Wallace D P, Hou Y-P, Huang Z L, Nivens E, Savinkova L, Yamaguchi T, Bilgen M
The Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas 66160-3018, USA.
Kidney Int. 2008 Mar;73(6):778-81. doi: 10.1038/sj.ki.5002771. Epub 2008 Jan 9.
Polycystic kidney disease is characterized by the progressive enlargement of kidneys due to expanding fluid-filled cysts with the rate of renal volume increase held to be a marker of disease progression. Magnetic resonance imaging (MRI) is used to monitor changes in renal volume in patients with polycystic kidney disease; however, it has not been effectively used in mice to monitor changes in kidney volume during drug treatment studies. We used a powerful 9.4-T horizontal bore magnetic resonance scanner to track changes in kidney volume in pcy/pcy mice, an ortholog of nephronophthisis type 3. Mice were sequentially scanned from 4 to 30 weeks of age and kidney volumes determined from high-resolution images. Kidney volume and maximal cross-sectional surface area correlated positively with kidney weight and the histologic determination of surface area. The increase in kidney volume was exponential up to 20 weeks of age, after which there was a plateau consistent with the replacement of normal parenchyma by fibrotic tissue. Our study demonstrates that MRI accurately determines the rate of kidney volume increase in mice with polycystic kidney disease and hence may be useful in assessing the effectiveness of therapeutic agents to slow disease progression.
多囊肾病的特征是由于充满液体的囊肿不断扩大，导致肾脏逐渐增大，肾脏体积增加的速率被认为是疾病进展的一个标志。磁共振成像（MRI）用于监测多囊肾病患者肾脏体积的变化；然而，在药物治疗研究中，它尚未有效地用于小鼠肾脏体积变化的监测。我们使用一台强大的9.4-T水平孔径磁共振扫描仪来追踪pcy/pcy小鼠（3型肾痨的直系同源物）肾脏体积的变化。从4周龄到30周龄对小鼠进行连续扫描，并从高分辨率图像中确定肾脏体积。肾脏体积和最大横截面积与肾脏重量以及表面积的组织学测定呈正相关。直到20周龄，肾脏体积的增加呈指数增长，之后出现平台期，这与正常实质被纤维组织取代一致。我们的研究表明，MRI能够准确测定多囊肾病小鼠肾脏体积增加的速率，因此可能有助于评估治疗药物减缓疾病进展的有效性。
