The Expression And Correlation Analysis Of CTGF And CD34in Degenerated Intervertebral Disc Of Rat Tails

Objectives To observe the expression of connective tissue growthfactor (CTGF) and CD34in degenerated intervertebral disc of rat tails,discuss the correlations between CTGF expression, angiogenesis anddegeneration of intervertebral disc, identify the role of CTGF in discdegeneration.Methods A total of24SD rats were divided randomly into2groups afterthe procedures that coccygeal (Co)7/8and8/9intervertebral discs hadbeen selected for injury of percutaneous puncture in the unilateralannulus fibrosus by a22-gauge needle, the control group were given agavage of2ml normal saline (NS) every day, and0.05%atorvastatinsuspension had been used in the experimental group. The discs includingpunctured (Co7/8,8/9) and unpunctured one (Co6/7,9/10) were harvested4,6and8weeks later, then observed the histologic changes andangiogenesis of intervertebral disc by hemotoxylin-eosin staining andmeasured the expression of CD34and CTGF in disc by immunohistochemicaltechniques.Results There were varying degrees of angiogenesis in the discs whichhad been punctured and especially in the experimental group at8weeks.The results of disc histologic grading score displayed that discdegeneration aggravated gradually with time in the injury processedlevels. Punctured disc in the experimental groups degenerated moreserious than unpunctured one at every test time (P<0.05). The internaldisc expression of CD34and CTGF resulted higher positive in the punctured groups significantly (P<0.05), and the experimental groups were higherthen control groups every time among them (P<0.05). But in the unpunctureddiscs, experimental groups presented higher level expression of CD34at8weeks (P<0.05) and CTGF at4weeks (P<0.05). Disc histologic gradingscore showed positive correlation with the expression of CD34(r=0.729,P<0.01) and CTGF (r=0.780, P<0.01), and there were significant positivecorrelation between them (r=0.828, P<0.01).Conlusions CTGF and CD34presented high expression in degeneratedintervertebral disc of rat tails, there were positive correlation amongdisc angiogenesis, degeneration and CTGF expression. Excessiveexpressing of CTGF when the intervertebral discs angiogenesis may promotethe degeneration in itselves.