AP Psychology: Agonists, Antagonists and Psychoactive Drugs

Agonists, Antagonists and Psychoactive Drugs

directly impact neurotransmitters at the synapse

Agonists

enhances action of neurotransmitters

Direct Agonists

mimic the effects of the neurotransmitter by binding to the receptor of the next neuron

Indirect Agonists

Can block reuptake of neurotransmitters (reuptake inhibitor)

Heroin

Direct Agonist of endorphins. Receptor sites cant distinguish between endorphins and the chemical structure of heroin

Opiates/Opioids

Nicotine

Direct agonist of ACh. It stimulates skeletal muscles and causes an increase heart rate

Black Widow Venom (A Toxin)

Direct agonist of ACh. Causes it to be released continuously at neurotransmitters junctions

Prozac

inhibits reuptake of serotonin

Cocaine

inhibits reuptake of dopamine and elevates serotonin and norepinephrine

intense euphoria, alertness and heightened self confidence

crash after high dissipates - high withdrawal symptoms

Antagonists

binds to receptors but dont stimulate it. Block Neurotransmitters to bind to dendrites. Inhibits of normal functioning of Neurotransmitters

Botox

antagonist of ACh. Affected muscles cant move

Thorazine

Antagonist of dopamine by blocking their receptors

An early drug for schizophrenia

Depressants

Slows or inhibits central nervous sytem functions

creates drowsiness, sedation and sleep

relieve anxiety and lower inhibition

combination of them may be deadly

Alcohol

Agonist of GABA

lessens inhibition by depressing brain centres responsible for judgement and self control

Opiates/Opioids

agonist of endorphins

very addictive with powerful withdrawal symptoms

Oxycodone

Opiates/Opioids

Fentanyl

Opiates/Opioids

Stimulants

Activates sympathetic nervous system

increases brain activity, arouse behaviours and increased mental alertness

caffeine

promotes wakefulness, alertness and faster thought processing by stimulating release of dopamine

physically addictive and creates withdrawal symptoms

antagonist of adenosine: blocks sleep inducing effects

Hallucinogens (psychedelics)

sensory and perceptual distortions, alter mood and effects thinking

useful in therapeutic settings

THC - mild

produces sense of well being, mild euphoria, dreamy state of relaxation

interferes with muscle coordination, learning, memory and overall cognitive function

various therapeutic uses