PT  - JOURNAL ARTICLE
AU  - DAVID R. BURT
AU  - IAN CREESE
AU  - SOLOMON H. SNYDER
TI  - Binding Interactions of Lysergic Acid Diethylamide and Related Agents with Dopamine Receptors in the Brain
DP  - 1976 Jul 01
TA  - Molecular Pharmacology
PG  - 631--638
VI  - 12
IP  - 4
4099  - http://molpharm.aspetjournals.org/content/12/4/631.short
4100  - http://molpharm.aspetjournals.org/content/12/4/631.full
SO  - Mol Pharmacol1976 Jul 01; 12
AB  - In most brain regions saturable binding of d-[3H]lysergic acid diethylamide ([3H]LSD) appears to involve postsynaptic serotonin receptors. In calf caudate, however, a portion of [3H]LSD binding involves postsynaptic dopamine receptors. Thus, in the hippocampus of calf brain, dopamine competes for [3H]LSD binding sites with a single low-affinity component, while in the caudate dopamine competition for [3H]LSD binding displays both high- and low-affinity components. The high-affinity component, accounting for 15-20% of [3H]LSD binding, displays a Ki value for dopamine of about 30 nM, similar to the KD for the binding of [3H]dopamine itself to postsynaptic dopamine receptors in the calf caudate. Addition of serotonin to the incubations increases the proportion of [3H]LSD binding in the caudate competed for by dopamine with high affinity, presumably by occupying serotonin receptors. d-LSD competes stereospecifically for [3H]dopamine binding in the caudate, consistent with the conclusion that LSD binds to dopamine receptors. Of numerous serotonin agonists and antagonists examined, several ergot alkaloids have high affinity for [3H]dopamine receptor binding in calf caudate, with Ki values similar to that of d-LSD. ACKNOWLEDGMENTS We thank Janet Ryan for excellent technical assistance.