Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: Expression of semaphorin 3A and its receptors in the human intervertebral disc: potential role in regulating neural ingrowth in the degenerate intervertebral disc. | Tolofari et al. Arthritis Research Therapy 2010 12 R1 http content 12 1 R1 RESEARCH ARTICLE Open Access Expression of semaphorin 3A and its receptors in the human intervertebral disc potential role in regulating neural ingrowth in the degenerate intervertebral disc Sotonye KTolofari Stephen M Richardson Anthony J Freemont and Judith A Hoyland Abstract Introduction Intervertebral disc IVD degeneration is considered a major underlying factor in the pathogenesis of chronic low back pain. Although the healthy IVD is both avascular and aneural during degeneration there is ingrowth of nociceptive nerve fibres and blood vessels into proximal regions of the IVD which may contribute to the pain. The mechanisms underlying neural ingrowth are however not fully understood. Semaphorin 3A sema3A is an axonal guidance molecule with the ability to repel nerves seeking their synaptic target. This study aimed to identify whether members of the Class 3 semaphorins were expressed by chondrocyte-like cells of the IVD addressing the hypothesis that they may play a role in repelling axons surrounding the healthy disc thus maintaining its aneural condition. Methods Human IVD samples were investigated using reverse transcription polymerase chain reaction RT-PCR to identify gene expression of sema3A 3F and their receptors neuropilins 1 and 2 and plexins A1-4 . Sema3A protein was also localised within sections of normal and degenerate human IVD and immunopositivity quantified. Serial sections were stained using and CD31 to correlate semaphorin 3A expression with nerve and blood vessel ingrowth respectively. Results Sema3A protein was expressed highly in the healthy disc primarily localised to the outer annulus fibrosus. In degenerate samples sema3A expression decreased significantly in this region although cell clusters within the degenerate nucleus pulposus exhibited strong immunopositivity. mRNA for sema3A receptors was also identified in healthy and .
