Lecture 3: Neurotransmitters cont. Flashcards
ACh: the basal forebrain, made of the ___ and ___, project to ____
medial septal nucleus; nucleus basalis
telencephalic regions
ACh: the midbrain region, made up of the ____ and ___, projects to (3)
pedunculepontine nucleus; laterodorsal tegmental nucleus
- diencephalon
- pontine and medulary reticular formation
- cerebellum
What is ACh’s role in the sympathetic NS? parasympathetic?
- preganglionic transmitter
2. pre + postganglionic transmitter
what is the postganglionic transmitter in the sympathetic NS?
norepinephrine
three major DA systems
- local circuit in hypothalamus
- nigrostriatal pathway
- VTA
projection of the nigrostriatal pathway
substantia nigra to caudate nucleus of basal ganglia
projection of VTA
cerebral cortex and limbic system
2 steps in DA synthesis (+ 2 optional next steps)
- tyrosine conv to dopa
- dopa conv to DA
- DA conv to NE
- NE conv to epinephrine
presynaptic catecholamine receptors (called ___) serve as a ____
- autoreceptors
2. negative feedback mechanism
if autoreceptors are blocked, synthesis and release are ____
increased
How is DA/NE transmitter action terminated?
reuptake into presynaptic terminal
____ degrades DA and NE in ___
MAO, presynaptic terminals - NTs not in vesicles
NE and ep act on which 2 types of receptors?
alpha and beta
DA acts on 6 receptors in 2 families: what are they?
D1 type: D1 and D5
D2 type: D2A, D2B, D3, D4
cell bodies that generate NE are located in ___, and project to (4)
locus coeruleus
- forebrain
- cerebellum
- brain stem
- spinal cord
serotonin is an ____
indolamine
site of action of SSRIs
presynaptic reuptake transporter
The 5-HT3 receptor is an ___, while the rest are ____
- ion channel
2. G-protein coupled second-messenger system
the key source of 5HT, ___, projects to (4)
raphe nuclei
- thalamus
- hypothalamus
- basal ganglia
- cortex
____ is the key transmitter in the spinal cord
glycine
precursor for serotonin
tryptophan
glutamate is ___ bandwidth when acting on ____
high, ionotropic receptors
glutamate receptors are found on ___
the surface of most neurons
precursor for GABA & enzyme involved
glutamate, glutamatic acid decarboxylase (GAD)
why can glutamate cause excitotoxicity?
permeability of NMDA ion channel to Ca2+
three ionotropic GluRs
- AMPA
- NMDA (N-methyl-d-aspartate)
- kainate
NMDA and AMPA control ___
fast excitatory synaptic transmission
ketamine and PCP are ____ at the ____ receptor
non-competitive antagonists
NMDA
NMDAR is unique in that it is ___
dually-gated
two conditions for dual-gated NMDAR
- ligand must be bound to receptor (ligand-dependent)
2. membrane containing receptor must be strongly depolarized (voltage-dependent)
two types of GABA receptors
GABAA, GABAB
GABAa receptors are ___acting ___channels permeable to ___
fast
ion
Cl-
influx of Cl- leads to ___, ___excitability
hyperpolarization, reducing
steps of GABA breakdown
- GABA
- glutamate
- glutamine
steps of GABA synthesis
- glutamine -> glutamate (glutaminase)
2. glutamate -> GABA (GAD)
GAD
glutamatic acid decarboxylase
opioid NTs are ___
opioid-type peptides
3 sites opiates agonize/activate
- mu
- kappa
- delta
the ___ receptor mediates analgesic and reinforcing properties of opiates
mu
Substance P is a ___ peptide that plays an important role as a ___
gut-brain peptide sensory NT (cause pain)
