Unformatted text preview: ne (peyote cactus) Cannabis (Marijuana) Pharmacology of Cannabis • • • • Active constituent of Cannabis is D9Tetrahydrocannibinol (THC) THC binds to Cannabinoid receptors to increase DA release in the nucleus accumbens Cannabinoid receptors: CB1 & CB2 Anandamide is the natural “endogenous” ligand for these receptors Effects of Cannabis Cortex: motor/sensory, Cingulate cortex: judgement Hippocampus: blunts memory, Cerebellum: blunts motor coordination Neuroleptics Neuroleptic/Antipsychotic: literally to ‘seize’ neurons to control abnormal neuron activity • Anti-schizophrenic o (e.g. Chlorpromazine) o Antidepressants o (e.g. Tricyclic’s like imipramine) 0 Depressants
Depressant: Depresses activity • • • Benzodiazepines Barbituates Alcohol* (stimulant at low doses) Pharmacology of Nicotine and Alcohol Both increase dopamine release in nucleus accumbens • • Nicotine o Nicotinic receptors (Acetylcholine) Alcohol o GABAA receptor agonist o NMDA glutamate receptor antagonist Modulates opioid peptide system (mu receptors) 6 Reward • Reward: positive reinforcement • Initial exposure to certain drugs will produce feelings of reward: o Elation o Excitement o Relaxation • Usage reinforced (repeated) becomes a • drug of abuse • How do we know dopamine is involved? Reward Pathway: Dopamine (DA) @Reward Pathway: Dopamine (DA) The mesolimbic dopamine system Nucleus accumbens: NA Ventral Tegmental Area: VTA • Increased DA in the nucleus accumbens makes a substance rewarding • Natural rewards (sex, food, nurturing) also increase dopamine in the nucleus accumbens Reward &...
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- Three '10
- nucleus accumbens