初步探究通咽喷雾剂对大鼠舌下神经损伤后AChE与运动终板的影响关系

Preliminary Exploration on the Impacts of Tongyan Spray on AChE and Motor End-Plate after Hypoglossal Nerve injury in Rats

目的初步探讨通咽喷雾剂对大鼠舌下神经损伤后乙酰胆碱酯酶(Acetylcholinesterase,AChE)与运动终板的影响关系。方法成年Wistar雄性大鼠45只随机分为3组,即空白组、模型组、药物组各15只。空白组仅暴露神经,模型组和药物组暴露舌下神经后给予钳夹损伤造模,药物组于口咽部给通咽喷雾剂1 ml,空白组和模型组给等量的生理盐水。各组分别于造模前(0 min)、干预处理后第1 min及第10 min3个时间点测试阈强度、单收缩幅度、潜伏期作为电生理观察指标。后处死大鼠取双侧舌肌组织分别制作氯化金压片观察神经纤维和冰冻切片并经乙酰胆碱酯酶染液染色后测AChE的含量。结果 (1)舌肌收缩能力:阈强度空白组与模型组比较,差异有统计学意义(P<0.05),且模型组阈强度较空白组增大;干预10 min后,单收缩幅度空白组与模型组比较,差异有统计学意义(P<0.01),且模型组单收缩幅度小于空白组;且各时间点药物组与模型组比较,差异均无统计学意义(P>0.05);各组的潜伏期差异无统计学意义(P>0.05)。(2)光学显微镜下观察运动终板与模型组比较,各组的运动终板形态和数量差异均无统计学意义(P>0.05)。(3)AChE光密度值:与模型组比较,镜下空白组AChE阳性分布区域分布多,着色深;空白组的光密度值与模型组比较,差异有统计学意义(P<0.05);药物组与模型组比较差别不大。结论 (1)通咽喷雾剂在舌下神经损伤初期可能通过增大组织阈强度,降低单收缩幅度,降低AChE含量从而影响舌肌细胞兴奋性。(2)对潜伏期及运动终板影响不大。(3)通咽喷雾剂对舌下神经损伤模型大鼠初期的舌肌收缩能力及AChE和运动终板形态影响不大,提示该药对舌下神经损伤早期运动传出途径作用不明显。通咽喷雾剂可能通过感觉传入途径或其他机制发挥作用。

Objective To preliminarily explore the impacts of tongyan spray on acetylcholinesterase（AChE）and motor end-plate after hypoglossal nerve injury in rats.Methods Forty-five Wistar adult male rats were randomized into three groups,named a blank group,a model group and a medicine group,15 rats in each one.In the blank group,the hypoglossal nerve was exposed only.In the model group and the medicine group,after exposing the hypoglossal nerve,the damage model was established with forceps.In the model group,tongyan spray,1ml was given via oropharynx.In the blank group and the model group,the physical saline of same dose was given.Separately,in each group,before modeling（0 min）,in 1 min after intervention,and in 10 min after intervention,the threshold intensity,single contraction and the incubation period were detected as the electrophysiological observational index.After rat executed,the bilateral lingualis tissue was collectedto prepare gold chloride sheet for the observation of nerve fibers and frozen section.After dyed with AChE solution,AChE content was determined.Results Lingualis contraction ability：the difference was significant statistically in threshold strength in comparison between the blank group and the model group（P〈0.05）,and the threshold strength in the model group was increased as compared with the blank group.After the intervention for 10 min,the difference was significant in the single contraction amplitude between the two groups（P〈0.01）,and the single contraction amplitude in the model group was less than that in the blank group.The difference was not significant statistically between the medicine group and the model group at each time point（P〉0.05）.The difference was not significant in incubation period among the groups（P〉0.05）.2.Under optical microscope,compared with the model group,the morphology and number of motor end-plate were not different significantly in the other groups（P〉0.05）.3.The optical density value of AChE,compared with the model group,under microscope,AChE positive distribution was dense and the coloration was deep in the blank group.The optical density was different significantly between the blank group and the model group（P〈0.05）.There was little difference between the medication group and the model group.Conclusion1.Tongyan spray affects lingualis cell excitability probably through increasing threshold strength,reducing single contraction amplitude and AChE content at the early stage of hypoglossal nerve injury.2.There is litter impact on the incubation period and motor end-plate.3.Tongyan spray induces less impacts on the lingualis contraction ability,AChE and the morphology of motor end-plate at the early stage of hypoglossal nerve in the rat,suggesting that this medicine has less effects on motion efferent pathway at the early stage of injury.Tongyan spray plays its role probably through sensory afferent pathway or other mechanism.