BIOCHEMICAL INDICATORS OF CONNECTIVE TISSUE IN RAT PERIODONTIUM IN LOCAL GUM DAMAGE UNDER LIPOPOLISACHARIDE-INDUCED SYSTEMIC INFLAMMATORY RESPONSE

Objectives: To assess the biochemical indicators of the connective tissue of rat periodontium (collagen, proteoglycans, glycoproteins) in local gum damage associated with lipopolysaccharide-induced systemic inflammatory response (SIR). Material and methods: The experiment involving 40 white Wistar rats was designed to evaluate the concentration of products of collagenolysis (free hydroxyproline), and the depolymerization of proteoglycans (glycosaminoglycans, GAG) and sialoglycoproteins (N-acetylneuraminic acid, NANA) in soft tissues of the periodontium (gum, periodontal ligament) and bone tissue of the alveolar process. Results. It has been found out that the application of 5% sodium hydroxide solution onto the gums during SIR induced by intraperitoneal injection of Salmonella typhi lipopolysaccharide (pyrogenal) in a dose of 0.4 μg/kg of weight three times during the 1st week and once a week for the next 7 weeks significantly increases the concentration of free hydroxyproline, GAG and NANA in the soft and bone periodontal tissues, exceeding that of a separate effect produced by alkali and bacterial lipopolysaccharide. Conclusions. The application of a local damaging agent (sodium hydroxide solution) to the gums in amount that in normal conditions does not produce any significant histological effect, can significantly enhance collagenolysis, depolymerization of proteoglycans and sialoglycoproteins in the soft and bone periodontal tissues in the presence of lipopolysaccharide-induced systemic inflammatory response.