Distribution of blood flow in the intestine with hypertonic glucose in the lumen

The effects of luminal placement of 50 percent glucose solution on distribution of blood flow within the jejunal wall were studied with radioactive microspheres. Two types of spheres, 15 +/- 5 mu in diameter, were used. One was labeled with cerium- 141 (Ce- 141) and the other with strontium-85 (Sr-85). They were injected sequentially to test for reproducibility of the results. These two types of spheres gave similar results qualitatively and quantitatively. Luminal placement of 50 percent glucose increased total blood flow to the jejunal wall but the increase occurred mainly in the mucosal layer. The flow to the submucosa or muscularis-serosa was not altered. This increased mucosal flow was attenuated by prior exposure of the mucosa to a local anesthetic, dibucaine. It is suggested that the increased intestinal blood flow that occurs in the experimental dumping syndrome is confined to the mucosa of the intestine and is mediated by mechanisms that can be inhibited by exposing the mucosa to a local anesthetic.