- Inverse agonist
In
pharmacology , an inverse agonist is an agent which binds to the same receptor binding-site as anagonist for that receptor and reverses constitutive activity of receptors. [cite journal |author=Kenakin T |title=Principles: receptor theory in pharmacology |journal=Trends Pharmacol. Sci. |volume=25 |issue=4 |pages=186–92 |year=2004 |pmid=15063082 |doi=10.1016/j.tips.2004.02.012 |url=] Inverse agonists exert the opposite pharmacological effect of a receptor agonist. Inverse agonists are effective against certain types of receptors (e.g. certainhistamine receptor s andGABA receptors [cite journal |author=Mehta AK, Ticku MK |title=Ethanol potentiation of GABAergic transmission in cultured spinal cord neurons involves gamma-aminobutyric acidA-gated chloride channels |journal=J. Pharmacol. Exp. Ther. |volume=246 |issue=2 |pages=558–64 |year=1988 |pmid=2457076 |doi= |url=http://jpet.aspetjournals.org/cgi/pmidlookup?view=long&pmid=2457076] ) which have intrinsic activity without the action of a ligand upon them (also referred to as 'constitutive activity'.)Receptor
agonists , antagonists and inverse agonists bind to the same receptor types. The pharmacological effect of an inverse agonist is measured as the negative value of the agonist primarily due to the historical findings of the already known agonist. Therefore, if the agonist has a positive value and the inverse agonist has a negative value, the antagonist for the receptor takes both the agonist and inverse agonist back to a neutral state.One particular example is
Ro15-4513 which is the inverse agonist of thebenzodiazepine class of drugs (such asalprazolam anddiazepam ). Ro15-4513 and the benzodiazepines both utilize the same GABA binding site on neurons, yet Ro15-4513 has the opposite effect, producing anxiety rather than the sedative effect of the benzodiazepines. [cite journal |author=Sieghart W |title=Pharmacology of benzodiazepine receptors: an update |journal=J Psychiatry Neurosci |volume=19 |issue=1 |pages=24–9 |year=1994 |pmid=8148363 |doi= |url=]References
ee also
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Agonist
*Receptor antagonist External links
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