postganglionic fibre

A postganglionic fiber is a nerve fiber that extends from a ganglion, which is a cluster of nerve cell bodies, to an effector organ. These fibers are part of the autonomic nervous system, which regulates involuntary bodily functions like heart rate and digestion.12

The autonomic nervous system has two main divisions: the sympathetic and parasympathetic systems. In both systems, preganglionic neurons originate in the central nervous system (brain or spinal cord) and synapse with postganglionic neurons within autonomic ganglia. The postganglionic fibers then carry the nerve impulse to target tissues such as smooth muscle, cardiac muscle, or glands.2

For example, in the sympathetic nervous system, postganglionic fibers innervate various organs, including blood vessels, sweat glands, and muscles of the skin. In the parasympathetic nervous system, postganglionic fibers are often embedded within the walls of the organs they control, such as the heart or gastrointestinal tract.34