preganglionic fibre
Quick Summary
A preganglionic fiber is an axon that originates in the central nervous system (brainstem or spinal cord) and extends to an autonomic ganglion. These fibers are part of the autonomic nervous system, which regulates involuntary bodily functions like heart rate, digestion, and gland secretion.12
In the parasympathetic nervous system, preganglionic neurons are found in the brainstem or sacral spinal cord. Their axons travel to ganglia located near or within target organs, such as the eyes, heart, or digestive tract. These neurons, along with postganglionic neurons, use acetylcholine as a neurotransmitter.34
The sympathetic nervous system also utilizes preganglionic neurons, which originate in the thoracic and lumbar spinal cord. Their axons synapse in paravertebral or prevertebral ganglia, which are generally located further from the target organs compared to parasympathetic ganglia.2
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human nervous systemThe peripheral nervous systemPreganglionic fibers originating from the brain or spinal cord enter motor ganglia, where they synapse on multipolar cell bodies. These postganglionic cells, in turn, send their processes to visceral structures.
Read MorePreganglionic fibers originating from the brain or spinal cord enter motor ganglia, where they synapse on multipolar cell bodies. These postganglionic cells, in turn, send their processes to visceral structures.
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nerve…in a sympathetic ganglion (the preganglionic fibre), the second (the postganglionic fibre) arising in the ganglion and passing to the organ innervated.
Read More…in a sympathetic ganglion (the preganglionic fibre), the second (the postganglionic fibre) arising in the ganglion and passing to the organ innervated.
Read More