Characterization of the Functional Activity of Dopamine Ligands at Human Recombinant Dopamine D4 Receptors
Characterization of the Functional Activity of Dopamine Ligands at Human Recombinant Dopamine D4 Receptors
复制标题
人重组多巴胺 D4 受体上多巴胺配体功能活性的表征
作者：
C. Chabert;Catherine Cavegn;Alain Bernard;A. Mills
Abstract: The human D4 dopamine receptor has been expressed in Sf9 insect cells where it appears to couple to endogenous G proteins. Increased guanine nucleotide exchange to G proteins is a reflection of receptor activation and can be followed using a [35S]GTPγS binding assay. By measuring D4 receptor stimulation of [35S]‐GTPγS binding we have been able to characterize several dopaminergic compounds for their functional activity at this receptor. In Sf9 cells expressing the D4 receptor, dopamine, quinpirole, and dp‐2‐aminodihydroxy‐1,2,3,4‐tetrahydronaphthalene were all full agonists, whereas (−)‐apomorphine appeared to be a partial agonist. No increase in [35S]GTPγS binding was observed for noninfected cells or cells infected with an unrelated sequence. The quinpirole‐stimulated [35S]GTPγS binding could be inhibited by the antagonists clozapine, eticlopride, and haloperidol, and a Schild analysis of these data showed that all three compounds were acting as competitive antagonists of D4 receptors. The rank order of affinities derived from the Schild analysis correlated with that obtained from [3H]spiperone competition binding assays. In conclusion, we have shown that, using this assay system, it is possible to investigate functionally the pharmacology of a recombinant G protein‐coupled receptor in the absence of any information regarding the eventual second messenger pathways involved.
Sf9 昆虫细胞中人 m2 毒蕈碱胆碱能受体激动剂诱导的磷酸化和脱敏。
DOI：
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发表时间：
1992
期刊：
The Journal of biological chemistry
影响因子：
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作者：
Richardson,RM;Hosey,MM
通讯作者：
Hosey,MM
影响因子：
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作者：
J. Kane;G. Honigfeld;J. Singer;H. Meltzer
通讯作者：
J. Kane;G. Honigfeld;J. Singer;H. Meltzer