中文摘要：

目的探讨注射甲基强的松龙（MP）对大鼠脊髓半横断后运动终板乙酰胆碱酯酶（AChE）表达的影响。方法 Wistar雄性大鼠96只,包括假手术组（A组,n=16）、脊髓半横断组（B组,n=40）和脊髓半横断后MP治疗组（C组,n=40）,B、C组分别作右侧脊髓半横断术,C组术后MP干预;术后1 d、3 d、1周、2周、4周分别取右下肢腓肠肌制作冰冻切片,铜-铁氰化物改良染色法检测AChE的表达,比较各组标本阳性表达区的平均光密度值。结果 3组大鼠腓肠肌冰冻切片中均有表达AChE的棕色染色区;脊髓半横断术后1 d,3组大鼠腓肠肌切片中AChE染色区的平均光密度值无统计学差异（P〉0.05）;术后3 d,B、C组AChE染色区平均光密度值均低于A组,差异有统计学意义（P〈0.05）,但B、C组之间无统计学差异（P〉0.05）;术后1周、2周,B组AChE染色区平均光密度值低于C组,B、C组均低于A组,差异均有统计学意义（P〈0.05）;术后4周,C组AChE染色区平均光密度值明显恢复,与A组比较无统计学差异（P〉0.05）,B组仍维持低水平,平均光密度值低于A、C组（P〈0.05）。结论脊髓半横断后运动终板AChE水平下降,MP早期干预有助于骨骼肌运动终板AChE表达水平的恢复。

英文摘要：

Objective To study the effects of methylprednisolone（MP） on acetylcholinesterase（AChE） in gastrocnemius neuromuscular junction after spinal cord injury in rats.Methods Ninety-six 10-week-old SPF Wistar male rats were randomly divided into 3 groups,including sham operation group（A group,n =16）,spinal cord injury group（B group,n =40） and MP treated group（C group,n =40） after spinal cord injury.B,C group received the right spinal cord semi-transection,and MP intervention was given to C group after surgery;right leg gastrocnemius were collected on d1,d3,w1,w2 and w4 for frozen sections.The expression of AChE was detected by Copper-iron cyanide improved staining.We measured the average optical density of specimens for positive expression area of each group.Results The gastrocnemius muscle AChE expression was stained as brown;1d after spinal cord semi-transection operation,,there was no significant difference on the average optical density value of rat gastrocnemius muscle AChE stained area from 3 different groups;3 d after operation,no significant difference was observed on the average optical density of AChE staining between B and C group,but lower than group A;1 week,2 week after operation,the mean optical density value of AChE staining area in group B was lower than group C,both B and C group were lower than group A;4 week after operation,AChE staining in group C was restored,with no significant difference in group A;group B remained at low levels which was lower than A,C group.Conclusion Spinal cord injury induced AChE reduction in the level of the neuromuscular junction,MP early intervention helps to skeletal neuromuscular recovery of AChE expression.