Drugs Of Abuse

Question 1

What is considered the main brain reward pathway

Answer 1

Dopamine Mesolimbic pathway VTA- nucleus accumbens

Also mesocortical

Question 2

What drugs increase dopamine release

Answer 2

Opiates 
Nicotine
Amphetamine
Cocaine
PCP
Ethanol
Cannabis
Ecstasy 
Barbiturates
Caffeine

Question 3

What does Lsd and ecstasy increase the release of

Answer 3

Serotonin

Question 4

Where do the serotonin pathways project to

Answer 4

Prefrontal cortex
Frontal Cortex
Hippocampus

Question 5

what is serotonin involved in?

Answer 5

Mood
Memory processing
Sleep
Cognition

Question 6

How do opiates work

Answer 6

Opioid receptors- G protein coupled receptors decrease AC decrease cAMP , open K channels and close Ca channels, reduces NT release and excitability

Question 7

What are the general effects of opiates

Answer 7

Euphoria
Analgesia
Resp depression 
Sedation 
Itching 
Nausea

Question 8

What are some chronic effects of opiates

Answer 8

Anhedonia 
Constipation
Depression
Insomnia
Dependence 
Tolerance

Question 9

On withdrawal from opiates what is the effect

Answer 9

Craving 
Restlessness
Insomnia 
Muscle and bone pain
Diarrhoea 
Vomiting
Cold flashes and goose bumps
Kicking movements

Question 10

How does cocaine work?

Answer 10

Blocks Na+ channels

Increases catecholamine NT function by preventing reuptake (DA) most important

Question 11

How do amphetamines work

Answer 11

Release monoamines from neural storage vesicles and blocks re-uptake transporters meaning there is increased
DA NA + 5HT in the synapse

Question 12

What are the effects of amphetamines

Answer 12

Increased wakefulness 
Concentration 
Decreased fatigue and appetite 
Performance enhancing 
Euphoria 
Increase libido
Self esteem and confidence 
Aggression
Obsession 
Paranoia

Question 13

What are some chronic effects of amphetamines

Answer 13

Increased cardiovascular tone and bp

Tachycardia

Question 14

What is the action of ecstasy

Answer 14

Releases monoamine NTS

DA NA 5HT

Question 15

What are the ‘negative’ effects of ecstasy

Answer 15

Interference with temp reg
Severe hyperthermia
Liver/kidney/CV system failure and death

Question 16

What is the action of cannabis

Answer 16

THC mimics effects of small endogenous lipid messengers

Inhibits wide range of NT release via G protein coupled cannabinod receptors

Question 17

How does cannabis stimulate appetite

Answer 17

Actions on feeding centres in the hypothalamus and possibly in the gut

Question 18

What are some polling term effects of alcohol

Answer 18

Neuropathic 
Wernickes encephalopathy
Myopathies
Hepatotoxicities 
Haematological disorders
Obesity
Suicide

Question 19

What drugs are used to substitute drugs of abuse

Answer 19

Methadone for heroine/opiate abuse - decreases opiate craving

Question 20

What antagonist are used to reduce drug abuse

Answer 20

Naltrexone- in opiate

Mecamylamine- nicotine ( blocks reward)

Question 21

Define dependence

Answer 21

Strong desire or sense of compulsion to take the substance
Difficulties in controlling use
Physical withdrawal state
Tolerance
Progressive neglect or other interests- more seeking taking and obtaining
Persistence despite detrimental effects