neuromodulator

biochemistry

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July 1, 2026

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Neuromodulators are substances that work alongside neurotransmitters to influence the excitatory or inhibitory responses of receptors in the nervous system. Unlike neurotransmitters, they don't directly activate ion-channel receptors. It can be challenging to distinguish between transmitters and modulators when many substances are present.12

Neurotransmitters are chemical agents released by neurons to transmit nerve impulses across a synapse to neighboring neurons, muscle cells, or gland cells. They are synthesized by neurons and stored in vesicles at the axon's terminal end. When a nerve impulse arrives, these vesicles release neurotransmitters into the synaptic cleft, where they bind to receptors on the next cell, altering its ion permeability and potentially triggering an electrical impulse. Examples include acetylcholine, dopamine, and norepinephrine.34

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hypothalamus
Hypothalamic regulation of hormone secretion
…as neurotransmitters but also as neuromodulators. As neuromodulators, they do not act directly as neurotransmitters but rather increase or decrease the action of neurotransmitters. Well-known examples are the opioids (e.g., enkephalins), so named because they are endogenous (produced in the human body) peptides (short chains of amino acids) with a…
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…as neurotransmitters but also as neuromodulators. As neuromodulators, they do not act directly as neurotransmitters but rather increase or decrease the action of neurotransmitters. Well-known examples are the opioids (e.g., enkephalins), so named because they are endogenous (produced in the human body) peptides (short chains of amino acids) with a…
Read More

nervous system
Neurotransmitters and neuromodulators
…transmitter substances but also of neuromodulators. Neuromodulators are substances that do not directly activate ion-channel receptors but that, acting together with neurotransmitters, enhance the excitatory or inhibitory responses of the receptors. It is often impossible to determine, in the presence of many substances, which are transmitters and which are modulators.…
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…transmitter substances but also of neuromodulators. Neuromodulators are substances that do not directly activate ion-channel receptors but that, acting together with neurotransmitters, enhance the excitatory or inhibitory responses of the receptors. It is often impossible to determine, in the presence of many substances, which are transmitters and which are modulators.…
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zombie-ant fungus
Zombie behavior modification and mechanisms
…fungus secretes a number of neuromodulatory agents, particularly guanobutyric acid and sphingosine, near both the central and peripheral nervous systems of its host. The fungus also contains a slew of unusual bacteria-like toxins, which may impair the chemical signals that allow the ant to communicate with other members of its…
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…fungus secretes a number of neuromodulatory agents, particularly guanobutyric acid and sphingosine, near both the central and peripheral nervous systems of its host. The fungus also contains a slew of unusual bacteria-like toxins, which may impair the chemical signals that allow the ant to communicate with other members of its…
Read More