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Updated: Jun 4, 2026
08:50
5/6th Nephrectomy in Combination with High Salt Diet and Nitric Oxide Synthase Inhibition to Induce Chronic Kidney Disease in the Lewis Rat
Published on: July 3, 2013
Nycthemeral relationship between renal function and sodium homeostasis.
1Department of Medicine, University Hospital Maastricht, PO Box 5800, 6202, AZ, Maastricht, The Netherlands. p.deleeuw@maastrichtuniversity.nl
Current Hypertension Reports
|February 8, 2011
Summary
The kidney
Area of Science:
- Nephrology and Chronobiology
Background:
- Nycthemeral (daily) variations in renal function are well-documented.
- The precise physiological mechanisms driving these daily changes in kidney function, particularly sodium handling, remain incompletely understood.
Purpose of the Study:
- To explore the physiological systems potentially responsible for the kidney's transition from sodium excretion during the day to sodium conservation at night.
- To evaluate the roles of pressure natriuresis and glomerular filtration rate in nycthemeral sodium output variations.
Main Methods:
- Review of existing physiological and molecular studies on renal function and circadian rhythms.
- Analysis of the relationship between blood pressure, glomerular filtration rate, and sodium excretion patterns.
Main Results:
- Evidence suggests pressure natriuresis alone does not fully explain daily sodium output cycles in intact humans.
- While glomerular filtration rate shows nocturnal variation, its amplitude mismatch with sodium excretion implies it's not the sole driver.
- Data support the involvement of tubular mechanisms, particularly in the distal nephron, in regulating daily sodium balance.
Conclusions:
- Circadian gene products are identified as potential regulators of the renal sodium excretory rhythm.
- Tubular mechanisms, especially in the distal nephron, are likely key to daily sodium conservation and excretion patterns.
- Further research into molecular mechanisms is needed to fully elucidate the control of nycthemeral renal function.
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