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Updated: Jul 19, 2026
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Quantifying Acute Changes in Renal Sympathetic Nerve Activity in Response to Central Nervous System Manipulations in Anesthetized Rats
Published on: September 11, 2018
Decrease in peripheral sympathetic nervous system activity following renal denervation or unclipping in the
The Journal of Clinical Investigation
|January 1, 1982
Summary
Renal denervation and unclipping significantly lower blood pressure in hypertensive rats by reducing sympathetic nervous system activity. This study highlights the role of the sympathetic nervous system in one-kidney one-clip hypertension.
Area of Science:
- Nephrology
- Cardiovascular Physiology
- Hypertension Research
Background:
- One-kidney, one-clip hypertension in rats is associated with increased sympathetic nervous system activity.
- Previous studies showed renal denervation attenuates hypertension without affecting sodium, water, or renin levels.
Purpose of the Study:
- To investigate if the blood pressure-lowering effect of renal denervation in one-kidney, one-clip hypertensive rats is linked to peripheral sympathetic nervous system activity changes.
- To compare the effects of renal denervation and unclipping on blood pressure and sympathetic activity.
Main Methods:
- One-kidney, one-clip hypertension was induced in rats.
- Groups underwent sham operation, renal denervation, or unclipping.
- Plasma norepinephrine levels and mean arterial pressure response to ganglionic blockade were measured as indicators of sympathetic activity.
Main Results:
- Renal denervation significantly decreased systolic blood pressure (201 to 151 mm Hg).
- Unclipping normalized blood pressure (to 130 mm Hg).
- Plasma norepinephrine levels were reduced to normal in both denervated and unclipped rats compared to hypertensive controls. Ganglionic blockade caused a greater pressure drop in hypertensive rats, indicating higher sympathetic tone.
Conclusions:
- The blood pressure-lowering effects of renal denervation and unclipping in this hypertension model are associated with a reduction in peripheral sympathetic nervous system activity.
- Renal denervation offers a potential therapeutic strategy for hypertension by modulating sympathetic tone.
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