透镜诱导型近视肾阳虚豚鼠巩膜MMP-2及其抑制剂TIMP-2的表达

目的　探讨负透镜诱导型近视肾阳虚豚鼠巩膜基质金属蛋白酶２（ｍａｔｒｉｘｍｅｔａｌ-ｌｏｐｒｏｔｅｉｎａｓｅ-２，ＭＭＰ-２）及其抑制剂基质金属蛋白酶-２抑制剂（ｔｉｓｓｕｒｅｉｎｈｉｂｉｔｏｒｏｆｍｅｔａｌｌｏｐｒｏ-ｔｅｉｎａｓｅ-２，ＴＩＭＰ-２）的表达。方法　选取７２只３周龄雄性英国种三色短毛豚鼠，随机分为正常对照组、戴镜组和肾阳虚＋戴镜组，每组各２４只。肾阳虚＋戴镜组每日腹腔注射氢化可的松注射液，剂量１０ｍｇ·ｋｇ－１，正常对照组和戴镜组则给予等量生理盐水，每天１次，连续２周。第３周起，戴镜组、肾阳虚＋戴镜组右眼均戴－１０．０Ｄ透镜，戴镜２周，正常对照组不作任何干预。戴镜前后分别进行眼轴长度及屈光度的测量；ＳＹＢＲｇｒｅｅｎＩ实时荧光定量ＰＣＲ检测后极部巩膜ＭＭＰ-２及ＴＩＭＰ-２ｍＲＮＡ的表达变化；ＥＬＩＳＡ和免疫组织化学检测后极部巩膜ＭＭＰ-２及ＴＩＭＰ-２蛋白表达的变化。结果　与正常对照组比较，戴镜组右眼近视屈光度增高（ｔ＝１８．７６０，Ｐ＝０．０００），眼轴延长（ｔ＝－２．７０９，Ｐ＝０．０１３），后极部巩膜ＭＭＰ-２ｍＲＮＡ及蛋白表达明显增加（ｔ＝－２．１３４，Ｐ＝０．０４５；ｔ＝－６．３１５，Ｐ＝０．０００），ＴＩＭＰ-２ｍＲＮＡ及蛋白表达明显降低（ｔ＝４．６３７，Ｐ＝０．０００；ｔ＝６．０６２，Ｐ＝０．０００）。与戴镜组比较，肾阳虚＋戴镜组右眼近视屈光度增高（ｔ＝３．０２６，Ｐ＝０．００６），眼轴更长（ｔ＝－２．１４４，Ｐ＝０．０４４），后极部巩膜ＭＭＰ-２ｍＲＮＡ及蛋白表达均增加（ｔ＝－４．０９４，Ｐ＝０．００１；ｔ＝－６．２９１，Ｐ＝０．０００），ＴＩＭＰ-２ｍＲＮＡ及蛋白表达均降低（ｔ＝５．５２４，Ｐ＝０．０００；ｔ＝３．９５１，Ｐ＝０．００１）。结论　在负透镜诱导下，肾阳虚豚鼠较正常豚鼠近视程度更加严重，肾阳虚体质与近视的发生发展可能有密切联系。

Expression of MMP-2 and its inhibitor TIMP-2 in sclera of Kidney-Yang Deficiency syndrome myopic guinea pigs induced by lens

Objective To explore the expression of matrix metalloproteinase-2 ( MMP-2 ) and tissue inhibitor of metalloproteinase-2 ( TIMP-2 ) in posterior sclera of lens-induced myopic guinea pigs with Kidney-Yang Deficiency syndrome ( KYDs ) . Methods Seventy-two three-week-old male pigmented grinea pigs were randomly divided into the normal group , wearing lens group ( WL group ) , and KYDs and wearing lens group ( KYDs + WL group ) , 24 cases in each group. The KYDs + WL group was intraperitoneally injected hydrocortisone with a does of 10 mg ’ kg-’, while the normal group and WL group were treated with isodose saline at the same time once daily for 2 weeks. Since the third week , the right eyes of the WL group and KYDs + WL group were covered with - 10. 0 D lens for 2 weeks.while the both eyes of normal group were without any intervention. The refraction and axial length were measured before and after wearing lens. The expressions of MMP-2 and TIMP-2 in posterior sclera were assayed by real-time PCR , ELISA and immunohistochemistry. Results Compared with the normal group , the myopic diopters were increased ( t = 18. 760 .P = 0. 000 ) , and the axial lengths were longer( t = -2. 709 ,P = 0. 013) . and the expressions of MMP-2 were increased at both the gene and protein levels ( t = - 2. 134 ,P = 0. 045 ; t = - 6. 315 ,P = 0. 000 ) . and the expressions of TIMP-2 were decreased at both the gene and protein levels in the WL group ( t = 4. 637 .P = 0. 000 ; t = 6. 062 ,P = 0. 000 ) . Compared with the WL group , the myopic diopters were higher( t = 3. 026 ,P = 0. 006 ) . and the axial lengths were longer ( t = - 2. 144 .P = 0. 044) . and the expressions of MMP-2 were increased at both the gene and protein levels( t = - 4. 094 .P = 0. 001 ; t = - 6. 291 ,P = 0. 000 ) , and the expressions of TIMP-2 were decreased at both the gene and protein levels in KYDs + WL group ( t = 5. 524 ,P = 0. 000 ; t = 3. 951 .P = 0. 001 ) . Conclrision Under the induction of lens . the eyes of KYDs guinea pigs tend to be more myopic than that of normal guinea pigs. The Kidney-Yang Deficiency constitution is probably associated with the occurrence and development of myopia.