Figure 4: Distribution of (A) cholesterol, (B) ganglioside GM1, and (C) total pro- teins in the fractions obtained by 2 h ultracentrifugation of Triton X-100 lysates in an OptiprepTM gradient of fresh (■), control (■), capacitated (■), and acrosome reacted (■) samples. Media ± SEM (n=5). Significant differences between fresh and control, capacitated or acrosome reacted sperm samples in the same frac- tion: *P<0.05; ** P<0.01; *** P<0.001