Morphological Characteristics of the Results of Experimental Modeling of Septic Peritonitis

SUMMARY: Experimental studies devoted to the study of the mechanisms of the pathogenesis of acute peritonitis and the development of new methods of medical and surgical treatment are becoming increasingly relevant. Today, experimental medicine knows many different ways to modeling septic peritonitis and eliminate it, but the role of the local immune system is underestimated, whereas it takes a direct part in inflammation. The objective of our work to study morphological features of results of experimental modeling of septic peritonitis in white rats. The study included 15 sexually mature white male rats weighing 276.75±6.56 grams. A simulation of septic peritonitis was performed by perforating the upper part of the cecum with four punctures with a G16 injection needle. As a result of the experiment, after examination of the peritoneal cavity, all 15 animals were diagnosed with omentum tamponade of perforated damage to the caecum. In 11 cases, the perforated wall of the caecum was covered by the greater omentum (73.34 %), and in the other 4 animals, tamponade was performed by one of the epididymal omentum (26.66 %). The initial stage of tamponade with the greater or epididymal omentums of a perforated caecum begins on the first day of the experiment and consists of tight interstitial consolidation between them, as well as in the invasion of blood vessels from the omentum side to the focus of infection, which ensure the delivery of the appropriate immunocompetent cells. As a result of this process, intensive lymphoid infiltrates are formed in this area, as well as the growth of adipose tissue, which isolates the inflammatory focus from the peritoneal cavity with a thick layer.

Las investigaciones experimentales dedicadas al estudio de los mecanismos de patogénesis de la peritonitis aguda y el desarrollo de nuevos métodos de tratamiento médico y quirúrgico son cada vez más relevantes. Hoy en día, la medicina experimental conoce muchas formas diferentes de modelar la peritonitis séptica y eliminarla, pero se subestima el papel del sistema inmunológico local, mientras que él participa directamente en la inflamación. El objetivo de nuestro trabajo fue estudiar las características morfológicas de los resultados del modelado experimental de peritonitis séptica en ratas blancas. El estudio incluyó 15 ratas macho blancas, sexualmente maduras que pesaban 276,75 ± 6,56 gramos. Se realizó una simulación de peritonitis séptica perforando la parte superior del ciego con cuatro punciones con una aguja de inyección G16. Como resultado del experimento, después del examen de la cavidad peritoneal, a los 15 animales se les diagnosticó taponamiento del omento o lesión perforada del ciego. En 11 casos, la pared perforada del ciego fue recubierta por el omento mayor (73,34 %), y en los otros 4 animales el taponamiento se realizó por uno de los epidídimos (26,66 %). La etapa inicial del taponamiento con omento mayor o epidídimo de un ciego perforado comienza el primer día del experimento y consiste en una estrecha consolidación intersticial entre ellos, así como en la invasión de los vasos sanguíneos desde el lado del omento hasta el foco de infección, que aseguran la entrega de las células inmunocompetentes apropiadas. Como resultado de este proceso, se forman intensos infiltrados linfoides en esta zona, así como el crecimiento de tejido adiposo, que aísla el foco inflamatorio de la cavidad peritoneal con una gruesa capa.

The effection of heat stress on cell immunology in rats / 重庆医学

Objective To investigate the effect of heat stress on the expression of Toll-like receptor 4 (TLR4) and peripheral blood T regulatory cells (Treg) in splenic cells of rats.Methods Senventy-two SD rats were divided into 20 ℃ control group and 37 ℃ group.Each group was divided into non stimulation,bacterial lipopolysaccharide (LPS) stimulation and concanavin A (Con-A) stimulation subgroup.Each subgroup had 1,12,48 h and 168 h observation points,and flow cytometry was used to determine the level of TLR4 and Treg.Results The TLR4+ immunocompetent cells in the spleen was decreased from 1 h to 168 h in every subgroup of the 37 ℃ group compared to the 20 ℃ control group (P＜0.05).The level of CD4+CD25+ Treg in the peripheral blood in rats from 1 to 48 h was significantly decreased (P＜0.05) and slightly increased at 168 h in LPS stimulation subgroup in the 37 ℃ group compared to the 20 ℃ control group.The level of CD4+ CD25+ Foxp3+ Treg in the peripheral blood in rats at 12 h were significantly increased in non-stimulation and concanavalin A (Con-A) stimulation subgroups in the 37 ℃group,and were significantly decreased at 168 h in every subgroup of the 37 ℃ group compared with 20 ℃ control group (P＜0.05).The level of CD8+CD25+ Treg in the peripheral blood in rats was significantly increased at 1 h and 168 h in the 37 ℃ hot and humid group in the every subgroup whencompared with the 20 ℃ control group (P＜0.05).The level of CD8+ CD25+Foxp3+ Treg in the peripheral blood in rats was significantly decreased at 1 h and 48 h in the every subgroup,and was significantly increased at 12 h and 168 h in the non-stimulation and LPS stimulation subgroups in the 37 ℃ group compared to the 20 ℃ control group (P＜0.05).Conclusion High temperature and damp heat can destroy the innate immunity and alter the functional state of adaptive immunity in rats.