Excitatory neurotransmitters
Neurotransmitters that increase the likelihood of a neuron firing an action potential.
Inhibitory neurotransmitters
Neurotransmitters that decrease the likelihood of a neuron firing an action potential.
Major excitatory neurotransmitters
Epinephrine and norepinephrine.
Major inhibitory neurotransmitters
Serotonin and gamma-aminobutyric acid (GABA).
Dual-function neurotransmitters
Acetylcholine and dopamine.
Modulatory neurotransmitters
Also known as neuromodulators, affecting a larger number of neurons simultaneously.
Gamma-aminobutyric acid (GABA)
Acts as the body's main inhibitory chemical messenger.
Glutamate
Plays a role in cognitive functions and can cause excitotoxicity in excessive amounts.
Oxytocin
Hormone and neurotransmitter involved in social recognition, bonding, and sexual reproduction.
Endorphins
Neurotransmitters inhibiting pain signals and promoting euphoria, naturally produced in response to pain.
Ex. Exercising
Epinephrine
Also known as adrenaline, serving as a hormone and neurotransmitter in the body.
Norepinephrine
Plays a role in alertness and the fight or flight response, with levels highest during stress.
Dopamine
Coordinates body movements, involved in reward, motivation, and addiction.
Serotonin
Regulates mood, sleep, anxiety, sexuality, and appetite, targeted by SSRIs for various mental health conditions.
Adenosine
Acts as a neuromodulator, suppressing arousal and improving sleep.
Adenosine triphosphate (ATP)
Functions as a neurotransmitter in the nervous systems, implicated in pain and neurodegenerative disorders.
Nitric oxide
Affects smooth muscles, relaxing them to increase blood flow.
Acetylcholine
Found in both central and peripheral nervous systems, primarily associated with motor neurons, influencing muscle movements, memory, and learning.
Neurotransmitter dysfunction
Imbalance in neurotransmitter levels can lead to various adverse effects on the body and mental health conditions.
Agonists
Increase the effects of specific neurotransmitters.
Antagonists
Block the effects of neurotransmission.
Neuro-acting drugs
Categorized based on direct or indirect effects on neurotransmission.