neurotransmitters exam 2

glutamate

major excitatory signal, the most abundant neurotransmitter in the brain

where does glutamate originate from?

in the brain in neurons and glial cells

where does glutamate go to?

synaptic connections in CNS

how does affect behavior?

glutamatergic transmission uses ionotropic AMPA receptors that when activated lead to sodium entering the postsynaptic cell.

what does glutamate do to us?

regulates the CNS, arousal, learning, and memory

Serotonin (5-HT)

amine neurotransmitter derived from tryptophan

where does serotonin originate from?

synthesized in raphe nuclei (hypothalamus, thalamus, cortex, basal ganglia), fibers are throughout CNS

what does serotonin do to our behavior?

regulates mood, emotional behavior, sleep

what happens to serotonin inside terminal?

it is repackaged into vesicles and destroyed by monoamine oxidase (MAO) on outer membrane

what removes serotonin?

serotonin transporter and SSRI (selective serotonin reuptake inhibitors)

GABAergic neurons are a source of

synaptic inhibition

GAD

key enzyme in GABA synthesis (excitatory to inhibitory)

GABAergic system is the major..

inhibitory neurotransmitter system

what does GABA help with?

memory, cognitive function, decision making, anxiety, sleep

where does GABA go?

about 50% of brain tissue

GABA ionotropic receptors

GABAa and GABAc, fast

GABA metabotropic receptors

GABAb, slow

GABA neuropsychiatric role?

less GABA = less synchronization

what does GABA balence?

excitatory glutamate activity

dopamine (DA)

neurotransmitter critical for motivated behavior

where does dopamine travel to?

hippocampus, both pathways

dopamines role helps with

learning, memory, emotion, reward and motivation

neuropsychiatric conditions from dopamine?

parkinsons disease, schizophrenia, addiction

mesolimbocortical pathway

in substania nigra

mesostriatal pathway

VTA, goal-directed motor action

what type of receptors are dopamine?

metabotropic

excitatory dopamine receptors

D1-like (d1+d5)

inhibitory dopamine receptors

D2-like (d2, d3, d4)

D1 stimulates

adenylyl cyclase (increases cAMP)

increased cAMP increases PKA

PKA increases Ca2+ for transmitter release

D2 inhibits

adenylyl cyclase

AC is necessary for

catalyzing ATP to cAMP

a decrease in AC causes

decreased cAMP and cellular behavior

dopamine transporters play what role?

dictate the amount of dopamine available at the synapse

dopamine converts to

norepinephrine

norepinephrines role on our behavior

fight or flight, arousal , increases sympathetic nervous system, activating HPA axis

where is norepinephrine synthesized?

locus coeruleus

what type of receptors does norepinephrine have?

metabotropic

norepinephrine excitatory receptors

a1 + B

norepinephrine inhibitory receptor

a2

where does norepinephrine travel?

all over brain, limbic system

norepinephrine converts to

epinephrine

epinephrine (adrenaline)

increases arousal, peripheral fight or flight, does not cross blood brain barrier

epinephrine functions primarily in

PNS

norepinephrine primarily functions in

CNS

what are B receptors important for?

increasing cardiac output during stressful events

what receptors does epinephrine have?

adrenergic (same as norepinephrine)

cholinergic (Ach) neurons

motor neurons in brain and spinal cord

inhibited Ache causes?

decreased HR and blood pressure

acetylcholine (ACh)

endogenous ligand for cholinergic system

what is the cholinergic systems role?

alters cognition and perception

where does the acetylcholine go?

PNS and cholinergic system

acetylcholine ionotropic/nicotinic ACh receptors

ACh binds via sodium entering post-synaptic cell

NAchRs

primary signaling mechanismism at neuromuscular junction

acetylcholine metabotropic/muscarinic ACh receptors

either excites or inhibits increasing or decreasing potassium and calcium ions

acetylcholine neuropsychiatric disorder

alzeihmer’s