RT Journal Article
SR Electronic
T1 High-Affinity Binding of [<sup>3</sup>H]5-Hydroxytryptamine to Brain Synaptosomal Membranes: Comparison with [<sup>3</sup>H]Lysergic Acid Diethylamide Binding
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 50
OP 59
VO 14
IS 1
A1 GILLES M. B. FILLION
A1 JEAN-CLAUDE ROUSSELLE
A1 MARIE-PAULE FILLION
A1 DOMINIQUE M. BEAUDOIN
A1 MICHAEL R. GOINY
A1 JEAN-MICHEL DENIAU
A1 JOSEPH J. JACOB
YR 1978
UL http://molpharm.aspetjournals.org/content/14/1/50.abstract
AB [3H]5-Hydroxytryptamine ([3H]5-HT) binds to crude brain membrane preparations at two different sites (Kd = 1-3 nM and 10-30 nM). These two sites are present in a limited number as saturable populations and selectively bind 5-HT and related structures. In the same crude membrane preparations, lysergic acid diethylamide (LSD) also binds at two different sites (Kd = 3-4 nM and 20-30 nM). 5-HT binding is found mostly in fractions enriched in synaptosomal and microsomal membranes; fractions rich in mitochondria or in synaptic vesicles have a low binding capacity. The two serotoninergic sites are physically separable; only high-affinity binding sites are found on purified synaptosomal membranes, whereas both types of sites are present in fractions enriched in microsomal membranes. The interaction between LSD and 5-HT shows that high-affinity binding sites for 5-HT are not identical with those for LSD, since the inhibition of binding of one substance by the other is complex. ACKNOWLEDGMENTS This investigation was supported in part by "Direction des Recherches et Moyens d'Essais (Contract No. 76/507) and Centre National de la Recherche Scientifique (A.T.P. No. 1803). We wish to thank Dr. Bocquet R., veterinaire inspecteur en chef, for his kind help in supplying horse brains.