Newborn intestinal circulation - Physiology and pathophysiology

One of the most important differences between the circulatory physiology of the newborn intestine and adult intestine is that the basal vascular resistance across newborn intestine significantly decreases in the first several days after birth, secondary to a marked increase in the constitutive and stimulated production of nitric oxide by the vascular endothelium. This resistance reduction causes the nominal rate of intestinal blood flow, and hence oxygen delivery, to be increased during early newborn life. The importance of endothelium-derived nitric oxide in regulation of the newborn intestinal circulation renders it susceptible to ischemia during periods of endothelial cell dysfunction.