Renal nerves in the maintenance of hypertension: a potential therapeutic target.

Renal sympathetic efferent and afferent nerves, which lie within and immediately adjacent to the wall of the renal arteries, contribute to the maintenance of hypertension. Because the causative factors of hypertension change over time, denervation of both efferent and afferent renal nerves should result in long-term attenuation of hypertension. The importance of the renal nerves in hypertensive patients can now be defined with the novel development of percutaneous, minimally invasive renal denervation from within the renal artery using radiofrequency energy as a therapeutic strategy. Studies thus far show that catheter-based renal denervation in patients with resistant essential hypertension lowers systolic blood pressure 27 mm Hg by 12 months, with the estimated glomerular filtration rate remaining stable. The decrease in arterial pressure after renal denervation is associated with decreased peripheral sympathetic nervous system activity, suggesting that the kidney is a source of significant central sympathetic outflow via afferent renal nerve activity.