Sphincter dysfunction assessment birthing simulation model in rats

• Grant number: 16/17608-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2016
• End date: November 30, 2017
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Flávio Henrique Ferreira Galvão
• Grantee: Bruno Camargo Rocha Paim de Araujo
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Fecal incontinence is a condition that greatly impairs the quality of life of patients and involves high expenses with sophisticated and inefficient treatments. Among the causes for this condition, it highlights traumas that reach the anal region and multiple births. A major obstacle to developing therapies is the lack of scientific models that explain how different mechanisms of injury affect the activity of sphincters. Recently, we have developed a model of sphincter injury simulating five deliveries. Thus, the objective of this project is to assess how the sphincter functional characteristics are affected after each of the five deliveries simulations. Male Wistar rats weighing between 200 and 250 grams will be used. After general anesthesia, the animals will be divided into four groups. Group Control- Animals subjected to anal introduction of 7cm of a Foley catheter and removed soon after. Group I- Animals undergoing Anal 7cm introduction of a Foley catheter, balloon inflation with five ml of distilled water and an episode balloon removal slowly. Group II animals subjected to seven cm Anal introduction of a Foley catheter, balloon inflation with five ml of distilled water and three episodes of slow bubble removal. Group III- animals subjected to seven cm Anal introduction of a Foley catheter, balloon inflation with five ml of distilled water and five episodes of removing the flask slowly. All animals will have their sphincter activity evaluated by means of a manometric specialized apparatus (Dynamed®: DUAL® system). This evaluation will be done before and two hours after the procedure. The animals will be sacrificed after the procedure and the pelvic floor will be removed en bloc and processed with hematoxylin-eosin for histopathological analysis of the anal sphincter. The manometry results will be compared between groups by Student's t test and the severity of the histological lesions by Chi square test. (AU)