Pharmacological characterization of serotonin-O-carboxymethyl-glycyl-tyrosinamide, a new selective indolic ligand for 5-hydroxytryptamine (5-HT)1B and 5-HT1D binding sites.
The affinity of a new serotonin (S) derivative, serotonin-O-carboxymethyl-glycyl-tyrosinamide (S-CM-GTNH2), for the various 5-hydroxytryptamine (5-HT)1 receptor subtypes was tested using quantitative autoradiography on rat and guinea pig brain sections. In the rat, S-CM-GTNH2 is 57 and 24 times more potent at 5-HT1B sites (IC50 = 28 nM) than at 5-HT1A (IC50 = 1600 nM) and 5-HT1C sites (IC50 = 670 nM), respectively. In the guinea pig, the affinity of S-CM-GTNH2 for 5-HT1D sites (IC50 = 67 nM) is 21 times higher than at 5-HT1A sites (IC50 = 1400 nM). S-CM-GTNH2 shows a low affinity (less than 10 microM) for 5-HT2 and 5-HT3 binding sites. This new ligand is therefore highly specific for 5-HT1B and 5-HT1D binding sites and can be used to further characterize the involvement of these subtypes in physiological studies focusing particularly on behavioral effects.
Boulenguez
P
P
Centre National de la Recherche Scientifique Laboratoire de Neurobiologie, Marseille, France.
Chauveau
J
J
Segu
L
L
Morel
A
A
Delaage
M
M
Lanoir
J
J
D000818:Animals; D001665:Binding Sites; D001921:Brain / Q000378:metabolism / Q000648:ultrastructure; D004151:Dipeptides / Q000378:metabolism / Q000494:pharmacology*; D004873:Ergolines / Q000378:metabolism; D006168:Guinea Pigs; D008297:Male; D008566:Membranes / Q000378:metabolism / Q000648:ultrastructure; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000145:classification / Q000378:metabolism*; D012701:Serotonin / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D012702:Serotonin Antagonists / Q000378:metabolism; D014316:Tritium
D004151:Dipeptides; D004873:Ergolines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D014316:Tritium; C072128:serotonin-O-carboxymethyl-Gly-Tyr; D012701:Serotonin; C031649:mesulergine