The Effect of Experimental Gastric Dilatation-Volvulus on the Adenosine Triphosphate Content and Cellular Permeability of the Canine Gastric and Jejunal Mucosa

Abstract

This study was designed to characterize changes in the content of adenosine triphosphate (ATP) and cellular permeability of gastric and jejunal mucosa during gastric dilatation-volvulus (GDV). Our hypothesis stated that experimental GDV would result in a decrease in ATP content and cellular integrity of the gastric and intestinal mucosa that may improve after decompression and derotation of the stomach. Fifteen medium-to-large mixed-breed male dogs were randomly divided into three groups: GDV dogs, Ischemia dogs and Control dogs. All dogs were maintained on gas anesthesia for 210 minutes. The GDV dogs had a GDV for 120 minutes with a 90-minute period of decompression, gastric derotation and reperfusion equaling 210 minutes. The Ischemia dogs had a GDV maintained for 210 minutes. The Control dogs had no gastric manipulation. Tissue samples were taken in all dogs from the fundus, pylorus and jejunum at 0 (baseline), 120 and 210 minutes. Quantification of mucosal ATP (ìg/ml) was accomplished using high performance liquid chromatography (HPLC). Mucosal cellular permeability was evaluated using Ussing chambers by measuring conductance over 180 minutes (ÄGt). A significant decrease in ATP below baseline occurred in the fundic mucosa in the Ischemia dogs. A significant decrease in ATP was seen in the jejunual mucosa in GDV and Ischemia dogs between baseline and 120 minutes; however, a return to baseline levels was seen in GDV dogs from 120 to 210 minutes. No significant change in Gt from baseline was seen in the fundic mucosa in any dogs. A significant increase in Gt was seen in the jejunal mucosa in the GDV and Ischemia dogs between baseline and 120 minutes. The increase in Gt continued from 120 to 210 minutes and was most profound in the GDV dogs. The decrease in fundic ATP did not coincide with permeability changes. Interestingly, the jejunum showed profound changes in both ATP concentration and permeability. It is the authors’ opinion that with the decrease in ATP concentration and loss of cellular integrity in the jejunal mucosa, the jejunum could be implicated as a contributor to complications associated with GDV.