Fig. 11. Intracellular Ca²⁺ concentration of sperm after SZP-induced acrosome reaction. Capacitated spermatozoa (CSP) (10⁷) were incubated with 1 µM of Ca²⁺-binding dye Fura 2-AM at 37°C for 40 minutes and was incubated with SZP. The fluorescence pattern was subsequently measured. (A) a, CSP + SZP; b, CSP + anti-PiN adsorbed with PiN + SZP; c, (CSP + anti-PiN) + SZP; d, (CSP + anti-MuN) + SZP; e, CSP + SZP adsorbed with PiN; f, CSP + SZP adsorbed with MuN. (B) For microscopic estimation, the number of Fura 2-AM-positive sperm was scored under a Nikon Optiphot fluorescence microscope. a, CSP, b, CSP + SZP, c, (CSP + anti-PiN) + SZP, d, (CSP + anti-MuN) + SZP.