Figure 3.

Effect of Ca²⁺ channel blockers on the initiation of sperm motility. Semen was diluted in FPS (see Materials and Methods) containing Ca²⁺ channel blocker, 100 μM verapamil, nitrendipine, and flunarizine, 200 μM D-600; 2 μM ω-conotoxin GVIA, ω-conotoxin MVIIC, and ω-conotoxin SVIB, and incubated for 3 min, and then 5 μl of the sperm suspension was diluted in 50 μl of AS containing each blocker and sperm motility was measured. Five to ten times higher dose than the effective blocking dose (up to 50 μM) of nimodipine, PLTX-II, ω-agatoxin, calciludine, nifedipine, ω-conotoxin MVIIA, and waglorine had no inhibitory effect on sperm motility (data not shown). Control was taken in the absence of Ca²⁺ channel blocker. Bar represents mean ± SD (n = 5).