FIG. 7.
Sorbitol can substitute for glucose or fructose in capacitating media. Sperm were incubated in noncapacitating medium (ModW with monosaccharide), regular capacitating medium (ModW with monosaccharide, sodium bicarbonate, 2-OH-β-CD [labeled as 2-OH-b-CD]), or regular capacitating medium lacking monosaccharide for 1.5 h. A) Sperm proteins were extracted, subjected to SDS-PAGE, immunoblotted, and probed with anti-phosphotyrosine antibody. This experiment was repeated twice with similar results. Numbers to the left of the figure represent molecular weights of standard proteins (×10−3). B) Hyperactive motility was measured among the different groups above. Increased hyperactive motility was normalized by subtracting baseline hyperactive motility (at time point 0). The sperm were incubated in noncapacitating media (with glucose [a], fructose [b], sorbitol [c]) or in capacitating medium (with no added sugar [d], glucose [e], fructose [f], sorbitol [g]) (n = 3).