preganglionic neuron
Quick Summary
A preganglionic neuron is a type of neuron in the autonomic nervous system. It originates in the central nervous system, either the brainstem or spinal cord, and its axon extends to an autonomic ganglion. In these ganglia, the preganglionic neuron synapses with a postganglionic neuron, which then innervates target tissues like smooth muscle, cardiac muscle, or glands. The autonomic nervous system, which includes the sympathetic and parasympathetic divisions, regulates involuntary bodily functions to maintain homeostasis. Preganglionic neurons are crucial for transmitting signals from the central nervous system to the peripheral nervous system to control these functions.1234
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human nervous systemThe autonomic nervous systemThe first set, called preganglionic neurons, originates in the brainstem or the spinal cord, and the second set, called ganglion cells or postganglionic neurons, lies outside the central nervous system in collections of nerve cells called autonomic ganglia. Parasympathetic ganglia tend to lie close to or within the organs…
Read MoreThe first set, called preganglionic neurons, originates in the brainstem or the spinal cord, and the second set, called ganglion cells or postganglionic neurons, lies outside the central nervous system in collections of nerve cells called autonomic ganglia. Parasympathetic ganglia tend to lie close to or within the organs…
Read More- human nervous systemNeurotransmitters and receptors
…the sympathetic system appears simple: preganglionic neurons use acetylcholine as a neurotransmitter, whereas most postganglionic neurons utilize norepinephrine (noradrenaline)—with the major exception that postganglionic neurons innervating sweat glands use acetylcholine. On closer inspection, however, neurotransmission is seen to be more complex, because multiple chemicals are released,
Read More…the sympathetic system appears simple: preganglionic neurons use acetylcholine as a neurotransmitter, whereas most postganglionic neurons utilize norepinephrine (noradrenaline)—with the major exception that postganglionic neurons innervating sweat glands use acetylcholine. On closer inspection, however, neurotransmission is seen to be more complex, because multiple chemicals are released,
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