Figure 10.

Block by α-conotoxin EI of zebrafish muscle nAChRs expressed in X. laevis oocytes. The block of I_ACh by conotoxin was assessed as described in Figure 7. Plotted are the concentration–response curves for the block by α-EI of αβδ (open squares), αβδγ (open circles), and αβδε (closed circles) nAChRs. Each data point represents mean ± S.E. (n = 3–5). (See Table 2 for IC₅₀s.) Inset shows example I_ACh traces from an oocyte expressing αβδε nAChRs before and following a 5-min. exposure to 1 μM α-EI; duration of each trace is 5 s. The block by α-EI is only slowly reversible.