Morphological changes of motor neurons of spinal cord after peripheral nerve injury

Objective To investigate the morphological changes of apoptosis in motor neurons of spinal cord following transection of the peripheral nerve in adult rats. Mehtods Twenty-five adult Sprague-Dawley rats were randomly divided into operation group and normal group. The sciatic nerve injuried model was set up and double ligation of the proximal stump. The rats were sacrificed on the 3rd, 7th, 14th and 21st postoperative day respectively. The spinal cord of L4 to L6 was harvested, and the cells of motor neuron of spinal cord were observed under light microscope and electronmicroscope.Meanwhile,the TUNEL technique was applied for detection of apoptotic motor neurons. Results The typical apoptotic cells could be observed during 3rd to 21st day after operation. The number of apoptotic cells reached a peak a week later. What’s more, apoptotic cells staying in different stages and typical apoptotic body could be found at the same time. Conclusion Apoptosis of motor neurons of spinal cord is an important morphological change after transection of the peripheral nerve.