Effect of formaldehyde on thymus morphogenesis of white rats

Abstract

Objective. The study of morphometric parameters of thymus of immature white rats exposed to inhalation of formaldehyde. Materials and methods. It was studied the formaldehyde inhalation effects at concentration of 2.766 mg/m³ on the structure of the thymus of white male rats with an initial body weight of 40-50 g. Formaldehyde exposures were carried out for 1 h/day daily for 10, 20, 30, 60 and 90 days. We studied separately the morphogenesis of thymus of rats that after 60 days of exposure to formaldehyde for 30 days were under standard vivarium conditions. Results. It has been established that the inhalation effect of formaldehyde leads to a decrease in the organometric parameters of the thymus gland in comparison with the control. In animals that were exposed to formaldehyde for 10 and 20 days, the average of the cortex area was lower than the control by 8.06% (p <0.05) and 11.48% (p <0.01), respectively. After 30 and 60 days of exposure to formaldehyde, this difference with control data was 13.60% (p <0.02) and 13.98% (p <0.001), respectively. A decrease in the area occupied by the cortex resulted in an increase in the area of the medulla. Conclusion. Inhalation of formaldehyde causes a decrease in the area of the cortex of the thymus, an increase in the number of apoptotic bodies, which is manifested in the “starry sky” pattern. Reducing the severity of changes in the thymus of animals that were removed from the experiment 30 days after exposure to formaldehyde indicates that the changes in the thymus are reversible.