Sandbox 77: Difference between revisions

5-HT3 antagonists have been predominantly used as an antiemetic drug in relieving treating symptoms such as nausea and vomiting for a cancer patient receiving chemotherapy. Three high affinity antagonist often used are granisetron, tropisteron and ondansetron. The common structure shared among 5-HT3 antagonists contains an amine with an aromatic ring system and a carbonyl group. <ref name = "two" /> Experimental homology modeling suggests that 5-HT3 antagonists have aromatic rings that form π-π interactions with the tyrosine, Y143 and tryptophan, W183, side chains of the 5-HT3 receptor. It is also theorized that the antagonist contain carbonyl groups which accept hydrogen bonds from serine, S227, side chain of the 5-HT3 receptor.<ref>Maksay G, Zsolt B, Miklós S. ''Binding Interactions of Antagonists with 5‐Hydroxytryptamine 3A Receptor Models.'' Journal of Receptors and Signal Transduction 23.2-3 (2003): 255-70. [http://www.tandfonline.com/doi/full/10.1081/RRS-120025568 DOI:10.1081/RRS-120025568]</ref> 5-HT3 antagonists have a wide variety of uses such as treating nausea, vomiting, irritable bowel syndrome and mood disorders. During the binding of granisteron to the 5-HT3 receptor, the aromatic rings sit within W183 and Y234 and an azabicyclic ring within W90 and F226 of the binding pocket.<ref name = "two" /> Once a 5-HT3 antagonist has bound to a 5-HT3 receptor, serotonin binding is inhibited.<ref>Brunton LL, Lazo JS, Parker KL. (2006). Goddman & Gilman's The Pharmacological Basis of Therapeutics. New York: McGraw-Hill. pp. 1000–3. ISBN 978-0-07-142280-2.</ref>