慢性脊髓损伤组织学变化及神经细胞的实验研究凋亡

目的 :建立慢性压迫性脊髓损伤的动物模型 ,观察组织病理学变化及细胞的凋亡。方法 :自制压迫装置 ,造成兔 L2脊髓的慢性压迫。尼氏染色观察一般组织病理变化 ,原位末端标记方法 (TU NEL)标记凋亡的细胞。结果 :实验组压迫区白质神经胶质细胞增生 ;后索较重 ,侧索及前索较轻 ;神经元尼氏小体淡染、消失 ;神经元萎缩 ,脱失 , 板层明显。标记阳性细胞为神经胶质细胞 ,各索内均可见到 ,后索及侧索明显。灰质中阳性细胞数量较少 ,为神经胶质细胞 ,主要在 、 板层。相邻段病变次之 ,远段接近正常。对照组与实验组相比细胞凋亡数大为减少 (P<0 .0 5 ) ,与正常组比较区别不大 (P>0 .0 5 )。在各组每段都未观察到阳性标记神经元。结论 :机械性压迫是病理变化的主要因素 ,也是细胞凋亡的主要原因 ;神经胶质细胞的凋亡可能是继发病变的机制之一。

Expriment Study on Histopathologic Changes and Neurocyte Apoptosis with Chronic Spinal Cord Injury

Objective To observe the general histopathological changes and cells apoptosis of compressive spinal cord injuries, which get from self-made animal models. Methods 16 healthy rabbits were radomly and bindly divided into three groups, The experimental group (n=8) was compressed grandually, the control group (n=5) was compressed without pushing the piston, the normal group (n=3) recieved the same operation. The general histopathologic changes were observed with Nissl stain, and apoptosis cells were marked with TUNEL. Results In experimental group, the narrow ratios of tuber vertbrae were 30.4 % to 45.5 %, galial cells in the grey matter were found, Nissl bodies of neuron were lightly stained and disappeared, and neurons were atrophy and declined in grey matter, with Nissl stain. Marked Positive cells were galial cells, every funiculus would find them, the quantity of positive cells was less in the grey matte. The changes in the adjoining block were slight, and the changes of distal block were near to normal.Apoptosis cells were less in the contral group than that in the experimental group (P<0.05), and there were no much difference (P>0.05) compared with the normal group. positive marked neurons were not observed in every block of all groups.Conclusion This model proved to be a true chronic spinal cord compression model according to obeservation, mechanisical compression was the main reason for the pathologic changes of the compressed spinal cord, the galial cells apoptosis may be a mechanism to the sencondary lesion of spinal cord injuries.