[Effects of electroacupuncture on the expression of epidermal growth factor receptor and glial fibrillary acidic protein after spinal cord injury in rats]

Abstract

Objective: To study the molecular mechanism of electroacupuncture (EA) in the treatment of spinal cord injury (SCI) in rats.

Methods: Forty-five male SD rats were randomized into control, model and EA groups with 15 cases in each group which was further divided into 3 subgroups (3 d, 7 d and 14 d) at average. SCI (T10) model was duplicated by using modified Allen's method. EA (2 Hz, 2-6 mA) was applied to bilateral "Jiaji" [EX-B 2, superior and inferior to the injured locus (T10)] for 30 min, continuously for 3 days, 7 days and 14 days respectively in different subgroups. Changes of SCI rats' behavior (hind-limb motor) were detected by using Basso Beattie Bresnahan (BBB) locomotor scoring scale. The immuno-reaction (IR) activity of epidermal growth factor receptor (EGFR) and glial fibrillary acidic protein (GFAP) in gray matter of the injured cord was determined using immunohistochemical technique on day 3, 7 and 14 separately.

Results: Compared with control group, BBB scores of model and EA groups were significantly lower in the 3 subgroups (P < 0.01); while in comparison with the 3 subgroups of model group, BBB scores of the corresponding time in EA group were significantly higher (P < 0.01). Compared with control group, IR-positive cells of both EGFR and GFAP in model and EA groups increased remarkably at the 3 time-points in number (P < 0.01); while those of EGFR and GFAP of EA group were significantly fewer than those of model group at the 3 time-points (P < 0.01).

Conclusion: EA can effectively improve SCI rats' hind-limb locomotor, which may be closely related to its functions in suppressing the expression of EGFR and GFAP in the injured spinal cord and in promoting nerve axon regeneration.