Electron microscopic changes in the skin of rats 1, 3, 7, 14, 21 and 30 days after thermal trauma on the background of the introduction for the first 7 days of 0.9% NaCl solution

Abstract

A burn wound occurs as a result of exposure to high-temperature skin or chemicals and is a serious injury with systemic effects. The problem of treatment of thermal trauma is urgent for modern medicine. Despite the fact that the overall mortality rate has dropped significantly in recent years, research about the development of new treatments and technologies for patients with skin burns is extremely important. The aim of the study is to research the features of electron microscopic changes in the skin of rats during the month after burns of II-III degree against the background of the introduction of the first 7 days of 0.9% NaCl solution. Studies were performed on 180 laboratory white rats-males weighing 155-160 g. In the course of the experiment, the animals were divided into 2 groups: 1 – rats without thermal injury, which were infused with 0.9% NaCl solution at a dose of 10 ml/kg; group 2 – rats which infused 0.9% NaCl solution at a dose of 10 ml/kg for 7 days after skin burns. Burning skin damage was caused by applying to the lateral surfaces of the trunk of rats for 10 seconds four copper plates, heated in water at a constant temperature of 100 C. The total area of skin lesion in rats was 21-23%. Shaving of the lateral surfaces of rats’ trunk, catheterization of veins, staging of skin burns, and decapitation of animals (after 1, 3, 7, 14, 21 and 30 days) were performed under intravenous propofol anesthesia (calculated at 60 mg/kg body weight). Preparations for electron microscopic examination were prepared according to the standard procedure. The data obtained were studied using a PEM-125K electron microscope. Electron microscopic studies of the skin of animals after thermal trauma under the conditions of application of 0.9% NaCl solution have found that in the early stages of the experiment – the stage of shock and early toxemia (1, 3, 7 days) compensatory and adaptive changes of its structural components are combined with signs of destructive disorders. In the epitheliocytes of the epidermis of the affected area of the skin is the destruction of nuclei and cytoplasm. Vascular disorders in the dermis are combined with changes in fibroblasts, an intercellular substance of fibrous connective tissue. In the late stages of the experiment – the stages of late toxemia and septicotoxemia (14, 21 and 30 days), there is a further development and deepening of destructive-dystrophic changes of all structural components of the affected skin, they become irreversible. The processes of granulation tissue formation, its transformation into connective tissue, as well as marginal epithelialization are slow. This morphological condition of the burn wound indicates the need for the use of corrective drugs to reduce destructive changes and the activation of regenerative processes in the area of skin lesions.