Methods
The expression and the localization of dynamin in the human testis, epididymis and mature spermatozoa were determined through the application of immunofluorescence, immunoblotting and/or electron microscopy. Human semen samples were fractionated via density gradient centrifugation and the resultant populations of good and poor quality spermatozoa were induced to capacitate and acrosome react in the presence or absence of selective dynamin inhibitors. The acrosome integrity of live spermatozoa was subsequently assessed via the use of fluorescently conjugated Arachis hypogea lectin (PNA). The influence of dynamin phosphorylation and the regulatory kinase(s) responsible for this modification in human spermatozoa were also assessed via the use of in situ proximity ligation assays and pharmacological inhibition. In all experiments, ≥100 spermatozoa were assessed/treatment group and all graphical data are presented as the mean values ± SEM, with statistical significance being determined by ANOVA. Main