Fig. 3.

Type I collagenase treatment did not result in spontaneous capacitation or acrosome reaction. A Sperm capacitation and acrosome integrity accessed by tyrosine phosphorylated proteins and the presence of outer acrosome-specific lectin peanut agglutinin (PNA). Spermatozoon was considered capacitated when distinct tyrosine phosphorylation staining was observed at sperm tail (A1, A2, indicated with white arrow heads). Sperm acrosome was considered intact when homogeneous PNA staining could be observed at the anterior area of the sperm head (A3, marked with white arrow heads). Acrosome reacting/reacted spermatozoon showed a ring-like staining pattern at its post-equatorial region (A4, marked with arrow heads). B-C No significant differences on sperm capacitation and acrosome reaction rates were observed between control and 0.1% type I collagenase-treated group; N.S: not significantly different. At least 200 sperm cells were evaluated in each sample. Data were analyzed from 16 ejaculates from 4 individuals. Fifty micrograms of total protein was loaded onto each lane for immunoblotting experiment