Psychopharmacology 2 Flashcards
What is self-administration
Drug infusion as a result of performance of a particular behaviour e.g. lever pressing
Looks at addiction
What is conditioned place preference/aversion
Assesses rewarding/aversive actions of drugs
Given drug and placed into arena and then control. Animal links specific area it is placed in e.g. floor texture and shape of area to the drug/control. If animal goes to drug area more and stays longer then has interest in that drug
What is drug discrimination
Investigate subjective response to drugs. To enable reward need to discriminate internal state and response appropriately.
E.g. - links behaviour of when on drug to drug so does the same thing but not seen with control
What is behavioural tolerance
Decrease in drug effectiveness at the same dose so more needed to give specific effect
What is behavioural dependency
Effects of cessation of drug following chronic treatment e.g. withdrawal effects
How does cannbinoids effect these behaviours
Very variable - tolerance , self-administration and place preference
Likely due to different strains, different species, different methodology
What is the main psychoactive drug in cannabis
Tetrahydrocannabinol (THC)
What are the cannabinoid receptors called
CB1 - brain, peripheral neurons, nerve terminals, controls neurotransmitter release
CB2 - elsewhere
What are the two endogenous ligands for cannabinoid receptors
Anadamide
2-archydonyl glycerol (2-AG)
Give some features of the cannabinoid receptors
Coupled to G proteins
Selective agonists identified
Selective antagonists identified
Endogenous ligands identified
Present in immune cells
What does cannabinoid (CB1) agonists do to food intake
Increase food intake
What does cannabinoid (CB1) antagonist (rimonabant) do to food intake
Significant decrease in food intake
What was seen with the CB1 antagonist AM251 over a 24hrs period in rats
Significant decrease in food intake, body weight and feeding behaviour over a 24hr and 12hr period - Riedel et al 2009
What was seen with the CB1 antagonist AM251 over a 4 days period in rats with repeated doses
Significant decrease in food intake, body weight and feeding behaviour over a 24hr and 12hr period - Riedel et al 2009
What was seen over a 2 day period with using THCV (novel chemical from marijuana without psychotic effects) in rats
Significant decrease in body weight, food intake and feeding orientated behaviours
Why are cannabinoid antagonists important
As they reduce feeding behaviour and food intake - possible obesity treatment
Why are cannabinoid agonists important
As they increase feeding behaviour and food intake - possible obesity model
Where are the CB1 receptors found in the CNS
Hippocampus - therefore indicates a role of cannabinoids in spatial learning and memory
What have studies using various behavioural paradigms shown regarding cannabinoid agonists
Induce impairments in spatial learning and memory
What role has SR141716A been shown to have on spatial learning and memory
Reverse these effects caused by cannabinoid agonists
What does CB1 knockout mice show regarding learning and memory
CB1 knockout mice also have enhanced learning and memory
What is the water maze and why is it important
Pool of water where the only way to get to land is a platform underneath the water surface where they can stand.
Important for spacial learning and memory, need to check animal vision first.
Expected that over-time they get quicker at finding the platoform.
How is vision checked with the water maze
Two striped pictures where they put the smaller lines where platform is and the mice linked the smaller stripes with the platform and kept going back to it.
Showed that cannaboids had no effect on mice vision.
What is WIN-2
WIN-2 is a chemical described as an aminoalkylindole derivative, which produces effects similar to those of cannabinoids such as tetrahydrocannabinol (THC) but has an entirely different chemical structure.