RESUMO
<p><b>OBJECTIVE</b>To investigate the effect of Inonotus obliquus polysaccharides on testicular injury induced by exposure to high power microwave (HPM) in rats.</p><p><b>METHODS</b>A total of 30 male Wistar rats were randomly divided into 5 groups, i.e., the normal control group, the microwave radiation model group, the treatment group, the new microwave radiation model group, and the prevention group, 6 in each group. All rats, except those in the normal control group, were exposed to microwave at an average power density of 200 mW/cm2 for 6 min. Rats in the control group and the model group were administered with normal saline by gastrogavage, once a day. Rats in the treatment group and the prevention group were given with Inonotus obliquus polysaccharides by gastrogavage, 2 mL each time (400 mg/kg body weight), once a day. All rats were sacrificed on the 11th day.The sperm density and the rate of sperm deformity were determined. Pathological changes of testis were observed by light microscope and transmission electron microscope.</p><p><b>RESULTS</b>Short-term HPM irradiation could significantly reduce the sperm density and increase the sperm deformity rate (P < 0.05). Meanwhile, obvious pathological changes of testes occurred. Compared with the two model groups, the sperm density increased and the sperm deformity rate decreased in the treatment group and the prevention group (P < 0.05). Under the light microscope, injuries of spermatogenic cells and stromal cells, as well as vascular dilatation and congestion were obviously alleviated in the treatment group and the prevention group. Mitochondrial swelling and endoplasmic reticulum expansion shown by ultrastructural observation were also significantly alleviated. Of them, injuries of spermatogenic cells and inflammation response were milder in the treatment group than in the prevention group.</p><p><b>CONCLUSIONS</b>Inonotus obliquus polysaccharides had significant protective effect on microwave radiation induced testicular injury. Better effect was obtained by therapeutic medication than preventive medication.</p>