Impact of electro-acupuncture on EAAT2 and NMDAR-2B expression in goats with visceral hypersensitivity.

OBJECTIVE

This study evaluates the effect of electro-acupuncture (EA) on visceral hypersensitivity (VH) and the expression of N-methyl-D-aspartate receptor-2B (NMDAR-2B) and glutamate transporter EAAT2 in goats.

METHODS

Twenty-four goats were divided into four groups: saline, 2, 4, 6-Trinitrobenzenesulfonic acid (TNBS), TNBS + EA, and sham EA. EA was administered at Zusanli (ST36) with 60 Hz and 1-3 mA on specified days. Electromyography (EMG) recorded visceromotor response to colorectal distention (CRD). Spinal cords were collected for immunohistochemistry, western blotting, and RT-PCR. The ileum was examined histologically.

RESULTS

The repeated EA administration significantly attenuated VH (P < 0.05) in TNBS-treated goats without similar effects in the sham group. NMDAR-2B expression increased (P < 0.01), and EAAT2 expression decreased (P < 0.01) in the TNBS group compared to saline. EA increased the EAAT2 and decreased the NMDAR-2B expression (P < 0.01) compared to TNBS, with no change in the sham-EA group.

CONCLUSION

EA may alleviate VH by upregulating EAAT2 and downregulating NMDAR-2B in the spinal cord of TNBS-treated goats, indicating its potential for treating chronic visceral pain in gastrointestinal disorders.