Abstract:

Objective To explore the optimal concentration of NaOH solution that can cause the esophageal stenosis and establish the animal model of esophageal stenosis in lower thorax of rabbits. Methods Twenty adult rabbits were randomly divided into the experiment groups (group A, B, and C) and control group. Each group consisted of 5 rabbits. Under fluoroscopy monitoring, 1.5 mL of 1%, 4%, and 10% NaOH solution and normal saline were given to the experiment groups (group A, B, and C) and control group by catheters, respectively. The mental status and appetite of rabbits were observed. The body mass was weighted once a week and the esophagogram was conducted every 2 weeks. Rabbits were sacrificed after 4 weeks and the esophagus in lower thorax was excised for the pathological examination. Results No obvious esophageal stenosis was found in rabbits of group A. All rabbits of group C died within 72 h after experiment. Seconddegree burn injury and esophageal stenosis were observed in rabbits of group B. Morphological manifestations indicated that stricture index of the esophagus increased. Immunohistochemical observations showed mucous layer defects and accumulation of submucosal collagen. The differences of the hydroxyproline level, histopathologic score, and body mass of group B were significantly different to the control group and group A (P<0.01). Conclusion The rabbit model of benign esophageal stricture can be established successfully by burning the esophagus with 4% NaOH solution under the fluoroscopy monitoring.

Key words: esophageal stenosis, two catheters, NaOH solution, optimal concentration