[Effects of vascular endothelial growth factor vector on vascular buds of vertebral cartilaginous endplate in rabbits].

Objective: To directly inject recombinant pcDNA3.1-VEGF165 plasmid into degeneration intervertebral disc and explore its effects on vascular buds of vertebral cartilage endplate and intervertebral disc in rabbits.

Methods: Rabbits were randomly assigned into the experimental and control groups (n = 10 each). For the experimental group, the animals were anesthetized and the front vertebral body exposed. With the longitudinal ossature of front vertebral body of lumbar vertebrae as a mark, a needle was inserted at the central point of the front fourth and fifth lumbar intervertebral disc and 20 µl pcDNA3.1-VEGF165 injected. For the control group, 20 µl pcDNA3.1 was injected. At Weeks 4 and 8 post-injection, the changes of vertebral cartilage endplate were monitored by radiograph, histology and scanning electron microscopy.

Results: The vertebral cartilage endplate calcification and degeneration in the experimental group were less pronounced than that in the control group at Week 8 post-operation. The average number and diameter of vascular buds obviously increased in the experimental group at Weeks 4 and 8 post-operation. The number and diameter of vascular buds in the region of inner annulus increased compared with those in the area near nucleus pulposus.

Conclusion: The pcDNA3.1-VEGF165 plasmid may promote the vascular buds of vertebral cartilage endplate by increasing their average number and diameter and arresting the intervertebral disc degeneration.