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+--- Thread: ondansetron???? - katy2011 (/showthread.php?tid=631704)
ondansetron???? - katy2011 - ArchivalUser - 11-16-2011
how Ondansetron acts???
i know it is a 5-HT3 antagonist...used as anti emetic.. but what is the exact mechanism of action..(second messeng...ligand???).please if anyone can answer...thanks
0 - ArchivalUser - 11-16-2011
As you know there are 7 receptor subtypes of Serotonin.
5HT3(found in area postrema,peripheral sensory and enteric nerves) is the only one that is coupled directly to an ion channel/...5-HT3 receptors are unique among the families of 5-HT receptors, in that they are nonselective Na+/K+ ion channel receptors.)
MOA.....activatation opens ion channels (not secound messangers),and other 6 receptor subtypes are all G-protein coupled.(Buspirone,Sumatriptan,Olanzapine,Cproheptadine)
0 - ArchivalUser - 11-16-2011
ok thanks maryam...it was a kaplan q and i was confused..good luck with your preparation