postganglioariset

Postganglionic refers to a neuron that extends from a ganglion to an effector organ. In the autonomic nervous system, postganglionic neurons are the final efferent pathway to target tissues such as smooth muscle, cardiac muscle, and glands. These neurons are part of a two-neuron chain, with the preganglionic neuron originating in the central nervous system and synapsing with the postganglionic neuron within an autonomic ganglion.

The neurotransmitter released by postganglionic neurons varies depending on the division of the autonomic nervous system. In the sympathetic nervous system, most postganglionic neurons release norepinephrine (noradrenaline), acting on adrenergic receptors. However, those innervating sweat glands release acetylcholine, acting on muscarinic receptors. In the parasympathetic nervous system, all postganglionic neurons release acetylcholine, acting on muscarinic receptors of the effector organs.

The cell bodies of postganglionic neurons are located in autonomic ganglia, which are clusters of nerve cell bodies outside the central nervous system. These ganglia are organized into sympathetic trunks (paravertebral ganglia) and collateral ganglia (prevertebral ganglia) for the sympathetic division, and terminal or intramural ganglia for the parasympathetic division. The axons of postganglionic neurons are typically unmyelinated and are generally shorter than preganglionic axons. Their function is to transmit signals that regulate involuntary bodily functions, thereby influencing heart rate, digestion, respiration, and glandular secretions.