Figure 22.9 • Autonomic Innervation of the Colon – The small intestines and colon are innervated by both sympathetic and parasympathetic nerves. Sympathetic fibers from the spinal cord lead to the celiac, superior mesenteric ganglia, and inferior mesenteric ganglia. Parasympathetic fibers arise from the vagus (innervate through transverse colon) and pelvic (innervate descending colon, sigmoid, and rectum) nerves. Sympathetic stimulation reduces motility and secretions, whereas parasympathetic stimulation increases motility, secretions, and relaxation of the internal anal sphincter.