SD大鼠脊髓全横断损伤后神经细胞凋亡的研究

目的检测SD大鼠脊髓全横断损伤后神经细胞凋亡的形态及数量变化.方法建立SD大鼠脊髓全横断损伤模型,采用原位细胞凋亡TUNEL法检测术后3、7、14d和21d损伤断面头、尾侧脊髓中凋亡神经细胞的形态及数量变化.结果损伤后不同时点脊髓灰、白质均有凋亡细胞分布,细胞核呈紫色及黄褐色双重染色,形态不一;损伤后3d,脊髓损伤断面头、尾端腹角即出现大量神经细胞凋亡,并持续至21d;各时点头、尾侧与假手术组比较,脊髓腹角神经细胞凋亡数均增加（P〈0.05）;凋亡的胶质细胞数在21d较14d减少（P〈0.05）.结论脊髓损伤后广泛存在神经细胞凋亡,是继发性损伤的主要形式.

The Study on the Neurocytic Apoptosis in Rats Following Complete Spinal Cord Transection

Objective To detect the morphological and quantative changes of apoptotic neurocytes in adult rats subjected to transected spinal cord injury.Methods The model of rats suffered complete cord transection was used. Terminal deoxynuleotidyl-mediated nick end labeling （TUNEL） was used to detect the expression of neuyocytic apoptosis in both caudal and rostral cord stump to the injured site after operation （3,7、14、21 days）.Results TUNEL-positive cells stained by yellow and blue were seen in the whole spinal cord,positive products located in the nucleus.A great number of TUNEL-positive cells were observed in caudal and rostral cord stump to the injured site at 3 days postoperation,and lasting to 21 days postoperation,presenting a significant increase compared with sham-operated control group （P 〈 0.05）. Conclusion Apoptosis of neural cells occurr extensively,it may be a main dead pattern in the secondary lesioned period after spinal cord injury.