MT - Neurotransmitters and Receptors Flashcards
Give some examples of small-molecule neurotransmitters.
Any of: Acetylcholine, glutamate, GABA, glycine, aspartate, dopamine, norepinephrine, serotonin, etc.
Give some examples of neuropeptide neurotransmitters.
Any of: vasopressin, somatostatin, oxytocin,angiotensin II, etc.
What are 3 examples of small molecule neurotransmitters that aren’t contained in vesicles?
- Endocannabinoids (lipid soluble)
- Nitric Oxide (gas)
- Carbon monoxide (gas)
What is the rate limiting step during dopamine production?
Tyrosine hydroxylase.
Where in the brain are cholinergic neurons localized?
The nucleus accumbens, medial septum, nucleus basalis, medial habenula, laterodorsal tegmental nucleus (LDT), etc.
Where in the brain are noradrenergic neurons localized?
In the locus coerulus.
Where in the brain are the sorotinergic neurons localized?
In the Raphe nucleus
What is the prefix used to denote subunits of the AMPA receptors?
“Glu”.
What is the prefix used to denote subunits of the NMDA receptors?
“Glu”.
What is the prefix used to denote subunits of the Kainaite receptors?
“Glu”.
What is the prefix used to denote subunits of the serotonin receptors?
“5-HT”.
What is the prefix used to denote subunits of the purine receptors?
“P2X”.
What differentiates GABAa from GABAb
GABAa: ligand gated ion channel
GABAb: GPCR (metabotropic)
What are the 3 types of Gα subunits?
- Gα s
- Gα i/o
- Gα q
What does Gα s protein binding cause?
Activates adenylate cyclase (AC), which produces cAMP and stimulates protein kinase A (PKA).
What does Gα i/o protein binding cause?
Inhibits adenylate cyclase (AC), which stops producing cAMP and therefore inhibits protein kinase A (PKA).
What does Gα q binding cause?
Activation of phospholipase C (PLC-β).
What are some examples of secondary messengers?
Any of: calcium, cGMP, cAMP, phosphatidyl inositol.
What enzyme synthesizes cAMP?
Adenylate cyclase (AC).
What enzyme synthesizes phosphatidyl inositol?
Phospholipase C (PLC-β).
What do muscarinic receptors control?
Heart contractility.
When a muscarinic receptor in the heart is activated, what do the associated G-proteins do?
Gα subunit: dephosphorylates (closes) calcium channels
Gβ/γ subunit: activates (opens) potassium channels
Through what receptor/messenger/signalling pathway does epinephrine act on the heart? Elaborate.
Activates GPCRs -> AC -> cAMP -> PKA -> open Na+ and Ca2+ channels.
What effect does epinephrine signalling have on the rate of depolarization in the heart? What is the overall physiological effect?
Increases rate of depolarization and therefore heart rate.
NMDA receptors are highly permeable to _____.
Calcium.
What is another term used to describe an NMDA receptor?
A “coincidence detector”.
Extracellular Mg2+ blocks ____ receptors.
NMDA.
Where does GABA bind on the GABAa receptor?
At the αβ interfaces.
