INVIVO NMR IMAGING AND SPECTROSCOPIC INVESTIGATION OF RENAL PATHOLOGY IN LEAN AND OBESE RAT KIDNEYS
INVIVO NMR IMAGING AND SPECTROSCOPIC INVESTIGATION OF RENAL PATHOLOGY IN LEAN AND OBESE RAT KIDNEYS
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DOI：
10.1002/mrm.1910290309
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发表时间：
1993-03-01
影响因子：
3.3
通讯作者：
SHALWITZ, RA
中科院分区：
文献类型：
--
作者：
BOSCH, CS;ACKERMAN, JJH;SHALWITZ, RA
糖尿病肾病是终末期肾功能衰竭的主要原因。虽然我们对肾病发病机制的了解尚不完整，但进行性肾小球损伤似乎在肾功能下降中起着重要作用。质子核磁共振波谱和成像技术用于研究自发性肥胖和瘦（对照）Zucker大鼠体内肾脏肾小球系膜扩张相关的肾脏病理变化。完全功能的大鼠肾脏通过手术暴露并外化，通过放置在器官周围的线圈直接进行核磁共振信号检测。在4.7 T磁场强度下获得高分辨率（78 μm平面）质子图像，显示皮层和髓质区域内清晰的精细结构。肥胖大鼠肾脏图像在外观上与瘦肾图像不同，表现出明显的皮质扩张以及肾脏整体大小的增加。与瘦肾相比，肥胖肾的平均肾小球直径增大。质子t1和t2松弛时间使用标准光谱技术从整个肾脏确定，并从肾脏内的特定区域通过多重t1和t2加权图像确定。此外，利用磁化转移成像技术，研究了瘦肉大鼠和肥胖大鼠肾脏中受限移动环境中的质子与肾脏内移动的水质子之间的饱和转移所导致的图像对比度增强。在本研究检查的肾脏损伤早期，仅根据松弛时间不能区分病变肾脏和健康肾脏。在瘦肾和肥胖肾的皮质组织中获得的饱和转移的大小也没有统计学上的显著差异。然而，在肥胖肾脏髓质组织中实现的饱和转移幅度在统计学上明显小于瘦肾。
Diabetic nephropathy is a major cause of end‐stage renal failure. While our understanding of the pathogenesis of nephropathy is incomplete, progressive glomerular injury appears to play a significant role in the decline of renal function. Proton NMR spectroscopy and imaging techniques were used to address changes in renal pathology associated with glomerular mesangial expansionin vivoin kidneys from spontaneously obese and lean (control) littermate Zucker rats. Fully functioning rat kidneys were surgically exposed and externalized for direct NMR signal detection via a coil placed around the organ. High‐resolution (78 μm in plane) proton images were obtained at 4.7 T magnetic field strength revealing fine structure within the well‐defined cortical and medullary regions. The obese rat kidney images were distinct in appearance from the lean kidney images and exhibited marked cortical expansion as well as increased overall kidney size. Enlargement of mean glomerular diameter was verified histologically in the obese kidneys as compared with the lean kidneys. ProtonT1andT2relaxation times were determined from the entire kidney using standard spectroscopic techniques, and from specific regions within the kidney from multipleT1andT2‐weighted images. Additionally, image contrast enhancement resulting from saturation transfer between protons in restricted‐mobility environments and mobile water protons within the kidney was investigated in the lean and obese rat kidneys using magnetization‐transfer imaging techniques. At the early stage of renal injury examined in this study, diseased and healthy kidneys could not be differentiated on the basis of relaxation times alone. The magnitude of saturation transfer obtained in cortical tissue in the lean and obese kidneys was also not statistically significantly different. However, the magnitude of saturation transfer achieved in the medullary tissue of obese kidneys was statistically significantly less than that achieved in lean kidneys.