In the autonomic nervous system, fibers from the CNS to the ganglion are known as preganglionic fibers. This article or section is in need of attention from an expert on the subject. ... A diagram showing the CNS: 1. ... Template:Game Autonomic nervous system innervation, showing the sympathetic and parasympathetic (craniosacral) systems, in red and blue, respectively Autonomic ganglia are clusters of neuronal cell bodies and their dendrites and are essentially a junction between autonomic nerves originating from the central nervous system and autonomic nerves innervating their target organs...
All preganglionic fibers, whether they are in the sympathetic division or in the parasympathetic division, are cholinergic (that is, these fibers uses acetylcholine as their neurotransmitter). Grays FIG. 838– The right sympathetic chain and its connections with the thoracic, abdominal, and pelvic plexuses. ... It has been suggested that Parasympatholytic be merged into this article or section. ... A synapse is cholinergic if it uses acetylcholine as its neurotransmitter. ... The chemical compound acetylcholine, often abbreviated as ACh, was the first neurotransmitter to be identified. ... Neurotransmitters are chemicals that are used to relay, amplify and modulate electrical signals between a neuron and another cell. ...
Sympathetic preganglionic fibers tend to be shorter than parasympathetic preganglionic fibers because sympathetic ganglia are often closer to the spinal cord than are the parasympathetic ganglia.
The first neuron is the preganglionic neuron, and its cell body is located somewhere in the CNS (brain or lateral horn of the spinal cord).
The preganglionic axon forms a synapse with the cell body of the postganglionic neuron, found in an autonomic ganglion outside the CNS.
Preganglionic axons extend almost all the way to the target effector, where they synapse with the postganglionic neurons, which are found very close to or within the target organ
Preganglionic sympathetic fibers also travel in the ventral root of the spinal nerve for a short time before they enter the sympathetic trunk through the white rami communicans.
Preganglionic parasympathetic fibers leave the spinal nerve as the pelvic splanchnic nerves (to be learned later) but never reenter it to be distributed to the periphery.
Preganglionic neuron and fiber; cell body and preganglionic fiber originate in the brain and the spinal cord.
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