| The inferior mesenteric plexus extends along the inferior mesenteric artery. It contains sympathetic fibers only. An inferior mesenteric ganglion is not often seen, and instead preganglionic sympathetic fibers from the intermesenteric plexus synapse on diffuse ganglion cells near the origin of the inferior mesenteric artery, and postsynaptic fibers follow the artery and its branches. No parasympathetic fibers are found in this plexus. Parasympathetics from the pelvic splanchnic nerves innervate the colon from the splenic flexure to the anal canal. These fibers travel through the fusion fascia on the left side of the posterior abdominal wall to reach the colon walls, synapsing there. |  |
