银杏叶提取物影响臂丛撕脱后运动神经元NOS表达及其存活

目的:观察EGb761对脊神经根撕脱后前角运动神经元的保护作用和对NOS表达的影响。方法:成年Sprague-Dawley雌性大鼠80只, 行脊髓C5-T1神经根撕脱术后, 治疗组每天腹腔注射1mLEGb761, 25mg·kg^-1·d^-1;对照组注射等量生理盐水。治疗后1周、2周、4周和6周分别处死动物, 取脊髓C7节段行NADPH-d组化和中性红染色, 计数各组动物损伤侧前角NOS阳性和中性红阳性的运动神经元数目, 比较组间差异显著性。结果:脊神经根撕脱后受损运动神经元NOS表达从1周开始, 2周达高峰, 4周-6周逐渐下降。运动神经元死亡以4周-6周最明显。EGb761能减少以上各时点NOS阳性运动神经元的数目, 提高各时点运动神经元的存活。结论:EGb761能下调运动神经元NOS基因表达, 提高受损运动神经元的存活。

Influence of Ginkgo biloba extract on NOS expression and survival of C7 motoneurons following brachial root avulsion

AIM:To investigate the influence of EGb761 on NOS expression and survival of motoneurons after spinal root avulsion.METHODS:Eighty adult SD female rats were randomly divided into control and EGb761 groups. The C5-T1 nerve roots of right brachial plexus were avulsed and injection of 1 mL of either EGb761 25 mg·kg^-1·d^-1 or normal saline (ip) was performed everyday. The treated rats were killed 1 week, 2 weeks, 4 weeks and 6 weeks following avulsion. The cryostat sections of C7 segment of every rat were collected and carried with NADPH-d histochemistry plus neutral red counterstain. The difference of the numbers of both NOS-positive and survival motoneurons were quantitatively studied.RESULTS:Following avulsion, NOS was expressed in avulsed motoneurons at 1 week, reached to its maximum at 2 weeks and then decreased gradually from 4 weeks to 6 weeks. Motoneurons died from 4 weeks to 6 weeks. With EGb761 treatment, the number of NOS-positive motoneurons were decreased at each time point and the number of survival motoneurons was increased at each time point compared to control rats.CONCLUSIONS:EGb761 protected the spinal cord motoneurons from avulsion injury. This effect may be related to inhibition of NOS expression.