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Flashcards in Pharmacodynamics Deck (77)
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1

What are the four main locations that drugs act on?

1. Receptors
2. On DNA
3. Enzymes
4. Membranes

2

What drugs stimulate receptors?

Agonists

3

What drugs prevent receptor stimulation?

Antagonists

4

What do receptors do?

They initiate cellular responses

5

What are receptors?

Proteins in or on cells?

6

What are the four main types of proteins that receptors are linked to?

1. G-protein coupled receptors
2. Ion channels
3. Gene transcription
4. Enzymes

7

Name a Beta2 adrenoceptor agonist

Salbutamol

8

Name a Beta2 receptor antagonist

Propanol

9

Name a H1+2 receptor agonist

Histamine

10

Name an opiate Mu receptor agonist

Morphine

11

Name an opiate Mu receptor antagonist

Naloxone

12

Name a M2 muscarinic agonist

Acetylcholine

13

Name a M2 muscarinic antagonist

Atropine

14

How do G protein coupled receptors interact with ion channels?

They cause confirmation changes which allow ion exchange

15

How to G protein coupled receptors affect enzymes?

They activate or inhibit enzymes which will result in second messengers being produced or inhibited

16

What are the two types of opioid analgesics?

1 - Morphine based
2 - Synthetic

17

What are the three main opioid receptors?

Delta, Kappa and Mu

18

What type of receptors do opioids act on?

G-Protein Coupled Receptors

19

What occurs after receptor binding of opioids?

1. Inhibition of adenylate cyclise -> decreased intracellular cAMP
2. Couple to K:Ca ion channels -> inhibition of transmitter release and postsynapse excitability

20

75% of presynapse receptors for opioids are....?

Mu receptors

21

By what 3 means do opioid analgesics work?

1. Inhibits pain transmission in dorsal horn
2. Activates descending pathways in grey matter inhibiting pain transmission (reduced GABA)
3. Inhibits nociceptive afferents in tissues

22

How is pain transmission inhibited at the dorsal horn?

By inhibiting presynaptic afferent impulses

23

How are the descending pathways activated?

By inhibiting GABA release in periaqueductual grey matter (PAG)

24

Why does activating the descending pathways inhibit pain?

It inhibits the discharge of the Dorsal Horn

25

What does the dorsal horn project into?

The Thalamus

26

What does the thalamus project in to?

The Cortex

27

Why does respiratory depression occur when morphine is administered?

The activation of Mu receptors reduce the respiratory centres sensitivity to CO2

28

Why can nausea and vomiting occur when morphines administered?

Activation of the chemoreceptors trigger zone

29

Why can pupillary constriction occur when morphine is administered?

Activation of the kappa receptors leads to the stimulation of the oculomotor nucleus (parasympathetic NS)

30

Why is it important to be cautious when administering morphine to someone with asthma?

It can cause histamine release leading to bronchospasm and hypotension