The comparison of DMR signals induced by P2Y agonists, each at its EC100, of confluent HEK293 cells cultured on four different surfaces (TCT and fibronectin-, collagen IV-, and gelatin-coated biosensor surfaces). (a) ATP; (b) 2-MeSATP; (c) ADP; (d) ATPγS; (e) UTP; (f ) UTPγS; and (g) UDP. The concentration was 2, 2, 100, 10, 16, 16, and 16 μM for 2-MeSATP, ADP, UDP, UTPγS, ATPγS, ATP, and UTP, respectively. Data presented are means±SEM of eight replicate wells (n=3).