Study of zinc in protecting sperm from sodium nitroprusside damage

OBJECTIVE: To study the function of zinc in preventing human sperm from being damaged by sodium nitroprusside (SNP), an external NO donor. METHODS: Analyses were made of the function of zinc in protecting sperm from being influenced by SNP in such aspects as sperm motility, head-tail connection and the breakage of sperm DNA chain by using phase-contrast microscope and single cell gel electrophoresis (SCGE). RESULTS: Sperm motility was obviously inhibited by SNP. The percentage of comet cells increased significantly but the stability of sperm head-tail connection decreased. Zinc could promote sperm motility, protect the DNA chain and prevent the sperm head-tail connection from breaking. CONCLUSION: Zinc can protect sperm from being damaged by NO. Its mechanism may be related to the mercaptol group of sperm chromatin.