Article

Nephron Number in Patients with Primary Hypertension

Department of Pathology, University of Heidelberg, Heidelberg, Germany.
New England Journal of Medicine (Impact Factor: 55.87). 01/2003; 348(2):101-8. DOI: 10.1056/NEJMoa020549
Source: PubMed

ABSTRACT

A diminished number of nephrons has been proposed as one of the factors contributing to the development of primary hypertension.
To test this hypothesis, we used a three-dimensional stereologic method to compare the number and volume of glomeruli in 10 middle-aged white patients (age range, 35 to 59 years) with a history of primary hypertension or left ventricular hypertrophy (or both) and renal arteriolar lesions with the number and volume in 10 normotensive subjects matched for sex, age, height, and weight. All 20 subjects had died in accidents.
Patients with hypertension had significantly fewer glomeruli per kidney than matched normotensive controls (median, 702,379 vs. 1,429,200). Patients with hypertension also had a significantly greater glomerular volume than did the controls (median, 6.50x10(-3) mm3 vs. 2.79x10(-3) mm3; P<0.001) but very few obsolescent glomeruli.
The data support the hypothesis that the number of nephrons is reduced in white patients with primary hypertension.

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    • "TABLE 14.1 Estimates of Total Nephron Number for Seven Populations References Population Sample size Mean Range Fold [17] Danish 37 617,000 331,000–1,424,000 4.3 [10] a French 28 1,107,000 655,000–1,554,000 2.4 [35] German 20 1,074,414 531,140–1,959,914 3.7 Hypertensive 10 702,379 531,140–954,893 1.8 Normotensive 10 1,429,200 884,458–1,959,914 2.2 [60] African Americans 105 884,938 210,332–2,026,541 9.6 White Americans 84 843,106 227,327–1,660,232 7.3 [34] "

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