Preconditioning of sperm with sublethal nitrosative stress: a novel approach to improve frozen–thawed sperm function

Research question Can sublethal stress induced by nitric oxide on fresh human spermatozoa protect the functional properties of post–thaw human spermatozoa? Design Semen samples were obtained from 46 donors. Twenty semen samples were used to determine toxicity level of nitric oxide by incubation of semen with different concentrations of nitric oxide (0.01 to 400 μM). Then, 26 semen samples were cryopreserved with optimized ranges of nitric oxide:...