Neurotransmitters Flashcards
steps of synaptic communication
- AP
- Ca2+ ion channels open
- Ca2_ entry triggers vesicle docking and secretion
- NT release
- response on cell
- degradation by enzymes, reuptake, or diffusion out of synaptic cleft
most abundant NT in PNS
ACh
where is ACh synthesized
axon terminal
what is the enzyme that synthesizes ACh
choline acetyl transferase (CAT)
what breaks down ACh, where?
acetylcholinesterase at synaptic cleft into acetate and choline
what makes ACh
acetyl CoA and choline
T or F: there are lots of cholinergic nuclei in the CNS
F: relatively few but have widespread projections
what causes alzheimers
progressive loss of cholinergic neurons = decrease in ACh signalling
what is myasthenia gravis caused by
autoimmune destruction of nAChR at motor endplate = less receptors
treatment for myasthenia gravis
AChE inhibitors- prolong time AChE is in the cleft
catecholamines are derived from
tyrosine
serotonin is derived from
tryptophan
histamine is derived from
histidine
what degrades biogenic amines
MAO and COMT
how many types of MAO are there
2
MAO-A and MAO-B
biogenic amines
catecholamines (NE, E, DOPA), histamine, serotonin
what neurons produce DA
dopaminergic neurons
are dopaminergic receptors (D1-5) metabotropic or ionotropic
metabotropic
loss of DAergic neurons in ____ ____ leads to motor deficits = parkinsons
basal ganglia
excess DA results in
schizophrenia, hallucinations, paranoia
what is a key NT in reward pathways
DA
deficits of adrenerguc activity is associated with
depression
how many types of 5HT receptors are there? are they metabotropic or ion
14 types
metabotropic mostly, one ionotropic
what takes up 5HT, what breaks down 5HT?
SERT
MAO
5HT cell bodies are in
brainstem
SSRIs do what
block reuptake of 5HT for treatment of depression
what neurons produce Glu
glutamatergic neurons
what are the 3 ionotropic Glu receptors
NMDA, AMDA, kainate
are glu receptors ionotropic or metabotropic
both
AMDA is a channel for what
NA
NMDA is a channel for
Ca2+ with Mg2+ block
main excitatory NT in CNS
Glu
loss of DAergic neurons results in excess activity of ___ pathways
glu
= parkinson’s
what is the main inhibitory NT in the brain
GABA
which GABA receptor is metabo, which is iono
GABAb = met GABAa = ion
GABAa is a channel for
Cl-
what is the main inhibitory NT in brainstem and spinal cord
Gly
gly receptors are _____ and let in
ionotropic
Cl-
gly reuptake is done by
T1 adn T2
what is a coagonist with Glu for the NMDA receptor
Gly
purines include
ATP
adenosine
GTP, AMP, ADP
receptors P2X and P2Y are
ionotropic
endogenous opioids are
neuropeptides
what do enkephalins do
are endogenous opioids that suppress pain
where are the neurons for enkaphalins
brain and dorsal horn
substance P is a
neuropeptide
substance P plays a role in
pain sensation
released by some primary afferents
examples of endogenous opioids
enkephalins
endorphins
is NO stored
no
endocannabinoid targets
CB1 and CB2
endocannabinoids are synthesized from
membrane phospholipids
2 most common endocannabinoids
anandamide
2-archidonylglycerol
