TY - JOUR
T1 - Interaction of new, very potent non-nucleotide antagonists with Arg256 of the human platelet P2Y12 receptor
AU - Hoffmann, Kristina
AU - Baqi, Younis
AU - Morena, María Sol
AU - Glänzel, Markus
AU - Müller, Christa E.
AU - Von Kügelgen, Ivar
PY - 2009/11
Y1 - 2009/11
N2 - The P2Y12 receptor plays a crucial role in platelet aggregation. In the present study, we analyzed the properties of non-nucleotide antagonists at the recombinant human P2Y12 receptor and searched for amino acids involved in the molecular interaction. Receptor function was assessed by measuring the cAMP response element (CRE)-directed luciferase expression in Chinese hamster ovary cells. The cellular cAMP production was accelerated by forskolin; 2-methylthio-ADP was used to activate the wild-type P2Y12 receptor or mutant constructs. 2-Methylthio-ADP inhibited the CRE-dependent luciferase expression with an IC50 value of approximately 1 nM. The anthraquinone derivative reactive blue 2 used at increasing concentrations shifted the concentration-response curve of 2-methylthio-ADP to the right in a manner compatible with competitive antagonism (pA2 value, 7.4). Its analog, 1-amino-4-[4-phenylamino-3-sulfophenylamino]-9,10-dioxo-9,10- dihydroanthracene-2-sulfonate (PSB-0739), showed a markedly higher antagonistic potency with a pA2 value of 9.8. In cells expressing the R256A-mutant receptor, the potencies of both reactive blue 2 (apparent pKB, 5.9) and PSB-0739 (apparent pKB, 9.1) were decreased. The same was true for the pure reactive blue 2 meta- and para-isomers and for the ortho-isomer cibacron blue 3GA. In contrast, the analog, 1-amino-4-[4-anilino-phenylamino]-9, 10-dioxo-9,10-dihydroanthracene-2-sulfonate, lacking a sulfonic acid residue at ring D (PSB-0826), showed similar pKB values at wild-type (8.4) and R256A-mutant receptors (8.3). In summary, the results demonstrate that PSB-0739 is the most potent competitive nonnucleotide antagonist at the human P2Y 12 receptor described so far. The results also indicate that the sulfonic acid residue at ring D is involved in the interaction of antagonists derived from reactive blue 2 with the residue Arg256 of the human P2Y 12 receptor.
AB - The P2Y12 receptor plays a crucial role in platelet aggregation. In the present study, we analyzed the properties of non-nucleotide antagonists at the recombinant human P2Y12 receptor and searched for amino acids involved in the molecular interaction. Receptor function was assessed by measuring the cAMP response element (CRE)-directed luciferase expression in Chinese hamster ovary cells. The cellular cAMP production was accelerated by forskolin; 2-methylthio-ADP was used to activate the wild-type P2Y12 receptor or mutant constructs. 2-Methylthio-ADP inhibited the CRE-dependent luciferase expression with an IC50 value of approximately 1 nM. The anthraquinone derivative reactive blue 2 used at increasing concentrations shifted the concentration-response curve of 2-methylthio-ADP to the right in a manner compatible with competitive antagonism (pA2 value, 7.4). Its analog, 1-amino-4-[4-phenylamino-3-sulfophenylamino]-9,10-dioxo-9,10- dihydroanthracene-2-sulfonate (PSB-0739), showed a markedly higher antagonistic potency with a pA2 value of 9.8. In cells expressing the R256A-mutant receptor, the potencies of both reactive blue 2 (apparent pKB, 5.9) and PSB-0739 (apparent pKB, 9.1) were decreased. The same was true for the pure reactive blue 2 meta- and para-isomers and for the ortho-isomer cibacron blue 3GA. In contrast, the analog, 1-amino-4-[4-anilino-phenylamino]-9, 10-dioxo-9,10-dihydroanthracene-2-sulfonate, lacking a sulfonic acid residue at ring D (PSB-0826), showed similar pKB values at wild-type (8.4) and R256A-mutant receptors (8.3). In summary, the results demonstrate that PSB-0739 is the most potent competitive nonnucleotide antagonist at the human P2Y 12 receptor described so far. The results also indicate that the sulfonic acid residue at ring D is involved in the interaction of antagonists derived from reactive blue 2 with the residue Arg256 of the human P2Y 12 receptor.
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U2 - 10.1124/jpet.109.156687
DO - 10.1124/jpet.109.156687
M3 - Article
C2 - 19690189
AN - SCOPUS:70350449259
SN - 0022-3565
VL - 331
SP - 648
EP - 655
JO - Journal of Pharmacology and Experimental Therapeutics
JF - Journal of Pharmacology and Experimental Therapeutics
IS - 2
ER -