糖尿病肾病家兔水通道蛋白及体素内不相干运动磁共振成像参数的研究

Aquaporin-1 and Intravoxel Incoherent Motion MR Imaging in Rabbit Model of Diabetic Nephropathy

目的应用体素内不相干运动(intravoxel incoherent motion,IVIM)磁共振功能成像评价糖尿病肾病家兔肾脏损害,并探讨其与水通道蛋白(aquaporins-1,AQP-1)表达的关系.方法将45只雄性家兔随机分为对照组、1型糖尿病组和2型糖尿病组,并造模.所有家兔均行IVIM成像,计算标准表观扩散系数(SADC)、真实扩散系数(D)、灌注相关扩散系数(D*).应用免疫组织化学方法检测AQP-1在肾脏中的表达;采用单因素方差分析比较3组SADC,D,D*及AQP-1表达的光密度(OD)值;采用Pearson相关分析评价IVIM各参数与AQP-1表达的相关性.结果 1型和2型糖尿病组各参数之间无差异,糖尿病家兔肾皮质、外髓和内髓的D值明显高于对照组(P<0.01),AQP-1的OD值显著高于对照组(P<0.01);AQP-1在肾皮质、外髓和内髓中的表达的OD值与D值呈正相关.结论D值可作为早期检测糖尿病肾脏损害的指标,与AQP-1的表达有关.

Objective To assess kidney damage in rabbit model of diabetic nephropathy based on intravoxel incoherent motion MR imaging( IVIM) and discuss its relationship to the expression of aquaporin-1( AQP-1).Method Forty-five male rabbits were randomly divided into three groups: control group,type 1 diabetes group,type 2 diabetes group. All rabbits were underwent IVIM imaging and calculated the standard apparent diffusion coefficient( SADC value),true diffusion coefficient( D),and perfusion-related diffusion coefficient( D*).The expression of AQP-1 in the kidney was detected by immunohistochemistry.One-way analysis of variance was used to compare SADC,D,D*,and optical density( OD) of AQP-1 expression in the three groups.Pearson correlation analysis was used to evaluate the correlation between the parameters of IVIM and the expression of AQP-1.Results There was no difference between type 1 and type 2 diabetes.D value of renal cortex,outer medulla and inner medulla of diabetic rabbits was significantly higher than that of the control group( P < 0.01). OD value of AQP-1 was significantly higher than that of the control group( P < 0.01). OD value of AQP-1 expression in the renal cortex,the outer medulla and the inner medulla was positively correlated with D value. Conclusion D value can be used as an early indicator of diabetic kidney damage,and is related to the expression of AQP-1.