neurotransmitter

(noun)

Any substance, such as acetylcholine or dopamine, responsible for sending nerve signals across a synapse between two neurons.

Related Terms

Examples of neurotransmitter in the following topics:

  • Neurotransmitters

    • Neurotransmitters match up with receptors like a key in a lock.
    • A neurotransmitter binds to its receptor and will not bind to receptors for other neurotransmitters, making the binding a specific chemical event.
    • The cholinergic system is a neurotransmitter system of its own, and is based on the neurotransmitter acetylcholine (ACh).
    • Another class of neurotransmitter is the biogenic amine, a group of neurotransmitters made enzymatically from amino acids.
    • Dopamine is the best-known neurotransmitter of the catecholamine group.

  • Mechanics of the Action Potential

    • During a chemical reaction, a chemical called a neurotransmitter is released from one cell into another.
    • Synaptic cleft: the small space at the synapse that receives neurotransmitters.
    • The neurotransmitter diffuses within the cleft.
    • The binding of neurotransmitter causes the receptor molecule to be activated in some way.
    • Several types of activation are possible, depending on what kind of neurotransmitter was released.

  • Stages of the Action Potential

    • A neuron affects other neurons by releasing a neurotransmitter that binds to chemical receptors.
    • A neurotransmitter can be thought of as a key, and a receptor as a lock: the key unlocks a certain response in the postsynaptic neuron, communicating a particular signal.
    • However, in order for a presynaptic neuron to release a neurotransmitter to the next neuron in the chain, it must go through a series of changes in electric potential.
    • Reuptake refers to the reabsorption of a neurotransmitter by a presynaptic (sending) neuron after it has performed its function of transmitting a neural impulse.
    • Reuptake is necessary for normal synaptic physiology because it allows for the recycling of neurotransmitters and regulates the neurotransmitter level in the synapse, thereby controlling how long a signal resulting from neurotransmitter release lasts.

  • Etiology of Schizophrenia

    • Research has shown that neurotransmitter activity is significantly related to schizophrenia.
    • Dopamine is not the only neurotransmitter associated with schizophrenia, although it can be argued that it is the most studied.
    • In addition to neurotransmitters, specific neural circuitry in various areas of the brain has been linked to schizophrenia.
    • Disregulation of neurotransmitters in the association cortex may explain why people with schizophrenia are not able to properly sort or filter information.
    • A variety of factors have been associated with schizophrenia, including genetic predisposition, environmental factors, and neurotransmitter imbalances.

  • Depressants

    • Depressants cause the body to relax by increasing the neurotransmitter GABA, which decreases neuronal excitability.
    • On the neural level, most depressants act on the brain by affecting the neurotransmitter gamma-aminobutyric acid (GABA), which is responsible for regulating (specifically, decreasing) neuronal excitability throughout the nervous system.
    • Neurotransmitters are brain chemicals that facilitate communication between brain cells.
    • Benzodiazepines enhance the effect of the neurotransmitter gamma-aminobutyric acid (GABA) at the GABA receptor, resulting in sedative, hypnotic (sleep-inducing), anxiolytic (anti-anxiety), anticonvulsant, and muscle-relaxant properties.

  • Habituation, Sensitization, and Potentiation

    • In neural communication, a neurotransmitter is released from the axon of one neuron, crosses a synapse, and is then picked up by the dendrites of an adjacent neuron.
    • During habituation, fewer neurotransmitters are released at the synapse.
    • In sensitization, however, there are more pre-synaptic neurotransmitters, and the neuron itself is more excitable.
    • This image shows the way two neurons communicate by the release of the neurotransmitter from the axon, across the synapse, and into the dendrite of another neuron.
    • Communication between neurons occurs when the neurotransmitter is released from the axon on one neuron, travels across the synapse, and is taken in by the dendrite on an adjacent neuron.

  • Hallucinogens

    • Deliriants work by inhibiting acetylcholine, a neurotransmitter responsible for cognition and stimulation.
    • PCP (or angel dust), a dissociative, prevents the actions normally caused when a neurotransmitter called glutamate is able to attach to its receptor in the brain.
    • It also disrupts the actions of other neurotransmitters.

  • Stimulants

    • Some stimulants facilitate the activity of certain neurotransmitters, specifically norepinephrine and/or dopamine.
    • Amphetamines (such as ephedrine and methamphetamine) are a group of stimulants that increase the levels of norepinephrine and dopamine in the brain through reuptake inhibition—meaning they block these neurotransmitters from being reabsorbed back into the neural networks.
    • MDMA differs from most stimulants in that its primary pharmacological effect is on the neurotransmitter serotonin rather than dopamine, epinephrine, or norepinephrine.

  • Cognitive Development in Childhood

    • These synapses release neurotransmitters, which are chemical signals that help the brain communicate.
    • These structures are responsible for releasing neurotransmitters, which are chemical signals that help the brain communicate.

  • Obsessive-Compulsive Disorder

    • Studies have implicated about two dozen potential genes that may be involved in OCD; these genes regulate the function of three neurotransmitters: serotonin, dopamine, and glutamate (Pauls, 2010).
    • OCD has been linked to abnormalities with the neurotransmitter serotonin, although this could be either a cause or an effect of OCD.