Reactive oxygen radical levels in caustic esophageal burns

Purpose: This study was designed to determine the tissue levels of reactive oxygen radicals in caustic esophageal burns in a rat model. Methods: Forty rats were divided into four groups of 10 animals each,The control rats were uninjured in group A, and the others were injured rats in groups B, C, and D. Through a median laparatomy incision, a 1.5-cm abdominal esophageal segment was isolated and tied with 2-0 chromic sutures in all groups as described by Gehanno. One milliliter of 10% sodium hydroxide solution in groups B, C, and D and 0.9% saline solution in group A were instilled through the isolated segment via a no. 24 cannula for 3 minutes, then the esophagus was rinsed for 1 minute with distilled water. The studied 1.5 cm of the abdominal esophagus was removed from each animal 24 hours after caustic injury in group B, 48 hours after in group C, and 72 hours after in group D. In group A, studied uninjured segments were removed for biochemical investigation. Tissue malondialdehyde (MDA) and glutathione (GSH) levels were determined for each group. Results: The mean MDA levels in esophageal tissue were significantly higher in groups B, C, and D than in group A (P < .05). Moreover, the mean GSH levels in the same esophageal tissues were significantly lower in groups C and D than in groups A and B (P < .05). Conclusion: The reactive oxygen radicals may be play an important role in early phase of caustic esophageal burns by increasing the tissue damage. Copyright (C) 1999 by W.B. Saunders Company.