The 5-HT3B subunit confers reduced sensitivity to picrotoxin when co-expressed with the 5-HT3A receptor.
There are currently no known agents that display selectivity between homomeric 5-hydroxytryptamine type 3A (5-HT3A) and heteromeric 5-HT3A/3B receptors. In the present study, we show that the CNS convulsant picrotoxin selectively interacts with 5-HT3A receptors. In whole-cell patch clamp recordings, the inhibitory effect of PTX was reduced 100-fold in heteromeric mouse 5-HT3A/3B receptors, compared to homomeric 5-HT3A receptors. Picrotoxin should prove to be a useful probe for determining the presence of homomeric vs. heteromeric 5-HT3 receptors in both native tissue and recombinant receptor preparations.
Das
Paromita
P
Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA.
Dillon
Glenn H
GH
D000818:Animals; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D004361:Drug Tolerance / Q000235:genetics; D018756:GABA Antagonists / Q000494:pharmacology*; D006801:Humans; D015640:Ion Channel Gating / Q000187:drug effects / Q000235:genetics; D008024:Ligands; D051379:Mice; D010852:Picrotoxin / Q000494:pharmacology*; D021122:Protein Subunits / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D044406:Receptors, Serotonin, 5-HT3 / Q000235:genetics / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism / Q000494:pharmacology; D058831:Serotonin 5-HT3 Receptor Antagonists; D009435:Synaptic Transmission / Q000187:drug effects / Q000235:genetics
D018756:GABA Antagonists; D008024:Ligands; D010852:Picrotoxin; D021122:Protein Subunits; D044406:Receptors, Serotonin, 5-HT3; D012701:Serotonin; D058831:Serotonin 5-HT3 Receptor Antagonists