Abstrakt: |
Mast cells are abundant in the intestine and release H, an autocoid which has been implicated in the etiology of necrotizing intestinal disorders. We investigated the effect of histamine receptor blockers on reperfusion injury in the rabbit intestine. 25 rabbits underwent laparotomy under anesthesia. 8 were pre-treated with IV Cimetidine (C), an H2blocker, (25 mg/kg), 9 with IV diphenhydramine (D), an H2blocker, (5 mg/kg), and 8 received no drug. In each, 4 intestinal loops were prepared: 2 loops were rendered ischemic for 5 mins., the other 2 loops serving as nonischemic controls. The animals were sacrificed 4 hrs. after surgery. All Intestinal loops were fixed and examined histologically by a single pathologist unaware of group assignment. Histological changes were graded.Irrespective of ischemia, the intestinal loops in rabbits pre-treated with C and D demonstrated mucosal necrosis when compared to untreated animals (p<0.001, chi-square). These data suggest that blockade of both H1and H2receptor sites potentiated mucosal injury. |