Oscillating field stimulation inhibits astroglial scar formation in spinal cord injured rats

Objectives: Weinvestigated how oscillating field stimulation (OFS) would affect astroglial scar formation and astrocyte activation following spinal cord injury (SCI) in rats. Methods: SD rats were divided into three groups: (1) sham group (n=20), received laminectomy only; (2) control group (n=20), received sham (inoperative) oscillating field stimulator units after SCI; and (3) OFS group (n=20), received active stimulator units after SCI. The electric field intensity was 600muV/mm, and the polarity alternated every 15 min. Eight weeks after the surgery, the cavity formation, the expression of the astrocytes marker (GFAP), the products secreted by astrocytes (Neurocan) and the proliferating cells marker (PCNA) were detected 8 weeks post the injury.Results: Compared to the control group, Luxol fast blue (LFB) staining indicated that OFS reduced cavity formation (P<0.05), immunofluorescent labeling showed that OFS markedly reduced the positive area of GFAP (P<0.05). Moreover, the western blot assay indicated that, OFS decreased the expression of GFAP, neurocan and PCNA (P<0.05). Conclusions: These findings suggested OFS could reduce astroglial scar formation after spinal cord injury in rats, and the effects may be related to the inhibiting of astrocyte activation.