[125I]Spiperone is not a useful ligand for studying the CHAPS solubilized dopamine D-2 receptor from rat striatum.
The interaction of [125I]spiperone and [3H]spiperone with CHAPS solubilized preparations of rat striatal tissue has been compared. Only about 15% of [125I]spiperone binding was displaced by sulpiride compared with about 67% of [3H]spiperone binding. In the presence of (+)-butaclamol the displacement of [125I]spiperone was twice that found with sulpiride suggesting an interaction with sites other than D-2 receptors. The specific binding of [125I]spiperone was not saturable within the maximum concentration range that could be employed and its affinity for soluble preparations was far lower than that of [3H]spiperone. Despite its very high specific activity [125I]spiperone offers no advantage over [3H]spiperone in the identification of dopamine receptors in soluble tissue preparations.
G J
GJ
Kilpatrick
P
P
Jenner
C D
CD
Marsden
D000818:Animals; D002069:Butaclamol / Q000494:pharmacology; D002090:Butyrophenones; D002793:Cholic Acids; D003342:Corpus Striatum / Q000187:drug effects*; D005260:Female; D066298:In Vitro Techniques; D007700:Kinetics; D008024:Ligands; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects*; D013134:Spiperone
D002090:Butyrophenones; D002793:Cholic Acids; D008024:Ligands; D011954:Receptors, Dopamine; D013134:Spiperone; D002069:Butaclamol; C028213:3-((3-cholamidopropyl)dimethylammonium)-1-propanesulfonate