PS263 Lecture Notes - Lecture 15: Butyrophenone, Dopamine Transporter, Morphine
Document Summary
As the addiction progresses, the pleasure becomes weaker. Most commonly abused drugs come from plants. Nicotine comes from tobacco, caffeine from coffee and tea, opiates from poppies. Drugs either facilitate or inhibit transmission at synapses. A drug that blocks a neurotransmitter is an antagonist, whereas a drug that mimics or increases is an agonist. A drug has an affinity for a receptor if it binds to it, like a key into a lock. A drugs efficacy is its tendency to activate the receptor. A drug that binds to a receptor but fails to stimulate it has a high affinity but low efficacy. All or nearly all abuse drugs increase activity at dopamine and norepinephrine synapses. Olds and milner gave rats opportunity to press a lever to produce electrical self-stimulation of the brain. With electrodes in the septum and certain other places. Nucleus accumbens is central to reinforcing experiences of all types.
