Temperature-sensitive high affinity [3H]serotonin binding: characterization and effects of antidepressant treatment.
Characterization of temperature-sensitive [3H]serotonin (5-HT) binding sites (1 and 4 nM Kd sites) revealed complex inhibition by neuroleptics and serotonin antagonists. There was no simple correlation with affinities for S1 and S2 receptors. In vivo pretreatment (48 h before) with mianserin did not alter Bmax or Kd for the 1 nM Kd [3H]5-HT site, although [3H]ketanserin (S2) densities were decreased by 50%. This suggested that possible S2 components of [3H]5-HT binding must be negligeable, even though ketanserin competed with high affinity (IC50 = 3 nM) for a portion of the 1 nM Kd [3H]5-HT site. Low concentrations of mianserin inhibited the 1 nM Kd [3H]5-HT site in a non-competitive manner, as shown by a decrease in Bmax with no change in Kd after in vitro incubation. The complex inhibition data may therefore represent indirect interactions through another site.
D000818:Animals; D001667:Binding, Competitive; D002540:Cerebral Cortex / Q000378:metabolism*; D007650:Ketanserin; D007700:Kinetics; D008297:Male; D008803:Mianserin / Q000494:pharmacology; D010880:Piperidines / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000378:metabolism; D013696:Temperature; D014316:Tritium
D010880:Piperidines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D014316:Tritium; D008803:Mianserin; D007650:Ketanserin