Silvio Dionisotti

Learn More
We have characterized the in vitro pharmacological profile of the new potent and selective A2a adenosine receptor antagonist SCH 58261 [7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2, 4-triazolo[1,5-c]pyrimidine]. In binding studies on rat and bovine brain tissues, SCH 58261 showed affinity in the low nanomolar range at A2a adenosine striatal(More)
1. The present study describes the binding to rat striatal A2A adenosine receptors of the new potent and selective antagonist radioligand, [3H]-5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo[4,3-e]-1,2,4-triazol o [1,5-c] pyrimidine, [3H]-SCH 58261. 2. [3H]-SCH 58261 specific binding to rat striatal membranes ( > 90%) was saturable, reversible and dependent(More)
1. We have characterized the binding of the new potent and selective antagonist radioligand [3H]-5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo[4,3-e]-1,2,4-triazol o[1,5- c]pyrimidine, [3H]-SCH 58261, to human cloned A2A adenosine receptors. 2. In Chinese hamster ovary (CHO) cells transfected with the human cloned A2A receptor, [3H]-SCH 58261 specific(More)
Three structurally related non-xanthine compounds, CGS 15943, ZM 241385 and SCH 58261, are potent A2A adenosine receptor antagonists and have been used as tools in many pharmacological studies. We have now characterized their affinity and selectivity profile on human adenosine receptors stably transfected into either CHO cells (A1 and A2B receptors) or(More)
1. The present study describes the direct labelling of A2A adenosine receptors in human neutrophil membranes with the potent and selective antagonist radioligand, [3H]-5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo[4,3-e]-1,2,4 triazolo[l,5-c]pyrimidine, ([3H]-SCH 58261). In addition, both receptor affinity and potency of a number of adenosine receptor(More)
A series of pyrazolo[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine derivatives (10a-o,q,r), bearing alkyl and aralkyl chains on positions 7 and 8, were synthesized in the attempt to obtain potent and selective antagonists for the A(2A) adenosine receptor subtype. The compounds were tested in binding and functional assays to evaluate their potency for the A(2A)(More)
New A2A adenosine receptor antagonists in the series of pyrazolo[4, 3-e]-1,2,4-triazolo[1,5-c]pyrimidines, bearing oxygenated substituents on the phenylalkyl chains on the 7-position, have been synthesized. The compounds were tested in binding and functional assays to evaluate affinity, potency, and selectivity for rat A2A compared to rat A1 and human A3(More)
This study demonstrates quantification of A2A adenosine receptors (A2AAdoRs) in membranes prepared from porcine coronary arteries, porcine striatum, and PC12 cells. Radioligand binding assays were performed using the new selective A2AAdoR antagonist radioligand [3H]-5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo [4,3-epsilon]-1,2,4-triazolo[1,5-c)pyrimidine(More)
The inhibitory effects of several adenosine analogues, including the new A2-selective agonists 2-[p-(2-carboxyethyl)phenethylamino]-5′-N-ethylcarboxamido-adenosine (CGS 21680) and 2-hexynyl-5′-N-ethylcarbox-amidoadenosine (2-hexynyl-NECA), were investigated in vitro on human and rabbit platelet aggregation. The compounds examined inhibited ADP-induced(More)
We investigated the effects of the selective A1 adenosine receptor agonist 2-chloro-N6-cyclopentyladenosine (CCPA), the selective A2 adenosine agonists 2-hexynyl-5'-N-ethyl-carboxamidoadenosine(2-hexynyl-NECA) and 2-[p-(2-carboxyethyl)-phenethylamino]-5'-N-ethylcarboxamidoadenosi ne (CGS 21680), and the nonselective adenosine agonist(More)