Sort each drug action as an agonist (enhances the transmitter's effect) or an antagonist (reduces it).
Groups: Agonist · Antagonist
- An SSRI blocks serotonin reuptake, leaving more serotonin in the cleft
- Nicotine binds and activates ACh receptors
- Naloxone occupies opioid receptors and blocks endorphins
- A drug that mimics GABA and opens its channel
- Curare occupies ACh receptors without activating them, causing paralysis
Hints
- Ask about the NET effect on the transmitter's action, not whether the drug 'blocks' something.
- Blocking reuptake leaves MORE transmitter around - so it enhances the effect, making it an (indirect) agonist.
Show the answer
Agonist: Nicotine binds and activates ACh receptors, An SSRI blocks serotonin reuptake, leaving more serotonin in the cleft, A drug that mimics GABA and opens its channel
Antagonist: Curare occupies ACh receptors without activating them, causing paralysis, Naloxone occupies opioid receptors and blocks endorphins
Agonists enhance a transmitter's effect - directly (nicotine, GABA-mimic) or indirectly (an SSRI blocks reuptake, boosting serotonin). Antagonists occupy the receptor without activating it (curare, naloxone). The SSRI is the classic trap: 'blocks' a process yet ENHANCES the transmitter, so it is an agonist.
Practise Neurotransmitters
The app has 7 more questions on this lesson, and keeps your place in the course. Psychology I is free to start.
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