Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Fundamentals of Pharmacology > L10: Drugs affecting SYM NS 1 > Flashcards

L10: Drugs affecting SYM NS 1 Flashcards

1
Q

3 branches in the peripheral nervous system

A

1) Somatic NS
2) Autonomic NS
3) Enteric NS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does sympathetic NS prepare us for?

A

Flight or fight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does efferent nerves of the sympathetic NS leave?

A

Spinal cord in the thoracic & lumbar regions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Role of adrenal medulla

A

Controls hormones that initiates fight or flight responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Main hormones secreted by the adrenal medulla

A

1) Epinephrine (Adrenaline)
2) Norepinephrine (Noradrenaline)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What acts as neurotransmitters in the sympathetic NS?

A

ACh & noradrenaline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do post-ganglionic nerves in the SNS release?

A

Noradrenaline as their neurotransmitter = noradrenergic nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Features of the postganglionic nerves

A

Varicosities: ‘swellings’ along their length wich releases noradrenaline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

1st step of synthesis pathway for noradrenaline

A

Begins with amino acid tyrosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the 2nd step; “rate-liming step”

A

Conversion of tyrosine to DOPA by enzyme** tyrosine hydroxylase ** which is the slowest step

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

3rd step of synthesis of noradrenaline

A

Synthesis of dopamine occur in the cell cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

4th step; conversion of dopamine

A

conversion of dopamine to noradrenaline by enzyme dopamine beta-hydroxylase in synaptic vescicles within varicosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Role of the drug carbidopa

A

Inhibits the enzyme DOPA decarboxylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

5th stage of synthesis of noradrenaline & adrenaline

Noradrenaline to adrenaline

A

**Chomaffin cells ** of the adrenal medulla contain **phenylethanolamin N-methyl transferase (PNMT) ** that converts noradrenaline to adrenaline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

6th step: what happens when it is stimulated?

A

Adrenal medulla releases a mix of adrenaline (95%) & noradrenaline (5%) into the blood stream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Role of drug a-methyl tyrosine

A

Inhibits tyrosine hydroxylase which secretes a lot of adrenaline

17
Q

Release of noradrenaline

How is exocytosis triggered?

A

Increase in intracellular conc of Ca2+ ions caused by Ca2+ entering the channels, opened by an AP

18
Q

Release of noradrenaline 2

How does the released noradrenaline act?

A

Act on receptors found on target tissue but some act on a2-adrenoreceptors found on varicosity

19
Q

How can release of noradrenaline be inhibited?

A

“Noradrenergic neurone blocking” drug guanethidine

20
Q

How do noradrenaline & adrenaline produce their effects by doing?

A

Activating “adrenoceptors”

21
Q

Define adrenoceptors

A

A group of nine 7-transmembrane receptors comprising of 3 main types: a1, a2, and a3

22
Q

Which 4 main types of adrenoceptor is used to explain drug action?

A

a1, a2, b1, b2

All GPCRs (G-protein coupled receptors)

23
Q

Removal of noradrenaline

1st step of removal

A

Once released, about 75% of noradrenaline is removed from synapse & taken back into the varicosity by Uptake-1 carried out by the norepinephrine transporter (NET)

24
Q

Removal of noradrenaline

2nd step: What happens to the remaining 25% of noradrenaline?

A

Taken up into other cells by Uptake-2 carried out by extraneuronal monoamine transporter (EMT)

25
Q

What 2 things can happen to the noradrenaline when it is inside the varicosity?

A

1) Taken back up into the synaptic vesicles by VMAT
2) Destoryed by enzyme Monoamine Oxidase (MAO)

26
Q

What does NET stand for?

A

Norepinephrine transporter

27
Q

Role of norepinephrine transporter (NET)

A

Remove neurotransmitters from synapses

28
Q

1 drug that inhibits NET

A

Cocainel; increase extracellular concentration of noradrnealine in both peripheral & CNS

29
Q

How can recycled noradrenaline be can increased further?

A

By **monoamine oxidase ** which repackages them into vesicles

30
Q

What food do patients who take MAOIs cannot have?

A

Cheese

31
Q

Why does this “cheese reaction” occur?

A

MAO is found in cells of gut for breaking down dietary tyramine
1. Normal intake of cheese results in little tyramine
2. MAOI drug, tyramine reaches blood stream

Tyramine is a “indirectly acting sympathomimetic” drug
1. Taken up to sympathetic nerves (through NET) into synaptic vesciels where it displaces noradrenaline out of vesicles

32
Q

Role of amphetamine

A

Increase extracellular concentration of noradrenaline in the CNS

33
Q

How does amphetamine do its job?

A
  1. Act like tyramine
  2. Inhibiting MAO, enzyme busy breaking down amphetamine & can’t break down noradrenaline
34
Q

Role of antidepressant fluoxetine

A

Inhibits uptake of neurotransmitter seronin in the brian

35
Q
A

Fundamentals of Pharmacology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions