1 The lower esophageal sphincter was destroyed. Lower esophageal sphincter is the most important structure of anti-reflux barrier at the junction of esophagus and stomach, and its main physiological function is to prevent reflux of contents. Therefore, once this part is stimulated by drugs, diet, smoking and other factors, it can affect the function of lower esophageal sphincter and induce reflux esophagitis.

2 esophagus cleans the esophagus with normal function, which can empty and neutralize saliva. When the acid stomach contents are in reflux, almost all the reflux can be emptied by the second peristalsis of esophagus 1 ~ 2 times (10 ~ 15 seconds).

In addition, a small amount of acid in the residual esophageal mucosa can also be neutralized by saliva. But once this cleaning function is destroyed, esophageal reflux will occur.

3 Gastroduodenal Reflux When the tension of pyloric sphincter and the relaxation pressure of lower esophageal sphincter are low, hydrochloric acid and pepsin in gastric juice, cholic acid in duodenal juice, pancreatic juice and lysolecithin can all reflux to esophagus at the same time, eroding esophageal epithelial cells, and pepsin in reflux penetrates into esophageal tissue, causing esophagitis.

4 Esophageal mucosal injury When the esophageal mucosa is damaged to a certain extent, esophagitis may occur even under normal reflux. This is mainly because the proliferation and repair ability of epithelial cells become worse after the esophageal mucosa is damaged, which leads to esophagitis.