Journal
SPINE
Volume 34, Issue 21, Pages 2263-2269Publisher
LIPPINCOTT WILLIAMS & WILKINS
DOI: 10.1097/BRS.0b013e3181a5521d
Keywords
NGF; substance P; dorsal root ganglion; intervertebral disc; low back pain
Categories
Ask authors/readers for more resources
Study Design. We investigated the mechanism of discogenic low back pain using an in vitro model. Objective. To evaluate the axonal growth and induction of a painful neuropeptide, substance P (SP), using rat dorsal root ganglion (DRG) neurons and degenerated human disc cells in vitro. Summary of Background Data. Degeneration of the lumbar intervertebral disc is a cause of low back pain. The pathologic mechanism is thought to be sensory nerve ingrowth into the inner layers of the degenerated intervertebral disc; however, the precise patho-mechanism has not been clarified. Methods. The nucleus pulposus (NP)and annulus fibrosus (AF) of human intervertebral discs were harvested from patients with discogenic low back pain. Extracted medium from human degenerative intervertebral discs was cultured with neurons of rat DRGs. We evaluated the promotion of axonal growth and SP induction of DRG neurons in extracted medium from the NP and AF using immunocytochemistry. Results. The average length of growing axons in the NP and AF was significantly longer than that in the control (P < 0.005). That in the NP was significantly longer than that in the AF. The average length of growing axons in the NP was significantly shortened after anti-nerve growth factor (NGF)beta treatment (P < 0.005); however, that in the AF was not (P < 0.05). The percentage of SP-immunoreactive cells with growing axons was significantly higher only in the NP group compared with the control and AF groups (P < 0.005), and anti-NGF beta treatment decreased the expression of SP in the NP group (P < 0.05). Conclusion. Extracted medium from the NP and AF promoted axonal growth. Furthermore, NGF from the NP promoted axonal growth and induced SP. These in vitro results may suggest that NGF from the NP promotes the growth of sensory nerve fibers innervating the degenerated intervertebral disc and may induce SP related with pain transmission.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available