoration of the balance between the fractions and an increase in the rate of recovery of thyroid parameters during the period of readaptation and less pronounced violations of hormonal regulation of adaptation processes. A higher efficiency of the use of thiotriazoline was established in rats who received the corrector at an immature age.

Keywords

• rats
• thyroid gland
• epichlorhydrin
• thiotriazoline
• age
• structure