Johnson J E, Barrows C H
Anat Rec. 1980 Feb;196(2):145-51. doi: 10.1002/ar.1091960204.
A study was undertaken to examine, by scanning electron microscopy (SEM), the kidney glomeruli of control mice 1 mo, 10 mo, and 24 mo of age, as well as dietarily restricted mice 10 mo and 24 mo of age. One month old female C57BL/6J mice were offered one of the following: 1) a control diet containing 24% protein fed ad lib; 2) the control diet fed on alternate days (intermittently fed); or 3) a diet containing 4% protein fed ad lib. Animals were sacrificed, by aldehyde perfusion at 1 mo, 10 mo, and 24 mo of age. The kidneys were sliced and prepared for SEM. There was a significant age-related increase in glomerular diameter and amount of microvilli on the podocyte surface (microvillus index). Although the diameters of the podocytes increased approximately 20% with age, these differences were not statistically significant. Feeding a 4% protein diet resulted in smaller diameters of glomeruli and podocytes as well as smaller microvilli indices as compared to those of control animals. Although similar differences were observed in the kidneys of intermittently fed animals, only the microvillus index was statistically significant. Therefore, dietary manipulations, which have been shown to increase life span, result in marked morphological differences when compared to control animals.
开展了一项研究，通过扫描电子显微镜（SEM）检查1月龄、10月龄和24月龄对照小鼠以及10月龄和24月龄饮食限制小鼠的肾小球。给1月龄雌性C57BL/6J小鼠提供以下之一的饮食：1）含24%蛋白质的对照饮食，随意进食；2）对照饮食隔天喂食（间歇性喂食）；或3）含4%蛋白质的饮食，随意进食。在1月龄、10月龄和24月龄时通过醛灌注法处死动物。将肾脏切片并制备用于SEM观察。肾小球直径和足细胞表面微绒毛数量（微绒毛指数）随年龄增长有显著增加。尽管足细胞直径随年龄增长增加约20%，但这些差异无统计学意义。与对照动物相比，喂食含4%蛋白质饮食的小鼠肾小球和足细胞直径更小，微绒毛指数也更小。尽管在间歇性喂食动物的肾脏中观察到类似差异，但只有微绒毛指数具有统计学意义。因此，已证明能延长寿命的饮食干预与对照动物相比会导致明显的形态学差异。
