Figure 5.
Pharmacological profile of the zebrafish CACNA1Ab P/Q-type calcium channel expressed in HEK293T cells. A, Representative recordings showing comparison of the block by 1 μm ω-conotoxin GVIA in 5 mm (filled symbols) and 10 mm (open symbols) Ba2+. The block is represented by the time-dependent reduction from preblock peak current amplitude. Each time point was taken at 5 s interval. The time of pressure application is indicated in each divalent concentration by the horizontal bars. The inset shows the Ba2+ current recorded preapplication (dark trace) and postapplication (light trace) of ω-conotoxin GVIA. The test voltage steps corresponded to +10 mV from a holding potential of −80 mV. B, The block by 1 μm ω-conotoxin MVIIC shown in the same manner as A. C, The block by 2 μm ω-agatoxin IVA is shown in the same manner as A. D, Comparison of the current block by different toxins. Average percentage of block and n value (in parentheses) for each condition are shown.