COMPARATIVE CHARACTERISTICS OF CHANGES IN HEMO - AND LYMPHOMICROCIRCULATORY VESSELS OF ILEUM ACCUMULATED LYMPHOID NODES OF RATS IN THE CASE OF APPLICATION OF INFUSION SOLUTIONS IN EXPERIMENTAL BURN DISEASE
Authors: Dzevulska I.V. , Matkivska R.M. , Sinitska A.M. , Prysiazhnjuk L.V. , Yanchyshyn A.Y. 
Published: July 2021

Relevance. Thermal burns of the skin cause the development of burns, the main factor of which is endogenous intoxication. The infusion of detoxification solutions is a mandatory component of the treatment of burns, as it corrects its course and prevents the development of certain stages and complications. According to the stage of the burn disease and the different direction of its links in its pathogenesis, infusion therapy should not only restore water-electrolyte balance and detoxify the body, but also contribute to the normalization and stabilization of vital (including immune) body functions.

Objective: study of changes in the vessels of the hemo- and lymphomicrocirculatory system of Peyer's patches in burnt rats at the stages of burn disease, under conditions of intravenous infusion of isotonic sodium chloride solution and combined colloidal-hyperosmolar solutions (lactoprotein and sorbitolum).

Materials and methods. The experiment was performed on 72 white rats. Experimental animals were divided into 4 groups (18 animals in each group). I, II, III - rats with skin burn trauma, which received a separate infusion of isotonic sodium chloride (I), lactoprotein with sorbitol (II) and hecoton (III), at a dose of 10 ml / kg. IV - intact animals (control group).

Simulation of burn disease was performed by inflicting burn injury by applying to the lateral surfaces of the body of animals four copper plates, which were previously kept for 6 minutes in water with a constant temperature of 100 ° C. Histological and electron microscopic examination were performed. Light microscopy was used.

Results. Intravenous administration of the applied infusion solutions caused various phase changes of the hemo- and lymphomicrocirculatory tract of Peyer's patches of the ileum of burnt rats, depending on the applied solution. In the case of infusion of burnt rats with 0.9% sodium chloride solution, the negative effects of burn disease were exacerbated, which were manifested by damage to the vascular wall of the hemo- and lymphocapillary channels, resulting in plasma and lymph seepage through the affected areas into the perivascular space. This process was accompanied by a violation of the rheological properties of blood, the formation of edema. The established "membrane-plastic effect" of lactoprotein with sorbitol revealed clear organ-specific features, which had manifestations of penetration through the damaged wall of microvascular electron-dense impregnations, which contributed to a significant thickening of the basement membrane in the wall of the blood capillary formation and its gradual formation of rounded membranous structure. This structure of variable electron density not only strengthened the vascular wall, but also served as a closure, helping to close the vascular lumen at the site of largest damage. The difference between the perinodal lymphatic capillaries in burnt rats infused with lactoprotein and sorbitol is characterized by the phenomenon of "overflow" of the lymphocapillary channel with cells in different functional states. In the case of infusion of hecoton solution, the effect of "overflow" of the lymphocapillary channel was not observed, which indicates adequate implementation of the immune function of immunocompetent cells.

Conclusions. Intravenous infusion of colloid-hyperosmolar solutions causes various changes in the hemo- and lymphomicrocirculatory tract of Peyer's patches. Infusion of a  0.9% sodium chloride solution leads to a deepening of the negative consequences of burn disease, which manifests itself in the form of damage to the vascular wall of the hemo- and lymphocapillary channels. Infusion of solutions of lactoprotein with sorbitol and hecoton helps to preserve the vascular wall of the nodular lymphatic capillaries. When a solution of lactoprotein with sorbitol is applied around the damaged vessels of blood capillaries and venules, annular membrane formations are formed, which promote selective recirculation of structurally intact lymphocytes.