Medical Terminology

allosteric modulator

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Allosteric modulators are substances that indirectly influence or modulate the effects of an agonist at a receptor. For example, with respect to the GABAA receptor, positive allosteric modulators increase the activity of the GABAA 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 GABAA receptor protein. (Examples of negative allosteric modulators or inhibitors of GABAA activity are flumazenil, bicuculline, pentylenetetrazol, and gabazine.)