Advanced Midterm Review Flashcards
What are the amine neurotransmitters? (6)
- Acetylcholine
- Norepinephrine
- Epinephrine
- Dopamine
- 5-HT (serotonin)
- GABA
What are the amino acid NTs? (3)
- Glutamate
- Glycine
- Aspartate
What are the purine NTs? (2)
- ATP
- Adenosine
What are the gas neurotransmitters? (3)
- Nitric Oxid
- Carbon monoxide
- Hydrogen sulfide
What are the two precursors of glutamate?
- alpha-ketoglutarate
- Glutamine
What percent of clinically marketed drugs are modulates of metabotropic receptors?
30%
What is the consequence of a missense mutation in the GNAS1 gene?
- McCune-Albright syndrome
- This gene encodes the Gsα subunit of G protein
- Mutation results in downregulation of cAMP signalling, causing deformity of bones, different pigment patches (cafe-au-lait) hormones hypersecretion and early puberty
How can receptors coupled to G protein cause Alzheimer’s disease?
With abnormal function of receptors coupled to G proteins, especially those involved in phosphoinositide hydrolysis
What is myasthenia gravis caused by? (3)
- Result of decreased nAChr expression in the postsynaptic site of neuromuscular junctions
- Caused mostly by T-lymphocyte dependent autoimmune reaction against nACHRs
or - Hereditary mutation of ε-subunit of nAChR
What is juvenile myoclonic epilepsy?
- An effect of missense mutation of the GABAa receptor α1 subunit,
- Accounts for 5-10% of all epilepsy patients
What are SH2 domains?
Src homology 2 - tyrosine binding domains
Proteins with these domains bind to phosphorylated tyrosines. They include enzymes such as PLC, IP3-Kinase and adaptor proteins such as growth receptor binding protein-2
What is an example of an intracellular receptor?
Glucocorticoid receptors
- The steroid receptor is retained in the cytoplasm by binding to HSP90
- Following ligand binding (with NO, H2S etc.) HSP90 is released and the receptor translocates to the nucleus.
- Steroid receptors bind to steroid response elements on DNA and result in upregulation of anti-inflammatory genes and downreguation of inflammatory cytokines
In the cerebral cortex, cholinergic synapses account for about ___ % of the total synaptic population
5-7%
What enzyme synthesizes acetylcholine?
Choline acetyl transferase (ChAT)
What is the homomeric nicotinic ACh receptor comprised only of α7 subunits characterized by?
High calcium ion permeability
What do α5 nicotinic receptor subunits do? Mutation of the gene encoding this subunit does what?
Controls nicotine intake
- Mutation of the CHRNA5 gene causes increased nicotine consumption.
- Also at higher risk for cancer and obstructive pulmonary disease.
- Neurons in the medial habenula are responsible for these effects.
What do α7 nicotinic subunit knockouts show?
Deficit in attention and working episodic memory.
What do β2 nicotinic receptor subunit -/- knockout mice show?
Model for sudden infant death syndrome (SIDS)
What percent of synapses in the brain are glutamatergic?
40%
True or false? There are more glutamate metabotropic receptors than ionotropic receptors
True.
8 metabotropic
3 ionotropic
What are ketamines used for? And what are they?
NMDA antagonist
Used for anaesthesia, with some neuroprotective functions
What Is dextromethorphan? What is it used for?
NMDA antagonist
Used as a cough suppressent
What is dizocilpine? What is it used for?
MK-801 NMDA receptor antagonist
Used to make animal models of schizophrenia and used for stroke and alzheimer’s prevention
Which metabotropic glutamate receptors are located postsynaptically? (2)
mGluR1 and mGluR5
Which metabotropic glutamate receptors are located presynaptically? (5)
mGluR2,3,4,7,8
Which metabotropic glutamate receptors are linked to Gq proteins? (2)
Group I
- mGluR1
- mGluR5
Which metabotropic glutamate receptors are linked to Gi/o proteins? (6)
Group II and III
- mGluR2,3 (Group II)
- mGluR4,6,7,8 (Group III)
Which type of receptor has the venus flytrap extracellular domain?
mGluRs
What percent of inhibitory synaptic activity is mediated by GABA? What percent of neurons is it in?
40%
And it is present in 20% of neurons
What inhibitory NT can also be found in the pancreas?
GABA
What receptor needs co-activation by both glutamine and glycine?
NMDA receptor
What do GABAb receptors do upon binding with GABA? (3)
- Inhibit cAMP
- Increase K+ conductance
- Decreases calcium ion conductance