High-affinity 3H-serotonin binding to caudate: inhibition by hallucinogens and serotoninergic drugs.
The specific binding of 3H-serotonin to calf caudate homogenate was studied. The dissociation constant was 2nM and the number of specific sites was 14fmoles/mg protein. Of many drugs tested, inhibition of specific 3H-serotonin binding occurred almost exclusively with serotonin agonists and antagonists. The concentrations for 50% inhibition of 3H-serotonin binding by serotonergic agonists follow: bufotenin, 6nM; 5-methoxytryptamine, 12 nM; psilocin, 35nM; dimethyltryptamine, 220 nM; and tryptamine, 270 nM. The concentrations for the antagonists were: LSD 9.5 nM; methysergide 16nM and metergoline 25nM.
D000818:Animals; D001921:Brain / Q000378:metabolism; D002417:Cattle; D002421:Caudate Nucleus / Q000187:drug effects / Q000378:metabolism*; D006213:Hallucinogens / Q000494:pharmacology*; D066298:In Vitro Techniques; D007700:Kinetics; D008566:Membranes / Q000378:metabolism; D011985:Receptors, Serotonin / Q000187:drug effects / Q000378:metabolism*; D012701:Serotonin / Q000502:physiology*
D006213:Hallucinogens; D011985:Receptors, Serotonin; D012701:Serotonin