Brainscape's Knowledge GenomeTM

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


See full index

Pharmacology #2 > Opioids > Flashcards

Opioids Flashcards

1
Q

The nociceptors are what?

A

A delta and C fibers

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

Which fibers mediate the first response to pain, sharp pain?

A

A delta

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

C fibers are responsible for what kind of pain?

A

Dull, aching, or burning pain

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

Are there more C and A delta fibers?

A

More C fibers

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

What are some things that can turn on a nociceptor?

A

Heat, cold, mechanical perturbations, or protons

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

T/F pain and inflammation go hand in hand?

A

True

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

What are some ways that we can diminish pain?

A

We can inhibit signaling to the CNS- stop signal transmission to the brain.
We can inhibit CNS activity
We can have inhibition at the periphery- (anti-inflammatories)

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

What drugs inhibit signaling to the CNS?

A

Local anesthetics

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

What drugs inhibit CNS activity?

A

Opioids

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

What are the three opioid receptors? and what kind of receptors are they?

A

Mu (sign for micro)
Kappa (k) and
Delta
They are all G protein coupled receptors that activate the Gai protein

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

b-endorphin is the natural agonist of what?

A

The mu-opiod receptor

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

The dynorphin’s A, B and alpha/beta net-endorphin are the agonists for which opioid receptor?

A

k-opioid receptor

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

What happens when you activate the opioid receptors?

A

The opioid receptor activates the Gai and GbetaGgamma subunits of the G protein.
Activation of Gi leads to the inhibition of adenylate cyclase activity, which ends up decreasing the cAMP levels as well as a reduction in the PKA activity. If there isn’t PKA activity then there is a reduction of Ca++ entry from voltage gated channels.
Also, a particular potassium channel is going to be opened and this hyper polarizes the cell, making it more difficult to get an action potential

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

Let’s look at the synapse- the presynaptic terminal, the synaptic cleft and the post synaptic terminal. What effects will a reduction of Ca++ and hyper polarization produce at the synapse?

A

Presynaptically, Ca++ is required for transmitter release. Inhibition of the voltage sensitive Ca++ channel and hyper polarization will both diminish Ca++ entry. Presynaptically, opioids will reduce transmitter release.
Postsynaptically, hyper polarization will make it more difficult to generate an action potential.

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

There are 3 mu receptors. Which ones are most important?

A

mu1 and mu2 are physiologically important.

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

What do mu receptors in the GI tract do?

A

They inhibit peristaltic action in the GI tract- this causes constipation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the natural agonist of the mu-opioid receptor?

A

Beta-endorphin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where are mu receptors found?

A

GI tract, periqueductal gray, superficial horn of the spinal cord, nucleus accumbins, amygdala, cerebral cortex

19
Q

The majority of the analgesic drugs act where?

A

The majority of analgesic drugs primarily acts at mu receptors

20
Q

Do opioids modulate the response to pain? If endogenous opioids were weakening the response to pain, you would think that inhibition of those receptors would increase pain sensitivity.

A

Opioids don’t seem to modulate the baseline response to pain. (see slide 24)

21
Q

T/F opioids inhibit GABA release? Then what happens?

A

True, GABA is inhibited. Remember that GABA is inhibitory itself, so if you inhibit the inhibitor then you are basically activating something. The something in this case is activating the pathway that produces the CNS mediated inhibition of pain.

22
Q

What are the two components that influence pain?

A
  1. sensory-discriminative component

2. emotional components (your brain processing what’s going on)

23
Q

All opioid analgesics produce the following:

A

analgesia, respiratory depression, constipation, gastrointestinal spasm, and physical dependence

24
Q

Which drug is your prototypical full agonist of the mu (u) receptor?

A

Morphine

25
Q

T/F morphine produces sedation- make you fall asleep?

A

False, it does not put you to sleep

26
Q

When you take morphine without being sedated, patients report that pain is still present, but it’s not unpleasant (is that still pain then?). What does this suggest?

A

This suggests that the effects on the motivational-affective component (the emotional component) might be very important.

27
Q

What is the most serious acute, adverse effect of all opioids?

A

Respiratory depression

28
Q

Fun fact- opium was once used to treat diarrhea in infants and children.

A

And some opium for you and some for you

29
Q

Can you develop tolerance to morphine?

A

Yes

30
Q

What are the effects of tolerance to morphine?

A

Well, it doesn’t develop uniformly to all effects of the drug, but usually tolerance is manifested by a shortened or diminished analgesia

31
Q

Tolerance is linked to what?

When does tolerance usually start happening?

A

The dose and frequency of administration.

It starts around a week after treatment (5-7 days)

32
Q

Is dependence the same as tolerance?

A

Nope

33
Q

How is morphine metabolized in the liver? What are the primary and secondary products?

A

It is metabolized by the enzyme UGT2B7.
M-3-G is the primary product
M-6-G is the secondary product

34
Q

Out of morphine, M-6-G and M-3-G, which one(s) can cross the blood brain barrier?

A

Morphine and M-6-G can cross the BBB

35
Q

Out of morphine, M-6-G and M-3-G, which are agonists to the mu receptor?

A

Both Morphine and M-6-G are mu agonists, with M-6-G being the better agonist.

36
Q

Why doesn’t morphine work when taken orally?

A

Because if taken orally it has to be broken down and half of it is converted to an inactive form and then excreted.

37
Q

T/F codeine is a better oral drug than morphine. Why or why not?

A

True because in the initial metabolism in the liver only 5% of it is converted to morphine. The rest is converted to C-6-G, which is an active compound

38
Q

Should pain be treated without also administering an anti-inflammatory?

A

Nope, they should go together

39
Q

What are some opioid antagonists?

A

Naloxone, naltrexone, and nalmefene

40
Q

What are opioid antagonists used for?

A

They are used to treat opioid toxicity.

They block opioid receptors from being bound by the opioid agonist

41
Q

T/F all three of the opioid receptors (mu, kappa, and delta) provide an analgesic effect (pain relief)?

A

True

42
Q

Do all the opioid receptors have similar side effects?

A

No, the mu receptor clearly has the most side effects whereas kappa and delta don’t have hardly any side effects other than pain suppression

43
Q

Opioids are used to treat pain. Those available for oral administration are:

A

codeine, hydrocodone, oxycodone, pentazocine

Pharmacology #2 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions