Glossary

allosteric modulator

Allosteric modulators are substances that indirectly influence or modulate the effects of an agonist at a receptor. For example, with respect to the GABA_A receptor, positive allosteric modulators increase the activity of the GABA_A receptor protein in the central nervous system of mammals. (Examples of positive allosteric modulators include alcohol, benzodiazepines [such as Valium], benzodiazepine-receptor agonists [such as Ambien or Lunesta], anesthetic gases, and propofol.) In contrast, negative allosteric modulators inhibit or decrease the activity of the GABA_A receptor protein. (Examples of negative allosteric modulators or inhibitors of GABA_A activity are flumazenil, bicuculline, pentylenetetrazol, and gabazine.)