Neurotransmitters

Question 1

Amino acid neurotransmitter

Answer 1

Excitatory- glutamate
Inhibitory- GABA (y amino butyric acid)

MAJOR

Question 2

Amine neurotransmitters

Answer 2

Monoamines

• catecholamines (tyrosine) dopamine, NA
• Tryptamines (tryptophan) serotonin

Others
-Ach

Modulatory

Question 3

What breaks down glutamate into GABA

Answer 3

GAD

Glutamic acid decarboxylase

Question 4

What takes GABA into vesicle

Answer 4

V-GABA transporter

vesicular GABA transporter

Question 5

What does the binding of GABA to GABAa ionotropic receptors cause

Answer 5

Influx Cl-
Hyperpolarisation
(benzodiazepans)

Question 6

Glutamate

Answer 6

Excitatory- Normal brain function
Sensory function (e.g. pain)
Learning/memory (slow, adaptive changes)

Question 7

GABA

Answer 7

Inhibitory Suppresses neuronal activity in the brain

Normal brain function

Question 8

Glycine

Answer 8

Inhibitory Suppresses neuronal activity in the spinal cord

Control of sensory/motor activity

Question 9

Ach

Answer 9

E/I Cognition
Memory
Arousal
Fine movement

Question 10

Dopamine

Answer 10

E/I Fine movement
Cognition/emotion
Pituitary hormone secretion

Question 11

Noradrenaline

Answer 11

E/I Mood

Blood pressure regulation

Question 12

Serotonin

Answer 12

E/I Mood
Hallucinations
Sleep/wakefulness

Question 13

Breakdown of tyrosine into NA

Answer 13

Tyrosine -> L-DOPA
catalyzed by Tyrosine hydroxylase (TH)

L-DOPA -> DA
Cat Aromatic L-AA decarboxylase (AADC)

DA taken into vesicle via (Vmat) vesicular monoamine transporter

DA converted to NA via Dopamine B hydroxylase

Question 14

What coverts DA to NA

Answer 14

Dopamine B hydroxylase

Question 15

Breakdown of tryptophan into serotonin

Answer 15

Tryptophan-> 5 hydroxy tryptophan
Via Tryptophan hydroxylase
5HT->serotonin 
via Aromatic l amino acid decarboxylase
serotonin taken vesicle via VMAT

Question 16

Starting point for 5 HT

Answer 16

Tryptophan

Question 17

What is the starting point for Na

Answer 17

Tyrosine

Question 18

What catalyzes the decarboxylation of L-DOPA and 5-hydroxytryptophan to dopamine and serotonin

Answer 18

Aromatic l amino decarboylase

Question 19

What uptakes serotonin back into pre synaptic membrane

Answer 19

SERT

Question 20

Imipramine

Answer 20

tricyclic drug developed in the 1940s for the treatment of psychosis
Increase mood
Blocks SERT

Question 21

Reserpine

Answer 21

anti-hypertensive drug used in the 1950s
decrease mood in some patients
Blocks VMAT

Question 22

Iproniazid

Answer 22

anti-tuberculosis drug used in the 1950s
Increase mood
Block MAO

Question 23

Methyldopa

Answer 23

anti-hypertensive [pro-]drug (used in pregnancy)
Decrease mood in some patients

Acts presynaptic inhibitory auto receptors

Question 24

Alpha- methyltyrosine

Answer 24

structural analogue of tyrosine – inhibits TH
Decrease mood

Question 25

TCA

Answer 25

Tricyclic antidepressants Block SERT/NET Increase NT synapse Amitriptyline

Question 26

SNRIs

Answer 26

Serotonin noradrenaline re uptake inhibitors Block NET/SERT increase NT synapse Venlafaxine, dulcoxetine

Question 27

SSRI

Answer 27

Selective serotonin reuptake inhibitors Block SERT flucoxetine, citalopram

Question 28

MAOIS

Answer 28

``` monoamine oxidase inhibitors Block MAO (monoamine oxidase) ``` Increase neurotransmitter available release phenelzine

Question 29

Atypical

Answer 29

monoamine receptor antagonists increase NA release Mirtazapine Alpha 2 antagonist

Question 30

Why MAOIs rarely used

Answer 30

Dangerous dietary interactions. Dietary tyramine (aged cheese, wine, cured meats) = similar in structure to tyrosine. Normally tyramine broken down by MAO enzymes in gut and liver but if you are taking MAOI = not able to break them down * tyramine is free to enter the circulation -> increased level of circulating tyramine -> reach post ganglionic sympathetic nerve terminal + tyramine taken up into pre synaptic neuron (due sim structure) taken up into vesicles pushing out NA into cytoplasm + MOA enzyme won’t work to break it down. Then get a built up of NA gradient causing the NA transporter to work in reverse pumping NA out into synapse. I Increased NA in synapse which have Alpha 1 adrenoceptors (smooth muscle contraction) * when they bind lead to vasoconstriction + massive hypertensive crisis. * if take the drug need to have a tyramine free diet.

Question 31

alpha 1 adrenoceptor

Answer 31

smooth muscle contraction - vasoconstriction