坐骨神经损伤后大鼠脊髓腰段前角AChE的变化

The Dynamic Change of Acetylcholinesterase(AChE)in the Ventral Horn of the Rat Lumbar Spinal Cord after Sciatic Lesion

结扎切断 SD 大鼠左侧坐骨神经或前后根后,在一定的存活时间序列里,用 Olympus显徽镜的测光装置对经 EL—Badawi 氏改良法显色处理后的脊髓腰段前角乙酰胆硷酯酶(ACHE)进行了相对变化率(Xo/Xc—1)×100%的测定。结果发现坐骨神经切断术后,术侧脊髓前角 AChE10天后增高22.1%;术后25天时减少到-20.2%;60天时又再次增高22.8%,呈双峰夹低谷的变化曲线。切断前后根后,术侧脊髓前角 AChE10天后明显下降(-21.1%);提示外周神经受损部位不同,脊髓前角 AChE 发生变化的情况不同.根据分析,本文将双峰夹低谷曲线分为1.应激期;2.调整期;3.恢复期.外周神经受损后有关神经元将出现变性和再生现象.神经变性和再生过程中形态学方面的研究至今已有百余年的历史;神经递质及其代谢酶在神经系统中正常分布的研究也有了几十的年历史;但在神经变性和再生的过程中,神经递质及其代谢酶的动态变化的研究正在兴起。神经元受损后神经递质及其代谢酶的动态性变化,在一定程度上反映了神经细胞对伤害性刺激的反应。1987年 Malatova 在狗发现 AChE 在远侧残根中是先显著下降,后轻微下降;在近侧残根中和在前角中是先升后降.但在更长时间里的变化情况怎样?以及在大鼠脊髓前角中的变化情况又如何?这种变化与外周神经损伤部位的关系又怎样?目前尚无报导。为了探讨这些问题,本文应用组化方法进行染色,利用照相显微镜的曝光时间对AChE 的染色强度作了相对量的测定。

The Ligation and transection of sciatic nerve or spinal rhizotomy were taken on the Sprague--Dawly rat.The sections of lumbar spinal cord were stained for Aeetyl- eholinesterase(AChE)using EL-Badawi's Improved Method at intervals after opera- tion.The staining intensity of AChE in the ventral horn were measured by the exposure measuring device of Olympus microscope.The dynamic change of AchE was described by the relative changing rate((?)c/(?)o-1)x100%. We found that AChE of operative side increased to 22.1% on the 10th day after tran- section,and it fell below contral value levels to the-20.2% on the 25th day,but by the 60th day,it increased to 22.8% again.The changes of AChE show a curve which pos- sesses a valley between two peaks.On the other hand,a marked(-21.1%)decrease in AChE was found on the 10th day after rhizotomy.These suggest that the changes of AChE varied with positions of peripheral lesion.We divided the curve into 1)Stress peri- od;2)Adjustment period 3)Recovery period.