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 co ntrol rats were uninjured in group A, and the others were injured rats in g roups 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 g roups as described by Gehanno. One milliliter of 10% sodium hydroxide solut ion in groups B, C, and D and 0.9% saline solution in group A were instille d 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 cau stic injury in group B, 48 hours after in group C, and 72 hours after in gr oup D. In group A, studied uninjured segments were removed for biochemical investigation. Tissue malondialdehyde (MDA) and glutathione (GSH) levels we re 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 le vels in the same esophageal tissues were significantly lower in groups C an d D than in groups A and B (P < .05). Conclusion: The reactive oxygen radicals may be play an important role in e arly phase of caustic esophageal burns by increasing the tissue damage. Cop yright (C) 1999 by W.B. Saunders Company.