cannabis Flashcards
what is cannabis produced from?
Cannabis Sativa
(Hemp)
what does THC stand for?
(delta 9) tetrahydrocannabinol
what is THC?
psychoactive agent
what is a psychoactive agent?
- drugs or substances that affects how the brain works
- causes changes in mood, awareness, thoughts, feelings, behaviour
where can you find THC?
- primarily in sticky resin secreted in flowering tops of female cannabis plans
- all parts of plant
identify some uses of cannabis
used to make:
- rope
- cloth
- paper
- seeds for oil
- birdfeed
what forms can cannabis come in?
- marijuana
- sinsemilla
- Hashish (“solid”)
- Hash oil
describe marijuana
- dried crumbled leaves
- flowering tops of cannabis plant particularly dried down
- small stems
- usually smoked in joints, pipes, bongs
- THC content varies
explain how a bong works
- have water in bong
- put weed in the socket/cone
- finger covers any air holes
- burn the weed
- mouth over opening of bong
- inhale
- water cools down smoke
- When you lift finger, you inhale all the smoke that has been accumulating
- airflow of smoke into lungs
- exhale
describe sinsemilla
- variant of marijuana
- treated specially
- pollination is prevented
- done by keeping female plant separate
- preventing pollination increases potency of THC (increasing content of marijuana
describe hashish
- condensed resin from plant
- potency varies with concentration
describe hash oil
- hashish reduced to alcoholic extract
- single drop placed into joint
where is cannabis thought to be originated from?
China / Asian region
where is Hashish more commonly used?
Arab world
how much cannabis does a typical joint contain?
0.5 - 1 gram
How much THC is in 1gram of cannabis?
40mg (of active substance)
what % of original THC is absorbed from lungs into blood plasma?
20%
Outline Black et al. (1998) study that looks at increasing THC absorption
- instructed ppts to smoke joint and hold breathe for either 7 seconds or 15 seconds
- ppts that were instructed to hold breathe for 15 seconds reported experiencing an increased high
what happens after peak level of THC being absorbed into blood plasma?
- THC concentration falls
- this is through metabolism in liver and fat storage
what happens after peak level of THC being absorbed into blood plasma?
- THC concentration falls
- this is through metabolism in liver and fat storage
what is the half life of THC plasma concentration
20 - 30 hours
(half life: time is takes for amount of drugs active substance in body to reduce by half)
what did Devane et al. (1988) discover?
discovered that you could identify the location of cannabis receptors in the brain
how did Devane et al. (1988) go about identifying the location of cannabis receptors in the brain
- looked at scans of rat brains
- found that cannabis receptors are consistent with behavioural effects
- receptors cluster around regions that primarily have behavioural effects
give examples of where cannabis receptors are located and the behavioural effect that is consistent with cannabis use
cluster of receptors in hippocampus
- effects spatial memory
cluster of receptors in the substantia nigra
- indicates cannabis has effects of reward system
identify the name of the cannabis receptor
CB1 receptor
what is the agonist (what increases the activity of the receptor)?
THC
what is the antagonist (what decreases the activity of the receptor)?
SR 141716
identify acute behavioural effects of cannabis (Iversen, 2000)
- the “buzz”
- the “high”
- being “stoned”
explain ‘the “buzz”’
- lasts briefly
-feelings of light-headedness, dizziness
explain ‘the “high”’
- quickly follows ‘the buzz’
- feelings of euphoria, exhilaration
- disinhibition to brain system
- ## disinhibition gives rise to ‘giggles’
explain ‘being ‘“stoned”’
- achieved with large amount of marijuana
- feelings of calm, relaxed, dreamlike
- sensations of floating, enhanced visual and auditory perception
- slowing of perception of time
- changes in sociability (can increase/decrease)
what are some psychopathological effects of taking cannabis?
- paranoia
- anxiety
- panic
- more common in first time users OR after taking very high dose
identify physiological effects of cannabis
- increased blood flow to skin -> sensation of warmth
- increase in heart rate -> sensation of a pounding pulse
- increase in hunger
- hyperphagia (increase in appetite)
- palatability (increase in likeness of food)
briefly explain how Williams & Kirkham (2002) provide evidence for hyperphagia/increase in appetite/the munchies
- introduced THC
- reported feelings of hunger
- found that introducing the antagonist (SR141716) suppressed feelings of hunger
- palatability also increases in rats upon administering THC
Outline Huestis et al. (2001) study into antagonistic effects
(effects of marijuana when antagonist is administered)
- had ppts smoke joint containing 2.46% THC
- one group administered with CB1 antagonist - SR 141716
- other group administered a placebo
- collected self-report
- had ppts record their responses
- ppts in placebo group reported feeling more high than those in antagonist group
- same with feeling stones and heart rate
outline Agurell et al (1986) study into administration effects
(effects of marijuana depending on how it is consumed)
- compared blood plasma level of THC following smoking a joint vs oral consumption
- when smoking joint, THC goes through lungs and into blood plasma
- when ingesting marijuana, THC goes through digestive tract, then metabolised in liver
- found that in smoking marijuana, THC levels in blood plasma are high but drop off quickly
- found that in orally digesting marijuana, THC levels are higher in concentration and last longer
Outline Curran et al (2002) study into oral THC administration on verbal memory
- administered ppts with either a placebo, 7.5mg THC and 15mg THC
- found that relatively low dose has few effect on verbal memory
- high dose of cannabis greatly impairs verbal memory
- however, effect of cannabis is reduced in long term users
- low doses = few effects on cognitive function UNLESS task is demanding
outline 2 studies that show the effects of administering antagonist
Richardson et al (1988)
- found SR 141716 induces hyperalgesia (increase in pain sensitivity)
- administering cannabis reverses this
Black (2004)
- found SR 141716 reduces food consumption
- administering cannabis increases food consumption
