The Effect On The Activity Of Phospholipase A2 Of BMP Injected Into The Lumbar Nucleus Pulposus Of Rabbits

Objective: To study the concomitant effect of BMP on the activity of thephospholipase A2 (PLA2), which were injected into the lumbar nucleus pulposus of the rabbits in order to enhance the intervertebral fusion.Method: 36 white rabbits of New Zealand were obtained which weighed within therange of 3-4kg. These rabbits were divided into 2 groups randomly, with 18 rabbits in each group. Every rabbit was incised at the side of its waist, including the experiment group of 18 rabbits, of which 200mg BMP was injected into the nucleus pulposus of the L4-5 intervertebral discs, and the control group of 18 rabbits, of which the same dosage of 0.9% NS was injected into the nucleus pulposus of the L4-5 intervertebral discs respectively. After 1 month postoperatively, 9 rabbits chosen randomly from the eperiment group and another 9 rabbits chosen from the control group were killed and the organizations of the intervertebral discs of L4-5 were harvested and stored under 0℃. In the same way the organizations of the intervertebral discs of L4-5 of the other 18 rabbits lefe, 9 in each group, were acquired. The activities of PLA2 were tested through the method of trace acid titration and the values obtained were analyzed statistically.Result: The activities of PLA2 of the experiment group, in which BMP wereinjected into the intervertebral discs of L4-5, were evidently lower than those of the control group, in which 0.9%NS were used. In detail, the activities of PLA2 of L4-5 intervertebral discs began to go down after 1 month postoperatively, but the difference between them had no significance statistically. 3 months after operation, the activities of PLA2 of L4-5 intervertebral discs in the experiment group were much more reduced than those of the control group with significant difference in statistics. Furthermore, the trend of reduction of the activities of PLA2 were greatly obvious with the lapse of the time, compared the effect of BMP of 1 month after operation with that of 3 months longitudinally and the difference between their average values garnered showed a statistical significanceConclusion: The injection of BMP into the lumbar intervertebral discs could notonly enhance the anterior intervertebral fusion in an effort to remedy the unstability caused by the diseases of the intervertebral discs, but also lower the activity of PLA2 at the same time in an attempt to eliminate the effect of the inflammatory factors, which might play an important role in the intervertebral disc degeneration and protrusion.