Lecture #4
Drugs
3 categories of drugs:
1) Depressants (downers)
-anything that calms/slows body function or neural activity
-e.g. heroin, alcohol
2) Stimulants (uppers)
-anything that stimulates/quickens/excites neural activity or body function
-e.g. cocaine, nicotine
3) Hallucinogens
-anything that distorts perception - causes perception sensory images
without sensory input
-e.g. marijuana, LSD
The effects on neurotransmitters of 5 drugs (heroin, cocaine, alcohol, nicotine, marijuana)
1. Heroin (depressant)
-“Runners’ High”
- pleasurable feeling from vigorous exercise, created by the release in the
brain of endorphins (a peptide neurotransmitter)
-controls the pain caused by overusing muscles
-“Endorphins” = a contraction of “endogenous morphine”
-they are the body’s natural morphine
-chemically similar to the class of drugs called opiates (e.g. heroin,
morphine)
-Agonists - opposite of antagonists
-fit into receptor sites and causes the same effect on the cell as the
neurotransmitter would
-Opiates are agonists for endorphins
-they fit into the endorphin receptor sites and mimic their action
-release from pain - bond to opioid receptor sites and produce pain-free,
pleasurable feelings of endorphins
-If you get addicted to heroin
-the brain changes its release of endorphins; it will stop natural production
of endorphins because it is getting them from an outside source
-when you stop taking heroin, it causes withdrawal
-it is very painful because you have little to no endorphins because
your body stopped making them
Drugs
3 categories of drugs:
1) Depressants (downers)
-anything that calms/slows body function or neural activity
-e.g. heroin, alcohol
2) Stimulants (uppers)
-anything that stimulates/quickens/excites neural activity or body function
-e.g. cocaine, nicotine
3) Hallucinogens
-anything that distorts perception - causes perception sensory images
without sensory input
-e.g. marijuana, LSD
The effects on neurotransmitters of 5 drugs (heroin, cocaine, alcohol, nicotine, marijuana)
1. Heroin (depressant)
-“Runners’ High”
- pleasurable feeling from vigorous exercise, created by the release in the
brain of endorphins (a peptide neurotransmitter)
-controls the pain caused by overusing muscles
-“Endorphins” = a contraction of “endogenous morphine”
-they are the body’s natural morphine
-chemically similar to the class of drugs called opiates (e.g. heroin,
morphine)
-Agonists - opposite of antagonists
-fit into receptor sites and causes the same effect on the cell as the
neurotransmitter would
-Opiates are agonists for endorphins
-they fit into the endorphin receptor sites and mimic their action
-release from pain - bond to opioid receptor sites and produce pain-free,
pleasurable feelings of endorphins
-If you get addicted to heroin
-the brain changes its release of endorphins; it will stop natural production
of endorphins because it is getting them from an outside source
-when you stop taking heroin, it causes withdrawal
-it is very painful because you have little to no endorphins because
your body stopped making them
