The role of bile reflux in the development of cold-restraint gastric lesions

The study was designed to test whether or not bile reflux is necessary for the development of gastric mucosal lesions during cold-restraint stress in the rat. 40 male Sprague-Dawley rats were studied. They were randomized into 4 groups. Group 1 underwent sham operations with no cold-restraint stress. Group 2 underwent sham operations. Group 3 underwent pyloric ligation. Group 4 underwent bile duct ligation. Groups 2, 3, and 4 were subjected to cold-restraint stress for 3 hours at 4-6 degrees C in a Bollman cage. After the experimental procedure, the stomachs were removed under ether anesthesia, the severity of lesions was recorded, and blood from the hearts was obtained for hematocrit readings. The mean lesion scores of all groups exposed to cold-restraint stress were similar and much higher than that of the unrestrained sham-operated group (P smaller than 0.001). Also, mean hematocrit readings in all groups exposed to cold-restraint stress were lower than in the control group (P smaller than 0.05). There was a correlation between severity of mucosal lesions and hematocrit reading (rs=0.57, P smaller than 0.001). The results obtained allow the following conclusions: (1) Bile reflux is not necessary for formation of cold-restraint stress lesions in the rat. (2) Hematocrit readings appear to be a useful measure of blood loss secondary to experimental mucosal lesions.