%0 Journal Article %1 Merighi2002a %A Merighi, S. %A Varani, K. %A Gessi, S. %A Klotz, K. N. %A Leung, E. %A Baraldi, P. G. %A Borea, P. A. %D 2002 %J Biochem Pharmacol %K & A3 Adenosine Adenosine/*analogs Animals CHO Compounds/pharmacology Cricetinae Cultured Humans Kinetics P1/agonists/antagonists Phenylurea Purinergic Thermodynamics Transfection Triazoles/pharmacology derivatives/pharmacology inhibitors/chemistry/*metabolism Receptor Cell %N 2 %P 157-61 %T Binding thermodynamics at the human A(3) adenosine receptor %U http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11841789 %V 63 %X The thermodynamic parameters DeltaG , DeltaH and DeltaS of the binding equilibrium of six adenosine receptor agonists and five antagonists at adenosine A(3) receptors were determined by means of affinity measurements at six different temperatures (4, 10, 15, 20, 25 and 30) and van't Hoff plots were constructed. Affinity constants were measured on Chinese hamster ovary (CHO) cells transfected with the human A(3) receptors by inhibition assays of the binding of the selective A(3) antagonist 3HMRE 3008F20. van't Hoff plots were linear for agonists and antagonists in the temperature range 4-30 degree. Their thermodynamic parameters fall in the ranges 21 < or = DeltaH < or = 67kJmol(-1) and 208 < or = DeltaS < or =410 J(Kmol)(-1) for agonists and -52 < or = DeltaH < or = -9 kJmol(-1) and 16 < or = DeltaS < or =81 J(K/mol)(-1) for antagonists, showing that agonist binding is always totally entropy-driven while antagonist binding is enthalpy- and entropy-driven. The results are discussed with the aim of obtaining new details on the nature of the forces driving the A(3) binding at a molecular level.

@article{Merighi2002a, abstract = {The thermodynamic parameters DeltaG , DeltaH and DeltaS of the binding equilibrium of six adenosine receptor agonists and five antagonists at adenosine A(3) receptors were determined by means of affinity measurements at six different temperatures (4, 10, 15, 20, 25 and 30) and van't Hoff plots were constructed. Affinity constants were measured on Chinese hamster ovary (CHO) cells transfected with the human A(3) receptors by inhibition assays of the binding of the selective A(3) antagonist [3H]MRE 3008F20. van't Hoff plots were linear for agonists and antagonists in the temperature range 4-30 degree. Their thermodynamic parameters fall in the ranges 21 < or = DeltaH < or = 67kJmol(-1) and 208 < or = DeltaS < or =410 J(Kmol)(-1) for agonists and -52 < or = DeltaH < or = -9 kJmol(-1) and 16 < or = DeltaS < or =81 J(K/mol)(-1) for antagonists, showing that agonist binding is always totally entropy-driven while antagonist binding is enthalpy- and entropy-driven. The results are discussed with the aim of obtaining new details on the nature of the forces driving the A(3) binding at a molecular level.}, added-at = {2010-12-14T18:12:02.000+0100}, author = {Merighi, S. and Varani, K. and Gessi, S. and Klotz, K. N. and Leung, E. and Baraldi, P. G. and Borea, P. A.}, biburl = {https://www.bibsonomy.org/bibtex/2cd40fc70e49ad867deb8c4de1ece7c5d/pharmawuerz}, endnotereftype = {Journal Article}, interhash = {1b5554ca55e9da7f41f6e929b84bbed9}, intrahash = {cd40fc70e49ad867deb8c4de1ece7c5d}, issn = {0006-2952 (Print) 0006-2952 (Linking)}, journal = {Biochem Pharmacol}, keywords = {& A3 Adenosine Adenosine/*analogs Animals CHO Compounds/pharmacology Cricetinae Cultured Humans Kinetics P1/agonists/antagonists Phenylurea Purinergic Thermodynamics Transfection Triazoles/pharmacology derivatives/pharmacology inhibitors/chemistry/*metabolism Receptor Cell}, month = {Jan 15}, note = {Merighi, Stefania Varani, Katia Gessi, Stefania Klotz, Karl Norbert Leung, Edward Baraldi, Pier Giovanni Borea, Pier Andrea England Biochemical pharmacology Biochem Pharmacol. 2002 Jan 15;63(2):157-61.}, number = 2, pages = {157-61}, shorttitle = {Binding thermodynamics at the human A(3) adenosine receptor}, timestamp = {2010-12-14T18:20:50.000+0100}, title = {Binding thermodynamics at the human A(3) adenosine receptor}, url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11841789}, volume = 63, year = 2002 }