TY - JOUR T1 - A Common Basis for Inhibition of Nucleoside Transport by Dipyridamole and Nitrobenzylthioinosine? JF - Molecular Pharmacology JO - Mol Pharmacol SP - 40 LP - 44 VL - 18 IS - 1 AU - ALAN R. P. PATERSON AU - EDA Y. LAU AU - EWA DAHLIG AU - CAROL E. CASS Y1 - 1980/07/01 UR - http://molpharm.aspetjournals.org/content/18/1/40.abstract N2 - Transport of uridine by monolayer cultures of HeLa cells was inhibited by nitrobenzylthioinosine, dipyridamole, and lidoflazine. Biphasic concentration-effect curves were obtained for inhibition of nucleoside transport by nitrobenzylthioinosine, but not for inhibition by dipyridamole. Dipyridamole and lidoflazine interfered with high-affinity binding of [3H]nitrobenzylthioinosine to HeLa cells in an apparently competitive fashion; values of 1, 30, and 300 nM were obtained for dissociation constants, respectively, for nitrobenzylthioinosine, dipyridamole, and lidoflazine. The apparent competition with nitrobenzylthioinosine at the latter’s high-affinity binding sites suggests that dipyridamole and lidoflazine inhibit nucleoside transport by interaction with these sites. ER -