Objective: This study was aimed to disclose whether the VLA-5 integrin on human sperm membrane takes part in the activation of human spermatozoa.
Methods: Fluo-3/AM was coincubated with human spermatozoa. The change of intracellular calcium([Ca2+]i) was determined by flow cytometry when human sperms were exposed to Fibronectin(Fn) as the specific ligand of integrin VLA-5. Human sperm acrosome reaction(AR) rate was evaluated by triple-stain technique.
Results: Fn significantly raised the AR rate (P < 0.05) and the level of [Ca2+]i (P < 0.01) in the spermatozoa of fertile men. But there was no significant rise in the level of [Ca2+]i in the spermatozoa of infertile men.
Conclusion: The VLA-5 integrin on human sperm membrane plays a role in the activation of sperm.