Neurotransmitter Systems Flashcards
Where does acetylcholine play a major role?
Striatum in Caudate putamen.
What is the function of the striatum?
Control of voluntary motion
What is the function of midbrain and pons?
Baseline excitation to cortex, REM sleep
How is ACh moved into clear vesicles?
VAchT
How is Ach removed from synaptic trough?
AChE
What are the two inhibitory amino acids
Glycine and GABA
Where is GABA distributed?
Increases in concentration from spinal cord to brain
Functions of GABA
consciousness, motor control and vision
What amino acid does GABA come from?
Glutamate
Enzyme used to make GABA
glutamate decarboxylase
How is GABA transported into vesicles?
Vesicular GABA Transporter protien
How is GABA removed from synapse?
GAT
What are the two forms of GAT?
1: on presynaptic terminal
2: on glial cells surrounding the synapse
What are the binding sites on GABAa receptors?
Benzodiazepine, ethanol, steroids.
What type of receptor is GABAaR?
ionotropic
What does GABAaR do?
activation produces ipsp
Function of extra-synaptic GABAaR
site of action for general anesthetics, including propofol.
What type of receptor is GABAbR
metabotropic
Where is GABAbR located
presynaptic: regulate NT release
postsynaptic: inhibition of post synaptic cell
What is coupled on GABAbR?
Gi/Go protein coupled
Function GABAbR
activate K channel, inhibits Ca channel
Function of Gly
mediates spinal inhibitions
How is Gly removed from synaspe
GAT proteins; recycling
What type of receptor is receptive to Gly
Ionotropic
What else can bind to GlyR
Ethanol and general anesthetics; stychnine blocks it.
What happens on GlyR
Chloride influxes, causes ipsp
Where is ATP/purines stored?
VNUT protein
ATP is primarily found in
cortex, cerebellum, hippocampus, basal ganglia
Two types of purine receptors
P1 and P2
What is the ligand that affects P1
adenosine
What is the function of P1 on presynaptic locations
inhibition of neurotransmitter release
Function of P1 on postsynapatic receptors
sleep induction, general inhibition of neural function
What type of P2 receptors exist
P2X and P2Y
What type of receptor is P2X
ionotropic
What binds to P2X
ATP
What typeof receptor is P2Y
metabotropic
What binds to P2Y
ATP, ADP, UDP, UTP
What is coupled on P2Y
Gi/Gq coupled
Function of P2 receptors
Learning and memory (with EAA), modified locomotor pathways
Where are peptide NT made?
In soma, transferred down the axon
What transmitters are peptides
opioids, tachykinins (substance P), cholecystokinin, somatostatin
What are the opioid peptides
endorphins, enkephalins, dynorphins, nociceptin
Function of opioids
Modify nociceptive inputs, affects mood and neurophysiology of drug addiction
What are the four precursor molecules of opioids
Proopiomelanocortinin
Pro-encephalin
Pro-dynorphin
Orphanin FQ
What is made from PCOM
B-Endorphins
What is the sequence of AA in Pro-encephalin
YGGF-X
Metenkephalin is M
Leuenkephalin is L
What makes up Pro-dynorphin
3 molecules of Leuenkephalin and dynorphin
What is made in Orphanin FQ
nociceptin
What enzymes take up the opioids
enkephalinase and aminopeptidase
What is the metabotropic opioid receptor
Mu, Kappa and Delta
What does activation of the Mu receptor cause
analgesia, respiratory depression, euphoria, constipation and sedation
What does activation of the Kappa receptor cause
analgesia, dysphoria, diuresis, miosis
What does activation of Delta receptor cause
Analgesia
What does the Mu receptor lead to ionically
increase in potassium efflux and hyperpolarization
What does Kappa and Delta receptors lead to ionically
Decrease calcium influx
What are the endogenous endocannabinoids
Anadamide, 2-Arachidonylglycerol
Endocannabinoids have effect what in the basal ganglia
mood and motor performance
Endocannabinoids effect what in the spinal cord
modulation of nociception
Endocannabinoids affect what in cortex
neuroprotection
Endocannabinoids affect what in hippocampus
memory formation
Endocannabionids affect what in hypothalamus
control of body energy/hunger
What are endocannabinoids synthesized from
arachidonic acid
What receptor responds to endocannabionids
CB1 and CB2
Function of CB1
Reduces EAA and GABA release
Function of CB2
antiinflammatory, also increases Beta amyloid removal
Location of CB2
microglia in brain, Gut, Immune system