BACKGROUND: How to control the effect of oxygen-derived free radicals on development of cerebral injury and cerebral edema is a key factor for treating cerebral ischemia-reperfusion injury. OBJECTIVE: To observe and compare the protective effects, synergistic action and mechanisms of ultrashortwave (USW) and radix salviae miltiorrhizae (RSM) on the focal cerebral ischemia-reperfusion injuries in rats. DESIGN: Randomized controlled animal study. SETTING: Department of Rehabilitation Medicine, First Hospital affiliated to China Medical University. MATERIALS: A total of 160 healthy Wistar rats of both genders and aged 18-20 weeks weighing 250-300 g of clean grade were selected in this study. 5 mL/ampoule RSM injection fluid was produced by the First Pharmaceutical Corporation of Shanghai (batch number: 011019, 0.01 mL/g). The USW therapeutic device was produced by Shanghai Electronic Device Factory with the frequency of 40.68 MHz and the maximal export power of 40 W. The first channel of power after modulation was 11 W. METHODS: The experiment was carried out in the Rehabilitation Medicine Department of the First Hospital affiliated to China Medical University from May 2002 to January 2003. Focal ischemia-reperfusion model was established in rats by reversible right middle cerebral artery occlusion with filament. Right cerebral ischemia was for 2 hours and then with 24 hours reperfusion. The scores of neurological deficits were evaluated by 0 to 4 scales. After surgery, 64 successful rats models were divided into four groups according to digital table: control group, USW group, RSM group and RSM + USW group with 16 cases in each group. Rats in control group were intraperitoneally injected with the same volume of saline (0.1 mL/g); rats in USW group were given small dosage of USW on head for 10 minutes at 6 hours after reperfusion; rats in RSM group were intraperitoneally injected with 0.01 mL/g RSM solution at 30 minutes before reperfusion; rats in RSM + USW group were intraperitoneally injected with 0.01 mL/g RSM parenteral solution at 30 minutes before reperfusion and given small dosage of USW on head for 10 minutes once at 6 hours after reperfusion; sixteen rats in sham operation group did not receive any treatment. All 80 rats were taken brains at 24 hours after reperfusion to measure wet and dry weights to calculate water content: Cerebral water content (%) = (1-dry/wet weight) × 100%. Superoxide dismutase (SOD) activity was measured by hydroxylamine method and malondialdehyde (MDA) content was measured by TBA photometric method. MAIN OUTCOME MEASURES: Cerebral water content, SOD activity and MDA content. RESULTS: All 160 rats except 80 failing in modeling were involved in the final analysis. ① The cerebral water content of left hemisphere made no significant difference (P > 0.05). The cerebral water content of right hemisphere in the control group and the three treatment groups was obviously higher than that of the sham operation group [(81.26±0.77)%, (79.74±0.68)%, (79.76±0.81)%, (79.61±0.79)%, (77.43±0.61)%, P < 0.05]. The cerebral water content of right hemisphere in the three treatment groups was obviously lower than that of the control group (P < 0.05). There was no significant difference among the three treatment groups (P > 0.05). ② Compared with the control group, SOD activity (right) of the control group decreased obviously (P < 0.05), while MDA content increased obviously (P < 0.05). SOD activity in the three therapeutic groups increased obviously, while MDA content decreased obviously (P < 0.05); there was no significant difference among the three treatment groups (P > 0.05). CONCLUSION: ① USW and RSM therapy have neuroprotective effects against focal cerebral ischemia-reperfusion injuries by means of decreasing cerebral water content and MDA and increasing the activity of SOD. ② Synergistic action was not observed between these two therapeutic methods. BACKGROUND: How to control the effect of oxygen-derived free radicals on development of cerebral injury and cerebral edema is a key factor for treating cerebral ischemia-reperfusion injury. OBJECTIVE: To observe and compare the protective effects, synergistic action and mechanisms of ultrashortwave ( US) and radix salviae miltiorrhizae (RSM) on the focal cerebral ischemia-reperfusion injuries in rats. DESIGN: Randomized controlled animal study. SETTING: Department of Rehabilitation Medicine, First Hospital affiliated to China Medical University. MATERIALS: A total of 160 healthy Wistar rats of both genders and aged 18-20 weeks weighing 250-300 g of clean grade were selected in this study. 5 mL / ampoule RSM injection fluid was produced by the First Pharmaceutical Corporation of Shanghai (batch number: 011019, 0.01 mL / g The USW therapeutic device was produced by Shanghai Electronic Device Factory with the frequency of 40.68 MHz and the maximal export power of 40 W. The first channel of power after modulation was 11 W. METHODS: The experiment was carried out in the Rehabilitation Medicine Department of the First Hospital affiliated to China Medical University from May 2002 to January 2003. Focal ischemia-reperfusion model was established in rats by reversible right middle cerebral artery The scores of neurological deficits were evaluated by 0 to 4 scales. After surgery, 64 successful rats models were divided into four groups according to digital table: control group , USW group, RSM group and RSM + USW group with 16 cases in each group. Rats in control group were intraperitoneally injected with the same volume of saline (0.1 mL / g); rats in USW group were given small dosage of USW on head for 10 minutes at 6 hours after reperfusion; rats in RSM group were injected intraperitoneally with 0.01 mL / g RSM solution at 30 minutes before reperfusion; rats in RSM + USW group wereAll 80 rats were reperfusion and given a small dosage of USW on head for 10 minutes once at 6 hours after reperfusion; sixteen rats in sham operation group did not receive any treatment. brains at 24 hours after reperfusion to measure wet and dry weights to calculate water content: Cerebral water content (%) = (1-dry / wet weight) × 100%. Superoxide dismutase (SOD) activity was measured by hydroxylamine method and malondialdehyde MDA: content was measured by TBA photometric method. MAIN OUTCOME MEASURES: Cerebral water content, SOD activity and MDA content. RESULTS: All 160 rats except 80 failing in modeling were involved in the final analysis. ① The cerebral water content of left hemisphere made no significant difference (P> 0.05). The cerebral water content of the right hemisphere in the control group and the three treatment groups was obviously higher than that of the sham operation group [(81. 26.7% ± 0.77%, 79.74 ± 0.68%, 79.76 ± 0.81%, 79.61 ± 0.79%, 77.43 ± 0.61%, respectively, P <0.05] groups was obviously lower than that of the control group (P <0.05). There was no significant difference among the three treatment groups (P> 0.05). ② Compared with the control group, SOD activity (P <0.05) while MDA content increased obviously (P <0.05). SOD activity in the three therapeutic groups increased obviously, while MDA content decreased obviously (P <0.05); there was no significant difference among the three treatment groups (P > 0.05). CONCLUSION: ① USW and RSM therapy have neuroprotective effects against focal cerebral ischemia-reperfusion injuries by means of decreasing cerebral water content and MDA and increasing the activity of SOD. ② Synergistic action was not observed between these two therapeutic methods.