Neurotransmitters and Their Receptors Flashcards
A lot of this material will probably be covered later, and the details will hopefully be more relevant. If you don't care about pontomesencephalotegmental complex right now... that's probs ok.
Basic stuff: What are the two main types of synapse in body?
Electrical - like in the heart. Connected cytoplasms. Quick, can’t modulate.
Chemical - what we care about with the neurotransmitters and stuff.
What are the two types of potentials that can be induced in the post-synaptic cell?
Excitatory Post-Synaptic Potential (EPSP)
Inhibitory Post-Synaptic Potential (IPSP)
What’s another name for ligand-gated ion channel receptors for neurotransmitters?
Ionotropic receptors.
What’s another name for neurotransmitter receptors that are GPCRs?
metabotropic receptors
What types of ions to excitatory ionotropic receptors usually use? Ligands?
Cations. Glutamate and ACh.
What kind of ions do inhibitory ion receptors usually use? Ligands?
Anions. GABA, glycine
What’s faster, an ionotropic or a metabotropic receptor?
Ionotropic is faster. Makes sense.
How is receptor diversity facilitated in ionotropic receptors?
Receptor subunits can be reshuffled to form receptors with different activities.
What can a metabotropic receptor do that an ionotropic receptor can’t? (3 things)
- can amplify signal through 2nd messenger systems
- alter gene expression (and make other cellular change) through 2nd messenger signaling
- sustain signaling for a longer duration
Can metabotropic GPCR subunits be recombined?
Nope, they’re a monomer.
What 4 things must a neurotransmitter have/do?
- Specific synthesis
- Specific release mechanism
- Post-synaptic effects
- Method for inactivation (degradation, reuptake)
What are 3 ways in which neurotransmitter activity can be terminated?
Degradation, reuptake, diffusion.
4 types of molecules that can be neurotransmitters?
Amino acids
Small molecules - ACh
“Biogenic amines”
Peptides
Serotonin, histamine, and catecholamines. Are these NTs excitatory or inhibitory?
Excitatory. (as are glutamate and ACh, but that’s easy)
Are GABA and glycine excitatory or inhibitory NTs?
Inhibitory.
What’s the main excitatory CNS NT?
Glutamate!
Name 3 ionotropic glutamate receptors.
NMDA, AMPA, and Kainate Receptors.
What are the metabotropic receptors for glutamate listed?
mGluRs… okay, that’s not quite profound
How can NMDA receptors get blocked? (endogenously, not drugs) Significance?
NMDA channels in hyperpolerized cells can get blocked by Mg2+. Thus NMDA receptors will only work when the cell is repolarized.
3 uses for NMDA-R blockers?
Alzheimer’s-Parkinson’s
Anesthetics (ketamine)
Drugs of abuse (PCP)
What happens to AMPA and Kainate receptors when you repeatedly stimulate them?
They desensitize.
What’s the main inhibitory NT in the brain?
GABA!
What are the two main GABA receptors? Ionotropic or metabotropic?
GABA-A - Ionotropic - uses Cl-
GABA-B - Metabotropic
(don’t worry about GABA-C, it’s only in the retina.. but it’s also ionotropic)
What allosteric modulators can act on GABA-A? (classes of drugs, name 4)
Barbituates, benzodiazapines, anesthetics, steroids.
Contrast GABA-A and GABA-B. Speed? Duration? Ions modulated?
Speed: A is fast, B is slow
Duration: B lasts longer.
Ions: A uses Cl-, B modulates Ca++ and K+
What drugs act on GABA-B?
Baclofan (for spasticity)
GHB (date rape…… no good :( )
Ecstasy (a way better idea than date rape, but still a bad idea)
So you know about nicotinic and muscarinic receptors for ACh (don’t you? ish?). Are they ionotropic or metabotropic?
Nicotinic is ionotropic.
Muscarinic is metabotropic.
When are nicotinic receptors expressed in the brain?
Early in life. Expression declines later.
Do cholinergic systems modulate dopanergic systems? (relevant Parkinson’s)
Yes. (But not being a neuro person, I have no idea what this means.)
Acronym for cholinergic toxidrome (too much ACh)?
SLUDGE
Salivation, lacrimation, urination, diarrhea, GI distress, emesis
What’s the mnemonic for things that cause an anticholinergic toxidrome?
A bunch of “A” things: Atropine, antihistamines, antidepressants, antipsychotics, antiparkinsonian drugs.
(something about hatters, bones, and beets)
Where is norepinephrine synthesized? Where does it go?
In the “locus coeruleus.” It goes everywhere.
Where is serotonin made? Where does it go?
Made in the raphe nuclei. It goes everywhere.
Where is dopamine made? Where does it go?
Made in ventral tegmental area and substatia nigra. Goes to prefrontal cortex, caudate nucleus and putamen, nucleus accumbens. Professor emphasized that it goes to the basal ganglia
Where is ACh made (in the brain). Where does it go?
Septal nuclei, nucleus basalis, pontomesencephalotegmental complex (must have been named by a German). Goes… lots of places.
What was causing the syndrome of the case of the woman with psychosis, agitation, fever, seizures, unstable heart rate/BP, and abnormal muscle movement.
Autoantibodies against NMDA receptors.
What was the root cause of these anti-NMDA-R antibodies?
Ovarian teratomas -> antibodies produced via a paraneoplastic syndrome
