EVALUATION OF BENZALKONIUM CHLORIDE CHEMONEUROLYTIC PROXIMAL GASTRIC-VAGOTOMY

Background: Transmucosal chemoneurolytic injection of benzalkonium chl oride (BAC) has previously been shown to duplicate operative proximal gastric vagotomy (PGV) in controlling gastric acid secretion. In this study, BAC was evaluated as to efficacious dose, methods of delivery, and systemic toxicities. Methods: Sham celiotomy, operative PGV contro ls, transmucosal injections through a gastrotomy, and transserosal inj ections of BAC (saline controls, 0.625, 1.25, 2.5, 5.0, 10 mg BAC/kg b ody wt) were administered to Sprague-Dawley rats. After 3 months the r ats underwent Congo red testing (CRT), horseradish peroxidase (HRP) ne uronal staining, and necropsy. The color density change of the gastric mucosa from basic to acidic demonstrated by the CRT at the time of ne cropsy was used to calculate the residual anatomic acid-secreting area . Prior to necropsy, subserosal HRP injections into the anterior and p osterior stomach walls assayed vagal neuronal viability via retrograde axonal flow. Results were compared by an ANOVA. Results: The results demonstrated that 1.25-10 mg/kg transmucosal BAC replicated the result s of operative PGV; 2.5 mg/kg was found to be the most effective dose. All injection groups including saline controls demonstrated similar d iminished vagal retrograde axonal flow by HRP testing consistent with local BAC chemoneurolytic effects. No systemic toxic symptoms were obs erved after tail vein intravenous BAC 1.25, 2.5, and 5.0 mg/kg. Conclu sions: These efficacy studies have demonstrated BAC's potential utilit y in the performance of endoscopic transmucosal chemoneurolytic PGV.