[Effect of Electroacupuncture Intervention at Different Time-points on Locomotor Function and Apoptosis in Rats with Acute Spinal Cord Injury].

OBJECTIVE

To observe the effect of electroacupuncture (EA) intervention at different treatment time-points on locomotor function and neuronal apoptosis in rats with acute spinal cord injury (ASCI), so as to explore its mechanism under-lying improvement of ASCI.

METHODS

Seventy-two female Wistar rats were randomly divided into sham operation, ASCI model and EA groups which were further divided into 4 time-points:1, 3, 7 and 14 d (=6 at each). The ASCI model was established by weight-drop striking the exposed spinal cord (T) using a NYU impactor device. EA (0.4-0.6 mA, 100 Hz) was applied to bilateral "Jiaji" (EX-B 2) for 30 min, once a day for 1, 3, 7 and 14 days, respectively in the EA group. The Basso-Beattie-Bresnahan (BBB) grading score was used to assess the animals' locomotor function, and H.E. staining was used to display the pathological changes of spinal cord injury at different time points. The TUNEL staining was used to detect the nerve cell apoptosis of spinal cord tissue.

RESULTS

After ASCI, the BBB scores were significantly decreased and the numbers of the apoptotic nerve cells considerably increased on day 1, 3, 7 and 14 in the model group compared with the sham operation group (<0.05). In addition, H.E. staining showed severe damage of the spinal cord tissue, infiltration of inflammatory cells, increase of dead nerve neurons and glia cells in the number from day 3 to 7, and additional increase of vacuoles on day 14. Following EA intervention, the decrease of BBB scores and the increase of apoptotic nerve cell numbers were markedly suppressed on day 3, 7 and 14 (<0.05). The TUNEL staining showed a decrease of the apoptotic nerve cells from day 3 on and an improvement of the injured tissue structure from day 7 to 14 in the EA group.

CONCLUSIONS

EA stimulation of EX-B 2 can significantly improve locomotor function, and lighten the spinal cord injury in ASCI rats, presenting a time-dependant tendency, which may be associated with its effect in reducing neuronal apoptosis in the spinal cord.