title: The preferential dopamine D3 receptor ligand, (+)-UH232, is a partial agonist.
abstract: In a NG 108 15 hybrid cell line stably expressing a recombinant dopamine D3 receptor, (+)-UH 232 (cis-(+)-1S,2R)-5-methoxy-1-methyl-2-(di-n- propylamino)tetralin), a partially selective D3 receptor ligand, stimulates mitogenesis, as measured by incorporation of [3H]thymidine, with an EC50 of 7.6 nM and a maximal increase corresponding to 23% of the response elicited by quinpirole, a full agonist. This effect was antagonised by nafadotride, a D3 receptor-selective antagonist. (+)-UH 232 also antagonised quinpirole-induced mitogenesis with a Ki value of 9.4 nM. (+)-UH 232 (1 microM) inhibited by 22% the forskolin-induced accumulation of cAMP, whilst the inhibition by quinpirole (100 nM) was 53%. These results indicate that (+)-UH 232 is a partial agonist at the D3 receptor with an intrinsic activity of 0.2-0.4.
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000031:analogs & derivatives* / Q000494:pharmacology; D004873:Ergolines / Q000494:pharmacology; D006801:Humans; D006822:Hybrid Cells; D008934:Mitogens / Q000494:pharmacology; D019257:Quinpirole; D011954:Receptors, Dopamine / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D011994:Recombinant Proteins / Q000096:biosynthesis
chemical_list: C493593:DRD3 protein, human; D004873:Ergolines; D008934:Mitogens; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D011994:Recombinant Proteins; D019257:Quinpirole; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; C045971:UH 232