RESEARCH ON THE INJURY OF "Z" STENT ON ESOPHAGUS IN EXPERIMENTAL DOGS / 解放军医学杂志

ABSTRACT

To observe the changes in mucosal blood flow and permeability after esophageal "Z"stenting, 12 adult healthy dogs were divided into two groups, and an esophageal stent was placed in each dog. Mucosal blood flow was measured with Dopplar blood flowmeter. Two hours after stenting PEG400 was instilled into the esophagus continuously under a constant pressure for two hours in the first group. The amount of PEG400 in the stented tissue was measured with gas liquid chromatography.In the second group the same experiment was carried out 24 hours after stenting. The mucosal structure was examined with electron microscope after stenting. It was found that the mucosal blood flow decreased evidently, and the amount of PEG400 was much greater in tissue after being stented as compared with that in normal esophagus. Electron microscopy revealed that the number of desmosome of epithelium decreased, and it was disrupted significantly after stenting. The interval epithelial cells were enlarged, basement membrane was damaged. Stenting might lead to evident decrease of esophageal mucosal blood flow, which significantly impaired the junction of epithelial cells and mucosal structure, and the permeability for PEG400 was increased significantly. All these findings demonstrate that stenting might impair the esophageal mucosa.