Exam #01f - Opioids & Multi-MOA Analgesics

Question 1

Name (2) endogenous opioid peptides?

Answer 1

1. endorphins

2. enkephalins

Question 2

This term is defined as awareness of a sensory stimulus (pain that you can describe)?

Answer 2

sensation

Question 3

This term is defined as the effect component of pain (how you think about a specific pain)

Answer 3

perception

Question 4

Opioid receptors are distributed throughout the body including the CNS, PNS, GI tract, immune cells, and lung. What clinical relevance do opioid receptors in immune cells serve?

Answer 4

In vivo, morphine decreases immune function, however, there is no definitive evidence that giving morphine to cancer patients is inhibiting their immune function or giving fatal outcome

Question 5

True or False - opioid receptors in the lungs cause respiratory depression?

Answer 5

False - nobody is sure why opioid receptors are in the lungs

Question 6

List the steps of the opioid MOA?

Answer 6

1. opioid binds to 7TM-GPCR
2. binding activates Gi protein
3. Gi inhibits adenylate cyclase
4. this decreases [cAMP]
5. this decreases intracellular Ca2+
6. this results in decreased release of NT

Question 7

The two primary sites of action of opioids are the presynaptic neuron and postsynaptic neuron. Explain what ions are affected at these two locations?

Answer 7

Presynaptic neuron - opioid binding inhibits Ca2+ influx and inhibits NT release

Postsynaptic neuron - opioid binding enhances K+ efflux and hyperpolarizes neuron

Question 8

Name the (8) CNS effects of opioid binding to opioid receptors?

Answer 8

1. analgesia
2. euphoria
3. sedation
4. respiratory depression
5. constipation
6. cough suppression
7. miosis
8. N&V

Question 9

True or False - all opioids inhibit cough due to opioid receptors in the brain stem and not the lungs?

Answer 9

True

Question 10

Morphine activity is attributable to its (2) metabolites, morphine 6-glucuronide and morphine 3-glucuronide. Which metabolite can lead to CNS toxicity? If an individual forms one metabolite but not another, do this individual still get analgesic effect?

Answer 10

morphine 3-glucuronide can lead to CNS toxicity

yes

Question 11

Name the (11) mu opioid receptor (MOR) agonists?

Answer 11

1. morphine
2. meperidine
3. methadone
4. hydromorphone
5. heroin
6. hydrocodone
7. oxycodone
8. oxymorphone
9. fentanyl
10. codeine
11. buprenorphine

Question 12

True or False - fentanyl is a good drug for both transdermal and epidural

Answer 12

True

Question 13

Which MOR agonist is a prodrug for morphine?

Answer 13

Codeine

Question 14

Which MOR agonist is approved for opioid abuse treatment as a transdermal patch?

Answer 14

Buprenorphine

Question 15

Name the (2) MOR antagonists?

Answer 15

1. Naloxone

2. Naltrexone

Question 16

Which MOR agonist is used to treat “addicts?”

Answer 16

Methadone

Question 17

Which MOR agaonist is used in CV surgery?

Answer 17

Fentanyl

Question 18

Which MOR agonist causes the release of histamine: morphine or fentanyl?

Answer 18

Morphine causes release of histamine, fentanyl does NOT

Question 19

Which MOR agaonist is used as a cough suppressant?

Answer 19

Codeine

Question 20

Which (2) opioids are used as antidiarrheals?

Answer 20

1. Diphenoxylate + atropine (Lomotil)

2. Loperamide (Imodium)

Question 21

Which MOR agonist can cause a muscular rigidity SE?

Answer 21

fentanyl

Question 22

Is Tramadol a centrally acting or peripherally acting analgesic?

Answer 22

Centrally acting

Question 23

True or False - Tramadol is an NSAID

Answer 23

False - it is NOT

Question 24

How does Tramadol’s dual mechanism of action differ from Tapentadol’s?

Answer 24

Tramadol - metabolite M1 opioid agonist and non-opioid component is NE & 5-HT reuptake inhibitor

Tapentadol is the same except it is only a NE reuptake inhibitor