Recreational drugs, pt. 1
Next, we'll cover a collection of recreational drugs that range from moderately safe to very dangerous. Note that some of these drugs may also be used therapeutically (e.g., amphetamine). We'll start with stimulants.
Stimulants
1) Watch these videos:
*It’s worth noting that, although MDMA is included in this list, it is not a classic stimulant. While it has stimulant properties, it also produces other psychoactive effects that distinguish it from typical stimulants (as discussed in the video).
2) Next, answer these questions to test your understanding:
1. Which of the following best describes the primary mechanism of action of cocaine in the brain?
- A. Inhibition of voltage-gated potassium channels
- B. Stimulation of serotonin synthesis
- C. Inhibition of monoamine reuptake
- D. Blockade of postsynaptic dopamine receptors
Show Answer
Correct answer: C
Cocaine binds to and inhibits the transporters responsible for the reuptake of dopamine, norepinephrine, and serotonin (monoamines) from the synaptic cleft, increasing their levels and prolonging their effects at synapses in the brain.
2. Which of the following is thought to be the primary mechanism of action of amphetamine in the brain?
- A. blocking the release of dopamine, norepinephrine, & serotonin
- B. increasing the release of glutamate
- C. increasing the release of dopamine, norepinephrine, & serotonin
- D. blocking the release of glutamate
Show Answer
Correct answer: C
Amphetamine enters neurons and disrupts the storage of monoamines (e.g., dopamine, norepinephrine, serotonin) in synaptic vesicles. This leads to high levels of free-floating monoamines inside the neuron. Amphetamine then can cause the monoamine transporters to run in reverse, leading to increased release of monoamines into the synaptic cleft. These elevated monoamine levels (especially dopamine & norepinephrine) are thought to be responsible for the main psychoactive effects of amphetamine.
3. Methamphetamine is FDA-approved in the United States to treat which psychiatric condition?
- A. depression
- B. ADHD
- C. panic disorder
- D. obsessive-compulsive disorder
Show Answer
Correct answer: B
Methamphetamine is approved by the FDA for the treatment of ADHD, and was commonly prescribed (as Desoxyn) in the 1960s to early 1970s to treat pediatric hyperactivity before tighter controls on the medication in 1971 led to a drastic decline in use.
4. Caffeine's stimulant effects are thought to be primarily attributable to its action as an ______________ at adenosine receptors.
- A. agonist
- B. antagonist
- C. allosteric modulator
- D. inverse agonist
Show Answer
Correct answer: B
Most of the effects of caffeine are thought to be traceable back to its action as an antagonist at receptors for the neurotransmitter adenosine, meaning it binds to and blocks adenosine receptors (reducing activity there). Adenosine receptors are thought to be involved in promoting sleep, so by blocking those receptors caffeine promotes wakefulness.
5. Nicotine's primary mechanism of action in the nervous system involves the direct stimulation of receptors for which neurotransmitter?
- A. acetylcholine
- B. serotonin
- C. norepinephrine
- D. histamine
Show Answer
Correct answer: A
Nicotine primarily exerts its effects by activating, or acting as an agonist, at certain receptors for the neurotransmitter acetylcholine. These receptors, known as nicotinic acetylcholine receptors, are found throughout the central and peripheral nervous systems.
