Objective: To investigate the effects of electro-acupuncture at Shuigou (DU26) on latency and amplitude of motor evoked potential (MEP) in rats after cerebral infarction.
Methods: Fifty healthy male Wistar rats were randomly divided into five groups as normal group, untreated group, sham-operated group, non-acupoint group and Shuigou group, with 10 rats in each group. By using a modification of the technique of middle cerebral artery occlusion, focal cerebral ischemia injury was induced in rats except normal and sham-operated groups. Rats in the normal group received no treatment. Rats in the sham-operated group underwent identical experimental procedures as the other groups, except that the nylon suture was inserted into the internal carotid artery. After the behavioral deficit was evaluated by using Zausinger 6-point neurological function score, rats in the Shuigou group and non-acupoint group were separately acupunctured and stimulated by continuous-wave with 2 Hz frequency, 1 mA intensity, for 10 minutes, twice a day for 3 days. Non-acupoint was located at the left side 0.5 cm of the Shuigou point. No intervention was given to the other groups. Zausinger 6-point neurological function and MEP were measured after 72-hour treatment.
Results: The latency at the affected side in the untreated group was significantly longer than that in the normal group (P<0.05), and the amplitude at the affected side was significantly reduced (P<0.01). After 3-day electro-acupuncture, the latency at the affected side of rats in the Shuigou group was obviously shortened as compared with the untreated group (P<0.05), and the amplitude was significantly increased (P<0.05). The latency at the affected side in the Shuigou group was shorter than that in the non-acupoint group (P<0.05), and the amplitude tended to increase as compared with the non-acupoint group, but there were no significant differences (P>0.05). There were no significant differences on the latency and amplitude between the untreated group and non-acupoint group (P>0.05). The neurobehavioral score of the Shuigou group was significantly higher than those of the untreated group and non-acupoint group (P<0.05), and there were no significant differences between the untreated group and non-acupoint group (P>0.05).
Conclusion: Electro-acupuncture at Shuigou can increase the latency and amplitude of MEP in rats after cerebral infarction.