正常和肾积水胎儿肾脏水通道蛋白1-3的表达

目的 探讨正常和肾积水胎儿肾脏水通道蛋白1-3(AQP1-3)在孕中、晚期表达的差异.方法 收集本院母亲身体健康,因其他原因而引产的21例正常胎儿(孕中期12例,孕晚期9例)和9例孕晚期肾积水胎儿肾脏标本;应用免疫组织化学方法检测各组肾脏AQP1-3的定位与表达.同时采用Westem Blot检测正常和肾积水胎儿肾脏AQP1-3蛋白表达水平.同期收集本院8例成人因肾癌行肾切除术远离肿瘤的正常肾脏组织作为AQP1-3表达阳性对照.结果 免疫组化结果显示AQP1阳性染色主要分布于肾小球毛细血管内皮细胞、近曲小管的上皮细胞及髓袢降支细段上皮细胞胞质;AQP2阳性染色主要分布于肾脏集合管上皮细胞胞膜和胞质;AQP3阳性染色主要分布于肾脏集合管主细胞的基底侧.经Image-Pro Plus图像分析软件统计分析,孕中期肾脏AQP1-3表达分别为0.375±0.056、0.278±0.031和0.312±0.050,均弱于孕晚期组(分别为0.483±0.062、0.356±0.048和0.501±0.068),肾积水组AQP1-3表达分别为0.308±0.051、0.247±0.039和0.282±0.056,也均弱于同孕期正常胎儿,且胎儿肾脏AQP1-3表达均弱于成人对照组(分别为0.626±0.084、0.432±0.049和0.687±0.058,P＜0.05).Western Blot同样显示正常孕晚期胎儿AQP1-3蛋白表达量(0.96±0.07、0.94±0.06和0.95±0.05)显著高于孕中期(0.82±0.05、0.76±0.04和0.79±0.04),且高于同孕期肾积水组表达量(0.54±0.04、0.42±0.03和0.53±0.04,P＜0.05).结论 胎儿积水肾脏AQP1-3的表达水平较正常胎儿明显降低提示胎儿积水肾脏浓缩稀释功已经受损.

Expressions of aquaporin 1-3 in normal and hydronephrotic fetal kidneys

Objective To explore the differential expressions of aquaporin 1-3 in normal and hydronephrotic fetal kidney.Methods Thirty cases of aborted fetal kidneys were collected from healthy mothers and diagnosed as normal or hydronephrosis by urinary ultrasound.Among them,21 were normal (second trimester,n =12;third trimester,n =9) while the remainder belonged to hydronephrosis (third trimester,n =9).Meanwhile,8 cases of adult normal kidney tissues adjacent to carcinoma were collected as positive controls.Immunohistochemistry and Western bolt were used for examining the locations and expressions of aquaporin 1-3 in kidney.Results Immunohistochemistry showed that AQP1-positive staining was predominantly distributed in glomerular capillary endothelial cells,oroximal convoluted tubule epithelial cells and epithelial cells of descending thin myelin loops;AQP2-positive staining was predominantly located in renal collecting duct epithelial cell membrane and cytoplasm;AQP3-positive staining was predominantly distributed in basal principal cells of renal collecting duct.Analysis of Image-Pro plus software showed that renal AQP1-3 expressions in second trimesters were weaker than those in third trimesters (0.375 ± 0.056 vs 0.483 ± 0.062,0.278 ± 0.031 vs 0.356 ± 0.048,0.312 ± 0.050 vs 0.501 ± 0.068) and the expressions in hydronephrotic kidney were (0.308 ± 0.051,0.247 ± 0.039 & 0.282 ±-0.056) lower than those in normal kidney of the same trimesters.And the above results were confirmed by Western blot.The expressions of AQP1-3 in second and third trimesters and hydronephrotic fetus kidney were 0.82 ± 0.05 vs 0.96 ± 0.07 vs 0.54 ±0.04,0.76±0.04 vs 0.94±0.06 vs 0.42±0.03 and 0.79±0.04 vs 0.95 ±0.05 vs 0.53-±0.04 respectively.Conclusions The expressions of AQP1-3 in fetal kidney increase with gestational age.And a lower expression of AQP1-3 implies that renal function has changed in fetal hydronephrotic kidney.