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

Abstract

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. 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. 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. 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.