To compare the general condition, HE staining and protein expression of 5%NaOH solution and 5%HCl solution in rabbit erosive esophagitis stricture model.

Nine New Zealand white rabbits of clean grade, male or female, aged 5 months, weighing (2.5 ± 0.5) kg, labeled 1~9, were purchased and randomly divided into groups A, B and C, with 3 rabbits in each group. Group A was modeled with 5%NaOH solution, Group B with 5%HCl solution, and Group C with 0.9% physiological saline as the control group. After successful inhalation anesthesia, an independently closed esophageal burn area was constructed by double-lumen balloon method, and 5%NaOH solution, 5%HCl solution, and 0.9% normal saline (total 1.0 mL) were injected into the isolated site of groups A, B, and C, respectively, and maintained for 30 seconds, then groups A and B were washed with normal saline several times. The body weight, food characteristics and dysphagia of the model rabbits were observed at 1 day, 3 days, 5 days and 1 week after model establishment, and HE staining and protein expression [collagen Ⅰ, smooth muscle actin (a-smooth muscle actin, a-SMA)] in the esophageal stricture segment were detected.

Nine New Zealand white rabbits were successfully modeled. In group A, body weight gradually decreased 1~9 days after modeling, body weight maintained the weight on the 9th day in the later stage, food intake decreased, and food could not be eaten after the 6th day. In group B, body weight was reduced, food traits were mainly solid, and they could not eat after the 9th day. In group C, body weight was normal, food traits were solid, and swallowing was normal. (1) Gross view: gross morphology showed luminal narrowing and local color deepening.(2) HE staining: In group A, extensive necrosis and destruction of myometrial structure were observed in the mucosa and submucosa, and inflammatory cell infiltration mainly eosinophil cells and lymphocytes were observed in the stroma. In group B, the squamous epithelium structure was intact and a few collagen fibers proliferated.In group C, the squamous epithelium structure was intact. (3) Protein expression: Collagen fiber deposition and smooth muscle actin expression were observed in group A.

5%NaOH solution has a corrosive effect on the three layers of esophageal structure in rabbits with corrosive esophagitis stricture, while 5%HCl solution only injures the mucosal layer, which may provide protection for the deep layer of esophagus.