Fig. 3. Effects of CaM antagonists on tyrosine phosphorylation of the mouse sperm components. Spermatozoa were incubated at 37°C for 90 minutes in EKRB medium supplemented with 3 mg BSA/ml (A) or 1 mM methyl-ß-cyclodextrin (B) in the absence (control) or presence of different concentrations (µM) of CaM antagonists (compound 48/80, 2; W13, 1.58; CBD, 0.16). Tyrosine phosphorylation was revealed as above. The figure shows data of a representative experiment. Similar results were obtained in two other experiments. A slight variation in phosphorylated proteins around 80 kDa in this figure (compare A versus B) is probably due to different running conditions.