Abstract: Objective To investigate the protective effect and cytosolic phospholipase A2 (cPLA2) associated mechanism of panax notoginseng saponins (PNS) in spinal cord hemisection injured rats. Methods 55 adult Sprague-Dawley rats were randomly divided into three groups: sham group (n=5), spinal cord injury group (n=25) and PNS group (n=25). The rats were evaluated with BBB score, pathology and immunohistochemistry 1 d, 3 d, 7 d, 14 d and 21 d after intervention. Results Compared to the spinal cord injury group, motor recovery was significantly better in PNS group 3 d, 7 d, 14 d and 21 d after intervention (P<0.05). Nissl staining showed less neuron necrosis and more integrated neural cells in morphology in PNS group 7 d, 14 d and 21 d after intervention. Cytosolic phospholipase A2 (cPLA2) expression was inhabited, and less number of positive cells were found in PNS group 7 d, 14 d and 21 d after intervention. Conclusion PNS can inhibit the expression of cPLA2 after spinal cord injury, which may be one of the mechanisms of its effect on promoting motor recovery.

Key words: panax notoginseng saponins, spinal cord injury, cytosolic phospholipase A2, rats