The Role Of Aqp₁ And Aqp₃ In The Intervertebral Disc Degeneration

【Objective】Compared the expression of AQP1(Aquaporin 1, AQP1) and AQP3(Aquaporin 3, AQP3) in the intervertebral disc between the case and the control group by immunohistochemistry in order to study and explore the role of AQP1 and AQP3 in the intervertebral disc, understand the expression, physiological and pathological significance of AQP1 and AQP3 in the intervertebral disc, and supply aid for the clinical study and new thinkings and methods to prevent and cure the interverterbral disc degeneration.【Methods】The disc of the 15 cases group (regardless of gender, average age 47.47 years, disc degeneration observed in MRI film showed degenerationⅢlevel or above) and 15 cases control group (regardless of gender, average age 30.6 years, disc degeneration observed in the MRI film showed less than degenerationⅡlevel) were fixed, washed, dehydrated, transparent, dipping wax, embedded and sliced. And then we observed the pathology of intervertebral disc degeneration by HE staining and the expression and position of AQP1 and AQP3 in the intervertebral disc for measuring the average optical density. The data collected were statistically analyzed by SPSS 16.0【Results】1. HE staining (1) the control group The structures of disc and collagen fibrins are clear, and the tissue shows mild edema without myxoid denaturation. (2) the case group The structure of disc and collagen fibers are disorderly, and the tissue shows a serious inflammatory edema and myxoid denaturation. Under the background of fibrous cartilage, the number of the active cartilage cells decreases or disappears, and the fibers are thick,dense and degeneration. Within the nucleus pulposus, the increasing cartilage-like cells show nest shape, the fibrins show fibroproliferation and disorganization, and mucus-like substances increase.2. Immunohistochemical staining shows:(1) AQP1 and AQP3 significantly express in the disc in the control group. AQP1 is mainly expressed in the endplate cartilage, nucleus pulposus and inner annulus, and AQP3 also expresses mainly in the cartilage endplate, disc marrow nuclear and inner annulus but expresses scarcely in the outer annulus. (2) The mean optical density value of AQP1 and AQP3 of the case group is less than the control group (the mean optical density of the control group:AQP1 is 0.701±0.424, AQP3 is 0.601±0.323; the mean optical density of the case group:AQP1 is 0.318±0.177, AQP3 is 0.314±0.111).3. Statistical analysis shows that the expression of AQP1 and AQP3 is significantly different between the control group and the case group(P<0.01).[Conclusion] The expression of AQP1 and AQP3 shows significiant difference between the normal disc and the disc degeneration. AQP1 and AQP3 play an important role in the intervertebral disc degeneration and may be one of the initiating factors for the disc degeneration. Inhibiting the decrease of AQP1 and AQP3 may delay the occur of the disc degeneration.