Brainscape's Knowledge GenomeTM

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


See full index

Y2 LCRS 1 - Pharmacology and Therapeutics > Drugs of Abuse 1 – General/Cannabis > Flashcards

Drugs of Abuse 1 – General/Cannabis Flashcards

1
Q

Generally speaking, how do the drugs of abuse cause the feeling of euphoria?

A

The hijack the mesolimbic dopaminergic pathway – the central reward pathway

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

Describe the structure of the central reward pathway.

A

The dopaminergic neurones project from the ventral tegmental area to the nucleus accumbens
Dopamine release into the nucleus accumbens will stimulate the feeling of euphoria

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

Put the routes of administration of drugs in order of speed of absorption.

A

Smoking > IV > Snorting > Oral

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

Why is smoking slightly quicker than IV injections?

A

Smoking brings the drug to the alveoli where it easily crosses the alveoli and enters the pulmonary circulation
There is a shorter distance from the pulmonary circulation to the heart and then to the brain than from the site of IV injection to the heart and then to the brain

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

What are the different classes of the drugs of abuse?

A

Narcotics/painkillers – e.g. opiate like drugs
Depressants – e.g. alcohol
Stimulant – e.g. cocaine, caffeine
Miscellaneous

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

What is an alkaloid?

A

Any class of nitrogenous organic compound of plant origin that has profound physiological actions on humans

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

What are the active components of the Cannabis sativa plant?

A

Cannabinoids (there are over 60 of them in the plant)

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

What is the most potent cannabinoid in the plant?

A

Delta-9-tetrahydrocannabinol (Delta-9-THC)

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

What is another important cannabinoid that appears to counteract some of the negative effects of the potent cannabinoid?

A

Cannabidiol

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

How has cannabis production changed over the last 10-15 years?

A

There has been an increase in the amount of 9-THC in the cigarette meaning that there is less cannabidiol
This suggests that cannabis production is heading towards being morepro-psychotic

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

What percentage of smoked cannabis will reach the blood stream?

A

Around 30%

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

Describe the accumulation of cannabis in the brain following administration.

A

Cannabis levels in the brain rise very quickly after administration but, because the brain is highly perfused, the cannabis levels in the brainfall rapidly as well

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

Describe the accumulation of cannabis in fat following administration.

A

Cannabis is very lipid soluble so it slowly accumulates in the fat
This means that cannabis will leak from the store in the fat for a long time after administration

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

How long will the effects of cannabis last after smoking a joint?

A

Around 30 days (because of the storage in adipocytes)

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

What is an important metabolite of cannabis?

A

11-hydroxy THC (this is more potent than Delta-9-THC)

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

What happens to this metabolite once it has been produced?

A

It is excreted in the bile into the GI tract but then it undergoes enterohepatic cycling and re-enters the blood stream where it can exert its physiological effects
Because of this, plasma Delta-9-THC levels are a poor measure of intoxication

17
Q

Where are the different cannabinoid receptors found?

A

CB1 – brain

CB2 – peripheral immune cells

18
Q

What type of receptor is the cannabinoid receptor?

A

G protein coupled receptor – negatively coupled with adenylate cyclase

19
Q

Name one endogenous cannabinoid.

A

Anandamide

20
Q

Describe how cannabis causes euphoria.

A

Cannabis binds to CB1 receptors on GABA neurones and inhibits the GABA neurones
This means that they remove the inhibitory influence of GABA neurones on the dopaminergic neurones of the rewards pathway, hence there is increased firing of the dopaminergic neurones –> euphoria

21
Q

What area of the brain does cannabis interact with that is linked to its psychotic effects?

A

Anterior Cingulate Cortex

There is hypoactivity in the anterior cingulate cortex in chronic cannabis users

22
Q

What is this part of the brain responsible for?

A

Performance monitoring and behavioural adjustment

23
Q

Which part of the brain does cannabis act on to stimulate food intake?

A

Lateral hypothalamus

24
Q

What are the two main groups of neurones that are involved in stimulating appetite?

A

MCH (melanin concentrating hormone) neurones

Orexin neurones

25
Q

What effect does cannabis have on these neurones?

A

Cannabis inhibits the inhibitory effect of GABA on MCH neurones, thus leading to increased MCH firing
Cannabis also directly stimulates orexin production
This leads to hunger

26
Q

Describe the effect of cannabis on the immune system.

A

Cannabis is a powerful immunosuppressant

27
Q

How does cannabis cause memory loss?

A

It inhibits the production of BDNF (brain derived neurotrophic factor), which is important in the hippocampus in forming memories
In general, cannabis has a depressant effect on the hippocampus

28
Q

How does cannabis cause impaired psychomotor performance?

A

It depresses the cerebral cortex

29
Q

How does cannabis cause cardiovascular effects?

A

Cannabis acts via the TRPV1 receptor to cause calcium influx

30
Q

What are the cardiovascular effects of cannabis?

A

Activating the TRPV1 receptor leads to calcium influx –> tachycardia

31
Q

In which part of the body does cannabis cause a lot of vasodilation?

A

Conjunctivae (bloodshot eyes)

32
Q

Why is it not possible to overdose on cannabis?

A

There is very low expression of CB1 in the medulla (which is where you find the cardio-respiratory centres)

33
Q

What is the upregulation of cannabinoid receptors in the adipocytes associated with?

A

Obesity

34
Q

State 4 drugs that are either cannabinoid agonists or antagonists.

A

Dronabinol - Delta-9-THC
Nabilone - Delta-9-THC
Sativex - Delta-9-THC + cannabidiol
Rimonabant – CB1 antagonist

35
Q

What can cannabinoid receptor agonists be used for?

A

Treatment of nausea due to chemotherapy

36
Q

What is Sativex used for?

A

Treatment for symptom improvement in adult patients with moderate to severe spasticity due to multiple sclerosis

37
Q

What can Rimonabant be used for?

A

Anti-obesity medication (it was removed from the market because it was shown to cause depression and suicidal thoughts)

Y2 LCRS 1 - Pharmacology and Therapeutics (38 decks)

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