The Study Of AQP1and AQP3Expression In The Human Different Level Of Degeneration Intervertebral Disc Nucleus Pulposus Cells

Objective: Intervertebral disc degeneration is an important cause of low back pain, but so far, the physiological and pathological mechanism of IVDD remains unclear. Degeneration of the nucleus pulposus is the central link in the IVDD, this study is to be adopted by immunohistochemical methods and Real time-PCR technology to compared the expression level of Aquaporinl and Aquaporin3of the nucleus pulposus in the normal group and the degenerative group, and explore the role of AQP1and AQP3in the nucleus pulposus, to understand the Aquaporins in the physiological and pathological significance of the nucleus pulposus, to seek a new kind of the pathophysiological mechanisms of IVDD, and then to supply new idea and direction for the prevention and treatment of IVDD.Methods:The nucleus pulposus specimens were divided into5grades according to the Pfirrmann classification method, and the1-5grade corresponding to the A-E group. The specimens were fixed, washed, dehydrated, transparent, dip wax, embedded, and sectioned. And then use HE staining to observe the pathological manifestations of the degenerate nucleus pulposus tissue. Subsequently observing the expression levels of AQP1and AQP3by use of immunohistochemistry and Real time-PCR technique, and to measure its expression level of the mean optical density of immunohistochemical positive cells and mRNA.The data were analyzed by the one-way ANOVA analysis of SPSS17.0. Results:1. HE staining:The normal group:the structure of the nucleus pulposus were loose, the matrix components were complete, the nucleus pulposus cells were plenty, collagen fibers run clear, and the nuclear structure was integrity. The degeneration group: the nucleus pulposus tissue were shrinkage, the matrix components were less, the collagen fibers hyperplasy crassitude and run disorder, the nucleus pulposus cells were less, and the nucleus structure was incomplete.2. Immunohistochemical analysis:The positive cells expressed of AQP1and AQP3are significantly reduced in the degeneration group compared with the normal group, and the MOD values are decreased progressively with IVDD severity. The one-way ANOVA analysis to MOD values among the groups, AQP1:compared to the group A between the group C, D and E, the group B between the group D and E, the group C and group E, the group D and the group E, the difference were statistically significant (P<0.05); there were no difference statistical significance among the other groups (P>0.05). The MOD values of AQP3in each group pairwise differences were statistical significance(P<0.05). The Pearson product-moment linear correlation analysis to the MOD values of AQP1and AQP3between the Pfirrmann grades and the age:there was a significant inversely correlated to the AQP1and the Pfirrmann grades(r=-0.862,P<0.01), AQP3and Pfirrmann grades was a significant inverse correlation(r=-0.944,P<0.01); there was a significant inversely correlated to the AQP1and the age(r=-0.794,P<0.01), AQP3and Pfirrmann grades was a significant inverse correlation(r=-0.881,P<0.01).3. Real time-PCR analysis:The Col II mRNA expression of nucleus pulposus was reduced significantly in the degeneration group compared with the normal group, and the mRNA expression of AQP1and AQP3were decreased progressively with IVDD severity. The one-way ANOVA analysis to the mRNA expression of AQP1and AQP3, AQP1:compared to the group A between the group C, D and E, the group B between the group D and E, the group C and the group E, the differences were statistically significance(P<0.05); there was no difference statistically significance among the other groups(P>0.05). AQP3:compared to the group A between the group C, D and E, the group B between the group D and E, the group C and the group E, the differences were statistically significance(P<0.05); there was no the difference statistically significance among the other groups(P>0.05).Conclusion:It was significant difference that the gene and protein expression of the AQP1/AQP3in the normal human nucleus pulposus and the degenerative nucleus pulposus; Compared with the normal nucleus pulposus, the expression of the AQP1/AQP3was significantly reduced in the degenerative nucleus pulposus; and the expression of AQP1/AQP3in the content was reduced progressively with the increasing level of the nucleus pulposus degeneration.