Effect of Hyperbaric Oxygenation on Intervertebral Disc Degeneration An In Vivo Study With Sprague-Dawley Rats

Study Design. An in vivo study was conducted to test the effect of hyperbaric oxygenation (HBO) on intervertebral disc degeneration in Sprague-Dawley rats. Objective. To observe the changes in intervertebral disc height and levels of glycosaminoglycan, collagen, interleukin-1 beta (IL-1 beta), prostaglandin E-2 (PGE(2)), and inducible nitric oxide synthase (iNOS) in degenerated intervertebral discs after HBO therapy. Summary of Background Data. Although the involvement of IL-1 beta, PGE-2, NO, and low O-2 concentration has been demonstrated in intervertebral disc degeneration, the actual mechanism is not clear. It has been reported that HBO influences changes in IL-1 beta, PGE-2, NO, and O-2 concentration. Previously, a study demonstrated an in vitro positive effect of HBO on the human nucleus pulposus. Thus, an in vivo study in animals was necessary. Methods. Twelve Sprague-Dawley rats were each injected with chondroitinase ABC in 2 proximal intervertebral discs of the tail. After treating with 100% oxygen at 2.5 atmospheres 2 hours per days for 10 days, the change in disc height was determined by radiography. The amounts of PGE-2, iNOS, glycosaminoglycan, and total collagen in the intervertebral disc were quantified by enzyme-linked immunosorbent assay. Tissue morphology and the distribution of glycosaminoglycan, IL-1 beta, and iNOS in the intervertebral disc were assessed by histology and immunohistochemistry. The area of IL-1 beta in the intervertebral discs was quantified using image analysis software. Results. HBO therapy stopped the decrease in intervertebral disc height, caused an increase in the amount of glycosaminoglycan, and inhibited IL-1 beta, PGE-2, and iNOS production. Conclusion. HBO provides a potential treatment modality for intervertebral disc degeneration.