Simulation of hypogravitation under the conditions of cold exposure and their influence on the epithelium of the mucous membrane of the trachea of rats

Aim. To study the effect of hypothermia and hypogravity on the morphofunctional state of the mucous membrane of the trachea.

Materials and methods. The conditions of hypogravity were modeled in a clinostat for modeling hypogravity (Patent RU183861U1). The study was conducted on 30 male rats, 8-10 weeks old with a body weight of 150300 g. All animals were divided into 3 groups (the control one including intact rats; the experimental one with rats of orthostatic hanging for 30 days and the experimental one with orthostatic hanging for 30 days against the background of cold (-15°C) exposure in a climate chamber. Oscillatory activity of cilia was recorded using a computer system. To evaluate the cilia activity, the frequency of cilia beating by cilia per second of time (Hz) was recorded as well as histological analysis of tracheal tissues.

Results. It was found out that a combination of two stress factors, which include orthostatic hanging and prolonged exposure to low temperatures, significantly changes the morphological and functional structure of the tracheal mucosa compared with the intact group of animals and the group of orthostatic hanging. Long-term action of cold and orthostatic hanging was accompanied by a decrease in the height of the cilia of the ciliated epithelium and tracheal epithelium, accompanied by a significant decrease in cilia vibrations.

Conclusion. The combined effect of the orthostatic hanging and prolonged exposure to low temperatures leads to morphological and functional disturbance of the mucosal epithelium, which in the future will require appropriate correction.

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