【Animal modeling】-Gastroesophageal reflux model

  Gastroesophageal reflux refers to the reflux of stomach contents, including bile salts and pancreatic enzymes that flow into the stomach from the duodenum, into the esophagus. It can be divided into two types: physiological reflux and pathological reflux. Pathological reflux is due to the dysfunction of the lower esophageal sphincter and the abnormal tissue structure related to its function, so that the pressure of the lower esophageal sphincter (LES) is low, causing a series of clinical symptoms and complications, that is, gastroesophageal reflux Flow sickness. Gastroesophageal reflux disease is a dysmotility disease of the digestive tract caused by a variety of factors. It is the result of a decline in the defense mechanism against reflux and the attack of reflux on the esophageal mucosa. Animal model studies are very helpful to explain the pathogenesis of this disease. The researchers used newborn piglets to make animal models of gastroesophageal reflux caused by different factors. Through X-ray barium meal fluoroscopy, gastroesophageal pressure measurement, esophageal pH monitoring, and stomach Intestinal hormone determination and other detection methods, systematic research on the main factors of gastroesophageal reflux formation, pathophysiology, pathological anatomy evolution and reversibility of gastroesophageal reflux, provide valuable theories for the prevention and treatment of gastroesophageal reflux.

  At present, piglets 7-8 days after birth are mostly used to prepare models. There are two methods for preparing models. The first is to induce esophagitis through exogenous acids; the second is to cause esophagitis through its own gastrointestinal reflux. The methods are mostly pylorus and proximal small intestine ligation, cardia muscle incision and other surgical methods. The specific steps are as follows: make a reflux esophagitis model of miniature pigs through abdominal surgery, use a midline epigastric incision from the xiphoid process to the umbilicus into the abdomen, pull the liver upwards and the stomach downwards after opening the abdomen, exposing the gastroesophageal junction , With a sharp blade at the gastroesophageal junction longitudinally incise the muscle layer 3cm. There is no need to suture after the muscular layer is incised, but care should be taken when incising the muscular layer to avoid cutting the mucosal layer. After the incision, the mucosal layer can be seen to bulge out. If the mucosal layer is cut accidentally, it should be done in time repair. The animals were given liquid food for 3 days after the operation. If the operation is successful, reflux esophagitis may appear a few days later. However, each of the above methods has limitations. Model animals cannot continue to be fed and observed, and cannot fully understand the entire process of pathophysiological evolution. But it is certain that the gastric peristalsis is weakened, emptying obstacles, intragastric pressure rises, the volume increases, and the abdominal esophagus is shortened, which destroys the coordination function of the normal peristalsis of the stomach, pylorus and duodenum, and causes the stomach and esophagus to react. An important factor in flow.