RESUMO
<p><b>OBJECTIVE</b>To investigate the effects of different concentrations of Morinda Officialis How (MOH) extracts on microwave radiation-induced injury to the spermatogenic function of male rats.</p><p><b>METHODS</b>Forty SD male rats were equally divided into four groups: control, microwave injury model, aqueous extract of MOH treatment, and alcohol extract of MOH treatment. Models of microwave-induced injury were made by exposing the rats to microwave radiation from a microwave signal generator (900 MHz 1.0 W) at 218 microm/cm2, 12 h/d, for 2 weeks. The model rats of the two treatment groups were intragastrically given aqueous extract and alcohol extract of MOH, respectively, both at 20 g per kg per day for 2 weeks. Then we observed the growth, capture incubation period (CIP), capture times (CT), changes in testicular and epididymal weight and morphology, sperm concentration and malformation, and levels of serum testosterone.</p><p><b>RESULTS</b>Compared with the controls, the rats of the model group showed a slightly reduced body weight, markedly prolonged CIP and decreased CT (P < 0.05), significantly reduced sperm concentration (P < 0.05) and remarkably in- creased sperm malformation (P < 0.05), but no statistically significant differences in the testosterone level. The two treatment groups exhibited obviously decreased body weight, CIP and sperm malformation compared with the control group (P < 0.05) but markedly increased CT, sperm concentration and testosterone level as compared with the models (P < 0.05). The microwave radiation-induced testis injury was repaired perfectly in the two treatment groups, the epididymal ducts filled with sperm and cast-off cells.</p><p><b>CONCLUSION</b>Both aqueous and alcohol extracts of MOH can promote spermatogenesis and repair of reproductive injury induced by microwave radiation.</p>