[HTML][HTML] Sympathetic overactivity in patients with chronic renal failure

RL Converse Jr, TN Jacobsen, RD Toto… - … England Journal of …, 1992 - Mass Medical Soc
RL Converse Jr, TN Jacobsen, RD Toto, CMT Jost, F Cosentino, F Fouad-Tarazi, RG Victor
New England Journal of Medicine, 1992Mass Medical Soc
Background. Hypertension is a frequent complication of chronic renal failure, but its causes
are not fully understood. There is indirect evidence that increased activity of the sympathetic
nervous system might contribute to hypertension in patients with end-stage renal disease,
but sympathetic-nerve discharge has not been measured directly in patients or animals with
chronic renal failure. Methods. We recorded the rate of postganglionic sympathetic-nerve
discharge to the blood vessels in skeletal muscle by means of microelectrodes inserted into …
Background
Hypertension is a frequent complication of chronic renal failure, but its causes are not fully understood. There is indirect evidence that increased activity of the sympathetic nervous system might contribute to hypertension in patients with end-stage renal disease, but sympathetic-nerve discharge has not been measured directly in patients or animals with chronic renal failure.
Methods
We recorded the rate of postganglionic sympathetic-nerve discharge to the blood vessels in skeletal muscle by means of microelectrodes inserted into the peroneal nerve in 18 patients with native kidneys who were undergoing long-term treatment with hemodialysis (of whom 14 had hypertension), 5 patients receiving hemodialysis who had undergone bilateral nephrectomy (of whom 1 had hypertension), and 11 normal subjects.
Results
The mean (±SE) rate of sympathetic-nerve discharge was 2.5 times higher in the patients receiving hemodialysis who had not undergone nephrectomy than in the normal subjects (58±3 vs. 23±3 bursts per minute, P<0.01). In contrast, the rate of sympathetic-nerve discharge was similar in the patients receiving hemodialysis who had undergone bilateral nephrectomy (21±6 bursts per minute) and the normal subjects. The rate of sympathetic-nerve discharge in the patients receiving hemodialysis who had not undergone nephrectomy was also significantly higher (P<0.01) than that in the patients with bilateral nephrectomy, and it was accompanied in the former group by higher values for vascular resistance in the calf (45±4 vs. 22±4 units, P<0.05) and mean arterial pressure (106±4 vs. 76±14 mm Hg, P<0.05). The rate of sympathetic-nerve discharge was not correlated with either plasma norepinephrine concentrations or plasma renin activity.
Conclusions
Chronic renal failure may be accompanied by reversible sympathetic activation, which appears to be mediated by an afferent signal arising in the failing kidneys. (N Engl J Med 1992;327:1912–8.)
The New England Journal Of Medicine