Sedative Hypnotics

Question 1

What is the mechnanism of action of benzodiazepines?

Answer 1

1. Non-specific positive allosteric modulators of the GABA-A receptor at the benzodiazepine site
2. This enhances the action of GABA
3. This enhanes the frequency of chloride channel opening resulting in ↑Cl- influx (sedative effects)

Question 2

What is the mechnanism of action of Z-drugs?

Answer 2

1. Specific positive allosteric modulators of the BZ1 (ω1) subtype of the benzodiazepine binding site on the GABA-A receptor complex (high affinity for α1-containing GABA-A receptors)
2. This enhances the action of GABA
3. This enhanes the frequency of chloride channel opening resulting in ↑Cl- influx (sedative effects)