Mild chronic renal insufficiency induces sympathetic overactivity

Abstract

The objectives of this study were to evaluate baseline sympathetic nerve activity as well as the mechanisms of sympathetic overactivity in mild chronic renal insufficiency hypertension. Seven hypertensives with mild renal insufficiency, seven hypertensives with normal renal function and seven normotensives, age and weight-matched were studied on one session to evaluate baseline muscle sympathetic nerve activity measured in the peroneal nerve. The mild renal insufficiency hypertensives and the hypertensives with normal renal function were also studied to evaluate arterial baroreflex control of muscle sympathetic nerve activity assessed by increasing and decreasing blood pressure through continuous infusion of phenylephrine and sodium nitroprusside respectively. Baseline muscle sympathetic nerve activity was significantly higher in mild renal insufficiency hypertensives (34 bursts/min) when com-

Ultradian but not Circadian Blood Pressure Rhythms Correlate with Renal Dysfunction in Children with Chronic Renal Failure

“…Although this question has not been addressed systematically, it is tempting to speculate on several pathophysiologic possibilities. Muscle sympathetic nerve activity, for example, correlates with daytime BP variability in healthy men (8), and sympathetic nerve overactivity is a hallmark of CRF that occurs early in the course of disease (13). Irregular BP fluctuations caused by an increased sympathetic nervous tone may cause increased "noise" in the dynamic BP patterns, which may lead to apparently blunted amplitudes of the physiologic regular ultradian oscillations of BP.…”

“…As the importance of the neuroendocrine origins of hypertension in early CRF are increasingly understood (12,13), it is tempting to speculate that abnormalities in the sympathetic tone could affect not only circadian and minute-to-minute fluctuations of BP and HR but also ultradian cardiovascular rhythmicity even in mild to moderate renal failure. Such potential abnormalities may be more readily detectable in children, in whom ultradian rhythms seem to be more prominent than in adults (10).…”

Proof of concept study: Improvement of echocardiographic parameters after renal sympathetic denervation in CKD refractory hypertensive patients - diastolic function

“…In CKD, the sympathetic hyperactivity seems to be expressed at the earliest clinical stage of the disease, showing a direct relationship with the severity of the condition of renal impairment [13][14][15][16][17]. The interruption of sympathetic hyperactivity and feedback of the renin-angiotensinaldosterone system cycle may be beneficial for this population.…”

Electroacupuncture and Moxibustion Decrease Renal Sympathetic Nerve Activity and Retard Progression of Renal Disease in Rats

“…In this respect, hypertension can be a cause of and a sustaining and worsening factor in the progression of renal disease. Evidence is accumulating that activation of the sympathetic nervous system (SNS) could play a major role in the progression of CKD [15,16]. Enhanced activity of the SNS has been demonstrated in patients with CKD [16,17].…”