Peritonitis is characterized by high lethality, which indicates the need to elaborate adequate methods of its treatment. Non-surgical methods applied along with the surgery are elaborated after preliminary experimental studies on animals, that requires to choose the relevant model of peritonitis. The article highlights the issues of the peritonitis relevance, the formation of bacterial biofilm and the choice of methods for peritonitis modeling in the experiment.

No abstract

Background. The lack of decrease in lethality with diffuse peritonitis may be due to a result of the incomplete understanding of the mechanisms of its development. The aim of the research was to study the changes in rats with acute experimental peritonitis. Material and methods. The experiments were carried out on male rats (n=74) divided into 2 series and intraperitoneally injected with: series 1 (control) – 0.9% sodium chloride, series 2 (experimental peritonitis, EP) – 15% fecal suspension, 0.6 ml/100 g. In each group the research was performed in half a day (n=6), 1 day (n=6) and 3 days (n=6) after peritonitis modeling along with the assessment of rats lethality (n=19). The signs of intoxication, the reaction of blood and peritoneal leukocytes, the nitrite/nitrates level and parameters of prooxidant-antioxidant status, the degree of damage to vascular endothelium and peritoneum in rats with peritonitis were analyzed. Results. The decrease in motor activity and muscular strength, the development of fever and tachypnea, leukocytosis in the blood and peritoneal fluid with the increase in quantity of neutrophils and macrophages, appearance of metamyelocytes and myelocytes with the decrease in the percentage of peritoneal formazan-positive neutrophils, reduction in lymphocytes quantity and the lack of eosinophils, rise in concentrations of nitrites/nitrates and lipid peroxidation product – malondialdehyde along with the decrease in the level of antioxidant – reduced glutathione, increase in the quantity of circulating endothelial cells in blood and significant changes of the peritoneum structure were revealed in rats with peritonitis. Conclusions. The research of changes in rats with acute experimental peritonitis has revealed the signs of marked intoxication, changes in the leukocyte differential count of blood and peritoneal fluid in type of neutrophilicmacrophageal leukocytosis with a hyperregenerative shift of leukocyte differential count to the left and impaired ability of peritoneal neutrophils to phagocytosis along with lymphopenia and aneosinophilia, the increase in the level of nitrites/nitrates, development of oxidative stress, lesion of vascular endothelium and significant changes of peritoneum structure.

Background:The slow tendency to decrease in mortality in peritonitis may be due to incomplete understanding of its pathogenesis.Objective: To study some indicators of intoxication and leukocyte response in rodent fecal peritonitis. Material and Methods:The experiments were carried out on male rats (n=74), divided into 2 equal series, which were injected intraperitoneally with: 1st series (control) -0,9% sodium chloride, 2nd series (experimental peritonitis, EP) -15 % fecal suspension, 0,6 ml/100 g. Studies were made after half a day (n=6), one day (n=6) and three days (n=6) of EP, lethality of animals also was assessed (n=19). In rats with fecal peritonitis, some indicators of intoxication were studied by assessing of motor activity, muscle strength, respiration rate and rectal temperature, and the reaction of blood and peritoneal leukocytes basing on determining their quantitative composition and phagocytic activity. Results:In rats with EP, a decrease in motor activity and muscle strength, the development of fever and tachypnea along with changes in blood and peritoneal fluid in type of leukocytosis, an increase in content of neutrophils and macrophages, the appearance of metamyelocytes and myelocytes, a decrease in content of peritoneal formazan-positive neutrophils and blood lymphocytes, absence of eosinophils were found. Conclusion:The study of changes in rats with acute experimental peritonitis revealed the development of severe intoxication, neutrophil-macrophage leukocytosis with a hyperregenerative shift to the left and a decrease in the phagocytic activity of neutrophils along with lymphopenia and absence of eosinophils.