Effects of naloxone in intestinal shock in the rat

The contribution of endogenous opioid peptides to the development of circulatory derangement in severe shock was studied using naloxone. A standardized intestinal shock was induced in rats by applying a pressure of 120 cm water on the mesenteric vessels for 60 min. The rats were then given either saline or naloxone. Mean arterial blood pressure improved and a less severe acidosis resulted in naloxone-treated animals compared to saline-treated. No differences were found in hematocrit, the degree of small intestinal mucosal lesions, or survival rates after 7 days comparing naloxone and saline treatment. Survival time increased after naloxone but not after saline treatment. The results support the hypothesis that endogenous opioid peptides contribute to cardiovascular collapse in intestinal shock.