OBJECTIVETo investigate the effects of different concentrations of Morinda Officialis How (MOH) extracts on microwave radiation-induced injury to the spermatogenic function of male rats.

METHODSForty 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.

RESULTSCompared 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.

CONCLUSIONBoth aqueous and alcohol extracts of MOH can promote spermatogenesis and repair of reproductive injury induced by microwave radiation.