OBJECTIVESTo analyze the changes of movement function and viability in human spermatozoa induced by reactive oxygen species(ROS), and to prove whether ROS were one of the causes of the movement dysfunction of spermatozoa.

METHODSSpermatozoa with normal physiological functions selected from semen samples by Percoll gradient centrifugation technique were regarded as normal sperm models. ROS were generated by hypoxanthine-xanthine oxidase system and then incubated with normal sperm models under aerobic environment. After model spermatozoa were incubated with ROS, movement parameters of spermatozoa were analyzed by computer-assisted semen analysis (CASA) system.

RESULTSCompared with the control group, after model spermatozoa were incubated with ROS for 30 minutes, motility, curvilinear velocity(VCL), straight line velocity (VSL) and average path velocity (VAP) of the spermatozoa were significantly decreased (P < 0.001), but amplitude of lateral head displacement (ALH) was insignificant (P > 0.05). When incubated with ROS for 60 minutes, spermatozoa almost lost movement function and all movement parameters of spermatozoa inclined to zero.

CONCLUSIONSWhen normal spermatozoa were incubated with ROS, movement functions of sperm were decreased. It was demonstrated that ROS were one of the causes of the movement dysfunction of spermatozoa.