Effect of electroacupuncture at acupoint Guanyuan on excitability of detrusor and expression of BDNF and TrkB in spinal cord of rat with urinary retention after spinal cord injury

Abstract

Objective To study the effect and mechanism of electroaeupuncture at acupoint Guanyuan on expression of brain-derived neurotrophic factor (BDNF) and tropomyosine receptor kinase B (TrkB) in spinal cord and excitability of detrusor of rat with urinary retention after spinal cord injury. Methods The model of urinary retention after spinal cord injury was established by using weight drop method. Eighty female Sprague-Dawley rats were randomly divided into four groups, namely, a normal, a sham, a model and an electroacupuncture (EA) group, with 20 rats in each group. The EA group was given electroacupuncture at aeupoint Guanyuau once a day for 10 days in total, while the other groups was given no treatment. After 10 days, the expression level of BDNF and TrkB in spinal cord of injury site was measured by immunohistochemistry staining, and excitability of detrusor was measured by using the muscle strips in vitro. Results It was revealed that, with regard to the expression level of BDNF and TrkB in spinal cord,the model group exceeded the normal and sham group, the EA group significantly exceeded the other groups ( P < 0. 05 ). With regard to the excitability of detrusor, the model group was significant-ly lower than the normal and sham group. The EA group significantly exceeded the model group ( P < 0.05 ). Conclusion Electroacupuncture at acupoint Guanyuan can raise the expression level of BDNF and TrkB in spinal cord and increase the excitability of detrusor in rats with urinary retention after spinal cord injury. Key words: Urinary retention; Electroacupoint; Acupoint Guanyuan; BDNF; TrkB