Figure 4.

Effect of chromanol 293B on ion homeostasis during human sperm capacitation. (A) Intracellular K⁺ concentration ([K⁺]_i) was detected using the K⁺ fluorescence probe PBFI-AM. The fluorescence intensity was directly proportional to [K⁺]_i. (B) Human sperm membrane potential (V_m) was analyzed using the fluorescence probe DisC3(5). The fluorescence intensity was directly proportional to V_m. (C) Intracellular Ca²⁺ concentration ([Ca²⁺]_i) was detected using the Ca²⁺ fluorescence probe Fluo3-AM. The fluorescence intensity was directly proportional to [Ca²⁺]_i. (D) Intracellular Cl⁻ concentration ([Cl⁻]_i) was detected using the Cl⁻ fluorescence probe MQAE. The fluorescence intensity was inversely proportional to [Cl⁻]_i. (E) Intracellular pH (pH_i) was analyzed using the pH fluorescence probe BCECF-AM. The fluorescence intensity was directly proportional to pH_i. All the data were acquired at 3min intervals for 30min during capacitating incubation. After capacitation for 3h, the fluorescence signal was acquired again. Asterisks indicate the significant differences between samples and vehicle control at the same time point (^*p<0.05). The exact P value were provided in the supplementary data (Table S1). Values represent the means ± SEM of 3 experiments.