Neurotransmitters

Question 0

Acetlucholine storage

Answer 0

Stored in synaptic vesicles on axonal terminal

Question 1

Acetylcholine synthesis

Answer 1

By all motor neurones in sc and brainstem
Acetly coenzyme A comes together eith choline precursors
Needs enzyme ChAT for reaction. Transfers acetate ion from acetylCoA to choline
Forms acetylcholine and coenzyme A
ChAT in EXCESS. increased choline increases amount of acetylcholine produced

Question 2

Acetylcholine release

Answer 2

Released into synaptic cleft upon arrival of AP and the influx of Ca2+
Binds to postsynaptic receptors (M1-5 muscarinic and nicotinic)

Question 3

Acetylcholine reuptake

Answer 3

Broken down by acetlycholiesterase

40-50% of broken down is taken up into presynaptic terminal by active transporter spcific

Question 4

Rate determining step for dopamine

Answer 4

The formation of L DOPA from tyrosine is the rate etermining step
Tyrosine hydroxylase is saturated

Therefore in treatments give LDOPA instead as dopa decarboxylase is not saturated

Question 5

Noradrenaline pathway

Answer 5

From locus coerulus

Through dorsal noradrenergic bundle to all pf cortex

Question 6

Noradrenaline helps with

Answer 6

Alertness
Arousal
Sensory perception
Motor tone

Question 7

Serotonin helps with

Answer 7

Sleep
Food intake
Thermoregulation
Sexual behaviour
Pain
Motor tone

Question 8

Cathecolamine reuptake

Answer 8

Selectively reuptaken by Na+ dependant transporters
Once in axon terminal are reloaded into vesicles
Or destroyed by MAO

Question 9

How are glutamate and glycine formed

Answer 9

Synthesised from glucose

Question 10

How is GABA formed

Answer 10

Glutamate with enzyme glutamic acid decarboxylase

Question 11

Glutamate gated channels

Answer 11

AMPA
NMDA
Kinate

Question 12

AMPA channel

Answer 12

Permeable to Na+ and K+
Most not permeable to Ca
Excitatory due to depolarisation
Coexists with NMDA

Question 13

NMDA receptor

Answer 13

Excitatory and admit Na+
But also permeable to Ca
And inward ionic current is voltage dependant

Question 14

NMDA receptor voltage openings

Answer 14

• At resting potential NMDA channel clogged with Mg2+ ions blocking passage of other ions
• when membrane is depolarised Mg2+ pops out (usually after AMPA channels opened)
• so glutamate opens channel but pore only unblocked when AMPA opens

Question 15

Intracellular Ca2+ actions

Answer 15

Trigger NT release
Activate enzymes
Regualte opening of many channels
Affect gene expression
Trigger cell apoptosis

Question 16

Dopaminergic projections

Nigrostriatal pathway

Answer 16

From substantia nigra
To caudate and putamen
Integration of sensory info and control of movement

Question 17

Dopaminergic projections

Mesolimbic/mesocortical

Answer 17

From ventral tegmental area
Go to nuclues accumbens, olfactory tubercle, amygdala, cingulate and prefrontal cortex.
Reward and reinforcement mechanisms (addiction), emotional behaviour and cognition

Question 18

Dopaminergic projections

Tuberoinfindibular pathway

Answer 18

From arcuate nucleus in hypothalamus
To median eminence
DA modulates hypothalamic-pituitary axis (inhibits prolactin secretion)