Week 123 - Depression

Question 1

What is the main excitatory neurotransmitter in the CNS?

Answer 1

Glutamine

Question 2

What does ‘excitatory’ neurotransmitter mean?

Answer 2

It means that an action potential is more likely to be fired by the neurotransmitter binding to its receptor.

Question 3

What does ‘inhibitory’ neurotransmitter mean?

Answer 3

It means that an action potential is less likely to be fired by the neurotransmitter binding to its receptor.

Question 4

‘Inhibitory’ and ‘Excitatory’ are ways to describe neurotransmitters, which are they most useful to describe?

Answer 4

Those that act on ionotropic neurotransmitters. Mostly for Glutamine and GABA, as other neurotransmitters tend to be more complicated.

Question 5

Which type of receptors does glutamine bind to?

Answer 5

Both ionotropic and metabotropic.

Question 6

What is the basic effect of prolonged activation of glutamine receptors?

Answer 6

Hyperexcitability, seizures.

Question 7

Name two substances that block glutamine receptors and thus cause sedation.

Answer 7

Alcohol and ketamine.

Question 8

What is the main ‘inhibitory’ neurotransmitter of the CNS?

Answer 8

GABA - Gamma-amino butyric acid

Question 9

What are the two types of receptor for GABA?

Answer 9

• GABAa - Ionotropic (Cl-), fast inhibition

* GABAb - Metabotropic, presynaptic inhibition of GABA release.

Question 10

What occurs when you activate GABAa receptors?

Answer 10

Sedation

Question 11

What class of drugs activates the GABAa receptors and what effect does this have?

Answer 11

Benzodiazepines, sedation.

Question 12

How does the date rape drug work?

Answer 12

It is a mixture of Benzodiazepines that activate GABAa receptors causing sedation, combine this with alcohol blocking glutamine receptors causing further sedation.

Question 13

What occurs when GABAa receptors are blocked?

Answer 13

Hyperexcitability > seizures.

Question 14

What is the name for the ‘other’ cells in the nervous system?

Answer 14

Glia

Question 15

Glia is the name for a group of other cells in the nervous system, what are there functions?

Answer 15

• Astrocytes - Support cells + damage repair
• Oligodendrocytes - Myelination of CNS
• Microlagia - Macrophrages of the nervous system.
• Ependymal cells - Produce CSF.
• ALSO, important for synthesis of both glutamate and GABA.

Question 16

Aside from GABA what is the other major inhibitory neurotransmitter of the central nervous system?

Answer 16

Glycine, but it’s boring.

Question 17

What are receptor type does Glycine have?

Answer 17

Ionotropic.

Question 18

What six functions is serotonin implicated in?

Answer 18

1) Depression
2) Apetite control
3) Nausea
4) Sleep
5) Sexual function
6) Analgesia

Question 19

Name three drugs from the GEM-F that use serotonin as a target.

Answer 19

• SSRIs - Fluoxetine
• SNRIs - Tramadol
• Ondansetron

Question 20

What are the five parts in the life of neurotransmitter that can be used as a drug target?

Answer 20

1) Receptors
2) Transporters
3) Affects
4) Breakdown enzymes
5) Sources of variation

Question 21

Out of the five parts in the life of a neurotransmitter what do SSRIs target for serotonin?

Answer 21

Transporters.

Question 22

What is serotonin also known as?

Answer 22

5-hydroxytrptamine

Question 23

What does an excess of serotonin cause in the GI system?

Answer 23

Diarrhoea and nausea.

Question 24

What are the four main conditions that causes disorder in the dopaminergic system?

Answer 24

1) Parkinson’s - Causes the death of neurones in the substantia nigra (which is one location for synthesis of dopamine)
2) Schizophrenia
3) Drug addiction
4) Tourette’s

Question 25

Which cells in the periphery produce histamine?

Answer 25

Mast cells.

Question 26

What are the three major types of opioids?

Answer 26

1) Endorphins
2) Enkephalins
3) Dynorphins

Question 27

What type of opioids means ‘morphine like’?

Answer 27

1) Endorphins

Question 28

What are the functions of endorphins?

Answer 28

• Analgesics

* Reward and motivation

Question 29

Give three examples of endorphins.

Answer 29

1) Morphine
2) Codeine
3) Tramadol

Question 30

What are the 5 core symptoms of depression?

Answer 30

1) Depressed mood
2) Tiredness after very little effort
3) Loss of interest
4) Reduced energy
5) Lasts more than 2 weeks

Question 31

What classes a ‘depressed mood’ in the core symptoms of depression?

Answer 31

• Diurnal variation
• Varies very little from day to day
• Unresponsive to circumstances

Question 32

What is mild depression?

Answer 32

• 2 core symptoms and two others

Question 33

What is moderate depression?

Answer 33

• 2 core symptoms and three or four others.

Question 34

What is severe depression?

Answer 34

• All core symptoms are severe and four others.

Question 35

What are the four main classes of antidepressants?

Answer 35

• Trycylcic antidepressants
• SSRIs (Selective serotonin reuptake inhibitors)
• Monoamine oxidase inhibitors
• ‘Others’ - SNRIs and receptor blockers.

Question 36

Which tricyclic antidepressant should NOT be prescribed?

Answer 36

Dosulepin

Question 37

What is the first line choice for antidepressants?

Answer 37

Citalopram - SSRI

Question 38

Which antidepressant should be first line treatment for those who have had cardiac disease/MI?

Answer 38

Sertraline as it does not prolong QT interval as citalopram does.

Question 39

The risk of withdrawal symptoms are most likely to occur in which SSRI?

Answer 39

Paroxetine

Question 40

Which antidepressant is most likely to be associated with death by overdose?

Answer 40

Venflaxine