Experimental study on the effect of bile, and bile and hydrochloric acid mixture on the esophageal mucosa

Introduction: The investigation of duodena gastro esophageal reflux ( DGER) implies both clinical and experimental studies. Within the context of the literature, our study aimed to produce esophageal lesions by the development of an experimental model reproducing the characteristics of DGER and to analyze their microscopic pattern. Material and Methods: The material consisted in three groups of white Wistar rats. Group I ( control group) included physiologic saline gavaged rats. Group II received by the esophageal probe bovine bile pH 7, and group III 0.5% bovine bile at pH 4, to which we added hydrochloric acid 0.1 N. The rats were sacrificed in the 21st day of the experiment. The esophagus was sectioned obliquely and longitudinally, maintaining the lumen and marking the upper and lower extremities. The esophageal fragments were routinely processed for light microscopy pathology exam, in HE staining. Results: The pathologic aspects suggested that the effect of bile and bile and hydrochloric acid mixture on the esophageal epithelium interferes with the normal keratinization process, with consequent onset of hyperkeratinization. Moreover, epithelial atrophy was present in the group II on restricted areas and in the group III on extended territories. Discussion: The alterations in the keratinization process suggest the possibility of initiation in time of carcinogenic mechanism. The atrophic transformations plead for an evolution towards erosion and ulceration. The study takes into consideration the differences between human and experimental animal esophageal epithelium. Conclusions: Thus, there emerge new perspectives to extrapolate the experimental results into the human biologic context, the morphologic pattern proving the irritant effect of DGER in vivo.