preganglionowy

Preganglionic refers to a neuron in the autonomic nervous system whose cell body is located within the central nervous system (brain or spinal cord) and whose axon extends outward to synapse with a postganglionic neuron in an autonomic ganglion. These neurons are part of the efferent pathway of the autonomic nervous system, transmitting signals from the central nervous system to peripheral effector organs.

In the sympathetic division of the autonomic nervous system, preganglionic neurons originate in the thoracic and lumbar segments of the spinal cord. Their axons are generally short and myelinated, terminating in ganglia located in the sympathetic chain or in collateral ganglia closer to the target organs. In contrast, preganglionic neurons of the parasympathetic division originate in the brainstem and sacral segments of the spinal cord. Their axons are typically long and myelinated, extending to ganglia located near or within the walls of the target organs themselves.

Preganglionic neurons utilize acetylcholine as their primary neurotransmitter at the synapse with postganglionic neurons. This neurotransmitter binds to nicotinic acetylcholine receptors on the postganglionic neuron, causing depolarization and initiating an action potential that travels to the effector organ. The activity of preganglionic neurons is modulated by input from the central nervous system, allowing for regulation of involuntary bodily functions such as heart rate, digestion, and gland secretion.