Peripheral autonomic pathways
Peripheral autonomic pathways innervate most tissues of the body. Autonomic final motor neurons lie outside the central nervous system in ganglia containing up to a million neurons. Neurons in sympathetic, cranial parasympathetic and pelvic ganglia are under central control via preganglionic neurons. In addition to motor neurons, enteric ganglia contain intrinsic primary afferent neurons and interneurons, generally without direct central input. Autonomic neurons utilize diverse co-transmitters in pathway-specific combinations. Each target tissue is controlled by specific sets of autonomic neurons, closely coordinated with relevant neuroendocrine and somatic motor activity.