Pathogenetic Features of Restoring of Urinary Reservoir Function, Which Was Replaced by an Ileum Implant (Experimental Study)

Abstract

Bladder cancer accounts for 50–70% of all malignant diseases of genital urinary system and 4% of all oncological diseases. It is well known, that in Ukraine men have such pathology 4 times more often than women and, unfortunately, up to 22% of patients die within the first year after confirmed diagnosis. The basic criteria of treatment effectiveness of the patients with oncological diseases are not only the rate of their survival, but also their quality of life. One of the main types of treatment for muscle-invasive bladder cancer is radical cystectomy with different variants of urinary diversion. The morphological changes in the muscle layer of the neobladder can cause deviations in the regulations of its contractility. This evolution of the smooth muscle wall demonstrates the electrophysiological contractility features of the neobladder compared to the ileum. The objective: to analyze the pathogenetic moments of the smooth muscle contractility regulation of the artificial bladder. Materials and methods. The experimental study on female mini-pigs aged 16–19 months, with weight 30–40 kg, the duration of the study was 12 months. The experimental model of the artificial bladder was performed by cystectomy in animals following by the terminal ileum of the neocyst, its anastomosis with the ureters, urethra under the anesthesia. After the forming of the neobladder the experimental animals had anesthesia with tiopental, and the neocyst and part of the ileum were removed, in one year. The experiments were carried put on the 18 pairs of specimens: isolated strips of the small intestine of mini-pigs and strips of the wall of the artificial bladder. Results. It was determined that spontaneous activity of the ileum and neobladder smooth muscles in 12 months has different indices. During the experiment the spontaneous activities of longitudinal smooth muscles (SM) of the ileum and neobladder were compared. It was determined that the spontaneous contractions of the neobladder SM are significantly different from the strip ileum contraction in control by larger amplitude and the complex shape. Conclusions. The hypertrophic growth of smooth muscles (SM) is a complex dynamic phenomenon that includes not only the structural changes, but also the complex physiological processes, namely aimed at transforming the part of the intestines to perform a new function of the urinary reservoir. The artificial bladder performs the functions of the natural bladder, there by making the life easier for a patient. The study of smooth muscle contractive activity regulation mechanisms under the influence of nervous and humoral systems will allow to expand the methods of its correction.