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Related Experiment Video

Updated: Jun 17, 2026

Estimation of Nephron Number in Whole Kidney using the Acid Maceration Method

Estimation of Nephron Number in Whole Kidney using the Acid Maceration Method

Published on: May 22, 2019

Urinary concentration and dilution in the aging kidney.

¹Renal Division, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA. jsands@emory.edu

Seminars in Nephrology

|December 17, 2009

Summary

Aging reduces the kidney

Area of Science:

Nephrology
Gerontology
Molecular Biology

Background:

Aging is associated with a diminished capacity for maximal urine concentration.
Reduced kidney function in older individuals impacts water balance and overall health.

Purpose of the Study:

To investigate the molecular mechanisms underlying age-related decline in urine concentrating ability in rats.
To identify key transport proteins affected by aging in the renal medulla.

Main Methods:

Comparative analysis of renal medulla protein abundance in aged versus young rats.
Assessment of protein response to water restriction in different age groups.

Main Results:

Aged rats exhibit reduced levels of key water, sodium, and urea transport proteins in the renal medulla.

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Last Updated: Jun 17, 2026

Estimation of Nephron Number in Whole Kidney using the Acid Maceration Method

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5/6th Nephrectomy in Combination with High Salt Diet and Nitric Oxide Synthase Inhibition to Induce Chronic Kidney Disease in the Lewis Rat

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These protein reductions are less responsive to water restriction in aged rats.

This molecular deficit contributes to impaired urine concentration and water conservation in aging.

Conclusions:

Reduced abundance and responsiveness of transport proteins in the renal medulla are key factors in age-related decline of urine concentrating ability.
These findings in rats suggest potential molecular targets for therapeutic interventions in humans.
Understanding these mechanisms could lead to novel treatments for impaired kidney function in the elderly.