Figure 1.

Reduction of sperm motility and functional CatSper channels expression in the spermatozoa of idiopathic asthenozoospermic (iAZS) patients. (A-B) Sperm motility including rapid progressive motility (grade A) sperm (A) and progressive motility (grade A+B) sperm (B) in AZS patients (n = 35) and healthy subjects (HS) (n = 35). (C-G) CatSper mRNA (C) and protein (from CatSper1 to CatSper4) (D-G) expression in the spermatozoa of AZS patients and HS controls (n = 3-6 tested subjects per group). (H) Representative fluorescence images from Fura-2 loaded human sperm before and after 30 mM NH₄Cl treatment in different groups as indicated. Arrows indicate the [Ca²⁺]_i fluorescent signals of the sperm in response to NH₄Cl treatment. Scale bar = 10 μm. (I) Representative single sperm fluorescence traces. (J) Changes in normalized [Ca²⁺]_i fluorescent signals of all tested sperm. (K) Summary plot of normalized [Ca²⁺]_i fluorescent signals of all tested sperm in response to NH₄Cl treatment (n = 32-39 spermatozoa from 4 to 6 tested subjects per group). All data are presented as mean ± SEM. ^*P < 0.05, ^**P < 0.01, ^***P < 0.001. Unpaired t test for (A)-(B), and (D)-(G); one-way ANOVA with Sidak's post-hoc test for (K).