Study of morphological transformation and features of vascular blood flow of the wall of the small and large intestine in the simulation of ischemia in the experiment

Abstract

Introduction. Ischemia of the small and large intestine of various degree was simulated in 45 sexually mature male rats of the Wistar line weighing 150-200 g on the basis of the Department of Experimental Medicine with vivarium at Privolzhsky Research Medical University. Аim. To present in an experiment the effect of different degrees of occlusive ischemia on the morphological transformation of the intestinal wall and the level of changes in blood flow.Materials and methods. The anesthetized animals underwent a median laparotomy with subsequent differentiation of the intestinal divisions: the jejunal section was selected in the small intestine, the ascending section was selected in the large intestine. With the help of a nylon thread (5-0), the blood supplying arcades of these zones were ligated and further exposed for 40, 60 and 120 minutes. During the indicated periods of ischemia, the average rate of blood supply in capillary microvessels located at a depth of 0.5-1.0 mm was estimated in relative units on 1.0 mm2-area (LACC-02, NPP Lazma, Russia). After the assessment of vascular blood flow was completed, ischemic intestinal areas were sampled for morphological examination. The study results were processed using Excel application and STADIA statistical package. Results. In the course of study, the authors registered clear relationships between blood flow parameters in different parts of the intestine and the duration of ischemia. Local trophic disturbance was combined with a transformation in the histoarchitectonics of the intestinal wall. It is noted that adaptive-regenerative mechanisms provide tissue stress reduction in 120 min. due to compensatory mechanisms of blood supply contributing to the restoration of the "villus-crypt" system of the mucous membrane.Conclusion. Thus, in case of local ischemia in the small and large intestine, the tissue structure is restored due to adaptive mechanisms of blood supply, this preserves the viability and functionality of the intestinal wall.