Figure 3.

Effects of mutations at E236 on dTC, chondocurarine, and 12′-O-methylchondoocurine affinity. The concentration dependence of inhibition of [³H]granisetron binding to WT, E236Q, and E236N 5-HT₃Rs by dTC (•), chondocurarine (▴), and 12′-OMCC (■) are shown. Each data point represents the mean ± SE of three determinations. The solid curves are drawn according to Eq. 1 using log(IC₅₀) values of −6.90 (WT, dTC), −6.33 (WT, chondocurarine), −5.25 (WT,12′-OMCC), −5.81 (E236Q, dTC), −5.15 (E236Q, chondocurarine), −4.14 (E236Q,12′-OMCC), −5.34 (E236N, dTC), −4.91 (E236N, chondocurarine), and −4.76 (E236N,12′-OMCC).