Integration of intestinal structure, function, and microvascular regulation.

Without an increase in blood flow to provide additional oxygen, intestinal absorption of nutrients cannot proceed. Studies of the intestinal microvascular structure and distribution of resistance indicated that most of the microvascular regulation must occur outside the mucosal tissues. This requires a communication system from the mucosa to resistance vessels unlike that of any other organ. The various mechanisms involved and their communication from mucosal to arteriolar cells has required an integrated study of intestinal structure, physiology, and microvascular regulation. The results of this analysis using diverse approaches have revealed some of the major physical and cellular mechanisms that couple intestinal absorption and microvascular function.