Recreational Drugs

Question 1

Describe the reward pathway

Answer 1

A Dopaminergic pathway from ventral tegmental area to the nucleus accumbens
Dopamine neurons in the ventral tagmentum area are inhibited by the gabaergic inhibitory internueron

Question 2

How does heroin act on the reward pathway?

Answer 2

Heroin removes the inhibition on the dopaminergic neurons in the VTA from the Gabaergic inhibitory interneurone therefore increasing the amount of dopamine in the synaptic cleft at the nucleus accumbens

Question 3

How do you treat heroin adiction

Answer 3

Methadone maintenance - it has a long half life and is orally active

• stabilise and maintain
• stabilise and withdraw

Buprenorphine (+naloxone) - sublingual administration

safe controlled heroin supply

Question 4

How does cocaine act on the dopaminergic pathway?

Answer 4

Blockade of dopamine re-uptake into nerve terminals in the nucleus accumbens

Question 5

How does amphetamine and methamohetamine act on the dopaminergic pathway

Answer 5

Substrates for dopamine transporter
Blockade of re-uptake of dopamine
Inhibition of enzymic degradation of dopamine by MAO
Stimulates dopamine release.

Question 6

Acute effects of amphetamine

Answer 6

Elevated mood	      	
Increased alertness		
Insomnia			
Increased stamina		
Anorexia			
Aggression			
Psychosis
Increased heart rate 	
Raised blood pressure

Question 7

Post amphetamine effects (after effects of drug have worn off)

Answer 7

Fatigue
Sedation
Depression
Dysphoria
Psychiatric disorders
Sustained raised BP

Question 8

What is methamphetamine (crystal meth/speed)

Answer 8

a more potent amphetamine

Question 9

What are the effects of methamphetamine?

Answer 9

Increased activity (includes sexual activity)
Reduced need for sleep (use in narcolepsy)
Decreased appetite
A general sense of well-being

Question 10

how long does methamphetamine last?

Answer 10

6-8 hours

Question 11

Side effects

Answer 11

After the initial rush there may be some violent behaviour

Question 12

How does MDMA work?

Answer 12

Causes 5-HT release

Inhibits 5-HT re-uptake - substrate for the transporter

Question 13

What drug can block the neurotoxicity of MDMA

Answer 13

Prosac

Question 14

Effects of MDMA

Answer 14

Elevated mood	      	
Increased alertness		
Insomnia			
Increased stamina
Perception disruption					
Increased body temperature				
Increased thirst										
5-HT syndrome (excess serotonergic activity)

Question 15

Post MDMA effects (after effects of drug have worn off)

Answer 15

Fatigue
Sedation
Depression
Dysphoria
Anxiety

Question 16

Adverse effects of MDMA

Answer 16

Depletion of 5-HT neurons

Loss of the 5-HT transporter

Question 17

What is the active ingredient in cannabis

Answer 17

Δ9- tetrahydrocannabinol (THC)

Question 18

What receptors does THC in cannabis act on?

Answer 18

CB1 and CB2 receptors

Question 19

what are the effects of cannabis?

Answer 19

Sedation
Feeling of well being 
Perceptual change (e.g. time)
Amnesia
Lowered temperature
Anti-emetic
Appetite stimulation
Analgesia

Question 20

What are the potential therapuetic applications for cannabis

Answer 20

Reduce nausea				
Increase appetite (anorexia)			
Reduce intraoccular pressure in glaucoma	
Control muscle spams			
Treat mild to moderate pain

Question 21

What are the long term effects of cannabis at a young age

Answer 21

high doses induce psychotic episodes

chronic use/early users have increased likelihood of developing schizophrenia (although it may increase the likleyhood of those already prone to getting it)

Question 22

What CB1 receptor antagonist was used as an anti-obesity drug to reduce apetite?

Answer 22

Rimonabant

Question 23

why was Rimonabant removed from the market?

Answer 23

It caused depression and suicidal thoughts

Question 24

Give 4 examples of hallucinogens

Answer 24

LSD
PCP
Ketamine
Salvinorin

Question 25

How does LSD work?

Answer 25

partial agonist at the 5-HT2c receptors

Question 26

How does PCP/Ketamine work?

Answer 26

NMDA receptor channel blocker

Question 27

How does Salvinorin work?

Answer 27

kappa opioid receptor agonist

Question 28

what are the acute effects of hallucinogens?

Answer 28

altered sensations		            		
visual disturbances				
euphoria					
psychosis					
panic
flashbacks

Question 29

what are the post hallucinogen effects?

Answer 29

panic attacks
flashbacks
psychiatric disorders

Question 30

Problems with ketamine use (acute and chronic)?

Answer 30

acute = GI cramps
chronic = severe bladder pain

Question 31

What receptor does nicotine act on

Answer 31

nicotinic acetylcholine receptors (nAChRs)

Question 32

effects of smoking

Answer 32

Smokers weigh about 4kg less than non-smokers, due to reduced food intake

Psychological dependence, physical dependence and tolerance

Life expectancy shorter due to health defects such as lung cancer

Smoking during the latter half of pregnancy significantly reduces birth weight

Question 33

What disease is smoking protective?

Answer 33

Parkinsons

Question 34

what does ethanol act on?

Answer 34

Enhancement of both GABA- and glycine-mediated inhibition

Inhibition of Ca2+ entry through voltage-gated calcium channels

Activation of certain types of K+ channel

Inhibition of ionotropic glutamate receptor function

Inhibition of adenosine transport.

Question 35

Adverse effects if ethanol

Answer 35

Aggressive behaviour
Incoordination (driving)
Neurotoxicity (chronic and binge drinking)
Liver damage
Impairment of fetal development