Hoy Wendy E, Douglas-Denton Rebecca N, Hughson Michael D, Cass Alan, Johnson Kelli, Bertram John F
Renal Unit, Menzies School of Health Research, Darwin, Northern Territory, Australia.
Kidney Int Suppl. 2003 Feb(83):S31-7. doi: 10.1046/j.1523-1755.63.s83.8.x.
This report describes preliminary results of a study of glomerular number and volume and their associations, in kidneys of people coming to autopsy.
Both kidneys were weighed at autopsy and the right kidney was perfusion-fixed and sub-sampled for stereological estimation of total glomerular number, and of mean renal corpuscle volume, using the physical disector/fractionator combination.
The 78 kidneys studied so far were from Australian Aborigines, Australian non-Aborigines, US blacks and US whites, ages newborn to 84 years. Glomerular number ranged almost ninefold (from 210,332 to 1,825,380), with mean (SD) of 784,909 (314,686); it decreased throughout adult life (r=-0.32, P=0.009). Mean renal corpuscle volume varied 5.6-fold in adults and was inversely correlated with glomerular number (r=-0.38, P=0.001). Total renal corpuscle volume varied in adults by a factor of 15.8. Kidney weight correlated with body surface area (BSA) at all ages (r=0.76, P < 0.001); it varied 3.4-fold among adults, while kidney weight/m2 varied 3.7-fold. The percentage of sclerosed glomeruli varied from 0 to 23%, and it correlated strongly with age (r=0.58, P < 0.001). Females had smaller kidneys than males, and, marginally, fewer glomeruli. There were no significant variations by ethnic group.
These extraordinary ranges of glomerular number and size among ostensibly "normal" people, and their inverse relationship, probably have important implications for susceptibility to renal insufficiency. People with low glomerular (nephron) numbers are likely to be particularly predisposed, with the process marked by compensatory hypertrophy of residual nephrons, which, in turn, accelerates their obsolescence. Much, however, remains to be done, including evaluation of history, clinical features, accompanying pathology, detailed renal morphology, and further pursuit of potentially defining characteristics in high risk groups.
本报告描述了一项针对尸检者肾脏中肾小球数量和体积及其相关性研究的初步结果。
尸检时对双侧肾脏称重，对右肾进行灌注固定，并使用物理分割器/分样器组合对其进行亚取样，以进行肾小球总数和平均肾小体体积的体视学估计。
迄今研究的78个肾脏来自澳大利亚原住民、澳大利亚非原住民、美国黑人和美国白人，年龄从新生儿到84岁。肾小球数量范围几乎相差9倍（从210,332个到1,825,380个），平均（标准差）为784,909个（314,686个）；在整个成年期肾小球数量均减少（r = -0.32，P = 0.009）。成年期平均肾小体体积相差5.6倍，且与肾小球数量呈负相关（r = -0.38，P = 0.001）。成年期肾小体总体积相差15.8倍。肾脏重量在各年龄段均与体表面积（BSA）相关（r = 0.76，P < 0.001）；成年期肾脏重量相差3.4倍，而每平方米肾脏重量相差3.7倍。硬化肾小球的百分比从0%到23%不等，且与年龄密切相关（r = 0.58，P < 0.001）。女性的肾脏比男性小，肾小球数量略少。不同种族之间无显著差异。
在表面上“正常”的人群中，肾小球数量和大小存在如此大的差异范围，以及它们之间的负相关关系，可能对肾功能不全的易感性具有重要意义。肾小球（肾单位）数量低的人可能特别容易患病，其过程以残余肾单位的代偿性肥大为特征，这反过来又加速了它们的衰老。然而，仍有许多工作要做，包括对病史、临床特征、伴随的病理学、详细的肾脏形态学进行评估，以及进一步探究高危人群中潜在的决定性特征。
