Neurotransmitters Flashcards
The ______ is the main excitatory neurotransmitter in the brain.
Glutamate
The ______ is the primary inhibitory neurotransmitter in the central nervous system.
GABA
The ______ receptors are ionotropic receptors activated by glutamate and glycine, allowing Na+ and Ca2+ influx.
NMDA
The ______ receptor subtype is responsible for fast excitatory postsynaptic potentials.
AMPA
Metabotropic glutamate receptors (mGluRs) can be classified into groups based on their signaling: Group I is ______, while Group II and III are ______.
excitatory, inhibitory
______ transporters remove glutamate from the synaptic cleft to maintain neurotransmitter balance.
EAAT
The balance between ______ and ______ is crucial for maintaining proper excitation and inhibition in the brain.
Glutamate, GABA
The ______ receptor is a pentameric structure that, when activated, allows Cl- ions to enter the cell, causing inhibition.
GABA-A
The ______ receptor is a G-protein coupled receptor that inhibits Ca2+ channels and activates K+ channels.
GABA-B
Benzodiazepines bind to the ______ receptor to enhance the effects of GABA.
GABA-A
The precursor to dopamine is ______, which crosses the blood-brain barrier.
L-DOPA
Dopamine plays a key role in ______, ______, and ______.
motor control, reward, motivation
The four major dopamine pathways are ______, ______, ______, and ______.
mesolimbic, mesocortical, nigrostriatal, tuberoinfundibular
The ______ pathway is involved in reward and motivation, projecting from the VTA to the nucleus accumbens.
Mesolimbic
Dopamine receptors can be classified into two families: the ______ family (Gs-coupled) and the ______ family (Gi-coupled).
D1, D2
The ______ receptor family includes D1 and D5 receptors, which increase cAMP levels.
D1
The ______ receptor family includes D2, D3, and D4 receptors, which decrease cAMP levels.
D2
The main enzymes that degrade dopamine are ______ and ______.
MAO, COMT
Serotonin is synthesized from the amino acid ______.
Tryptophan
The major breakdown product of serotonin is ______.
5-HIAA
Serotonin receptors are classified into multiple subtypes; 5-HT1 receptors are ______, while 5-HT2 receptors are ______.
inhibitory, excitatory
The ______ system is primarily involved in mood, sleep, appetite, and pain.
Serotonin
The cell bodies of serotonin-producing neurons are located in the ______ nuclei.
Raphe
Drugs that inhibit the reuptake of serotonin, such as ______, are commonly used as antidepressants.
SSRIs
Norepinephrine is primarily synthesized in the ______ and is involved in alertness and the fight-or-flight response.
Locus coeruleus
The major adrenergic receptors are classified into ______, ______, and ______ receptors.
alpha-1, alpha-2, beta
Alpha-1 adrenergic receptors are ______, while alpha-2 receptors are ______.
excitatory, inhibitory
The ______ system controls functions such as heart rate, arousal, and blood pressure through norepinephrine.
Sympathetic nervous
Acetylcholine is synthesized from ______ and acetyl-CoA.
Choline
The two major types of acetylcholine receptors are ______ and ______.
nicotinic, muscarinic
______ receptors are ionotropic and mediate fast synaptic transmission in the neuromuscular junction.
Nicotinic
______ receptors are G-protein coupled and are involved in parasympathetic nervous system functions.
Muscarinic
The ______ is a brain region where cholinergic neurons are involved in memory and learning.
Basal forebrain
Histamine is synthesized from the amino acid ______.
Histidine
Histamine plays a role in arousal and wakefulness through activation of ______ receptors.
H1
The H3 histamine receptor functions as an ______ receptor, regulating the release of histamine.
Autoreceptor
Histaminergic neurons are located primarily in the ______ nucleus of the hypothalamus.
Tuberomammillary
Endogenous opioids bind to ______ receptors, which are G-protein coupled and primarily inhibitory.
Mu, delta, kappa
The ______ receptor is responsible for most of the analgesic effects of opioids.
Mu
Opioid peptides such as ______ and ______ are naturally occurring ligands for opioid receptors.
Endorphins, enkephalins
The ______ system is involved in pain modulation, reward, and addiction.
Opioidergic
A ______ agonist mimics the action of a neurotransmitter by binding to the same receptor.
Direct
A ______ antagonist blocks the action of a neurotransmitter by binding to its receptor.
Competitive
A ______ modulator binds to a site on a receptor distinct from the agonist binding site, influencing receptor activity.
Allosteric
The breakdown of neurotransmitters by enzymes such as MAO and COMT is an example of ______.
Catabolism
The reuptake of neurotransmitters into presynaptic neurons is mediated by ______ transporters.
Plasma membrane
______ channels open in response to a change in membrane potential and are crucial for action potential propagation.
Voltage-gated
Ligand-gated ion channels, such as ______, open in response to the binding of neurotransmitters.
Ionotropic receptors
The ______ receptor is a G-protein-coupled receptor involved in dopamine transmission, reducing cAMP levels.
D2
The ______ receptor subtype mediates the fast excitatory action of glutamate in the brain.
AMPA
Activation of the ______ receptor by acetylcholine causes skeletal muscle contraction.
Nicotinic
The ______ receptor subtype is involved in slow excitatory postsynaptic potentials mediated by glutamate.
NMDA
Blocking the ______ receptor prevents dopamine from exerting its effects on reward and motivation.
D2
The precursor to serotonin is the amino acid ______.
Tryptophan
______ is an inhibitory neurotransmitter that opens Cl- channels to reduce neuronal excitability.
GABA
Glutamate is converted into ______ in glial cells, which is then transported back to neurons.
Glutamine
Serotonin is broken down by the enzyme ______ in presynaptic neurons.
Monoamine oxidase (MAO)
The ______ receptor binds to norepinephrine and mediates vasoconstriction in blood vessels.
Alpha-1
The ______ receptor is an inhibitory autoreceptor that decreases norepinephrine release.
Alpha-2
The ______ receptor is primarily found in the heart and increases heart rate when activated.
Beta-1
______ are G-protein coupled receptors that bind endogenous opioids like enkephalins and endorphins.
Opioid receptors
______ is a dopamine precursor that can be administered to patients with Parkinson’s disease.
L-DOPA
The ______ nucleus in the hypothalamus is the primary source of histamine in the brain.
Tuberomammillary
______ transporters remove GABA from the synaptic cleft to terminate its inhibitory effects.
GABA transporters (GAT)
The enzyme ______ is responsible for breaking down acetylcholine in the synaptic cleft.
Acetylcholinesterase
The ______ system controls involuntary functions like digestion and heart rate through acetylcholine release.
Parasympathetic
The ______ neurotransmitter system is involved in regulating mood, sleep, and appetite.
Serotonin
The neurotransmitter ______ is involved in pain suppression, and its receptors are targeted by opioids.
Endorphin
The ______ receptor subtype is primarily involved in inhibitory neurotransmission via chloride ion channels.
GABA-A
Increased levels of the neurotransmitter ______ are associated with schizophrenia.
Dopamine
______ is a neurotransmitter that plays a key role in the regulation of body temperature, sleep, and appetite.
Serotonin
The ______ receptors are located on the postsynaptic membrane and mediate excitatory neurotransmission.
Ionotropic
The enzyme ______ is involved in the catabolism of catecholamines like dopamine and norepinephrine.
Catechol-O-methyltransferase (COMT)
