sympathetic nerves run through the adventitia surrounding renal arteries and are critical in the modulation of systemic hypertension . hyperactivity of these nerves can cause renal hypertension , a disease prevalent in 30 - 40 % of the adult population . hypertension can be treated with neuromodulating agents , but requires adherence to strict regimens and often does not reach target blood pressure threshold to reduce risk of major cardiovascular events . a minimally invasive solution is presented here to reduce the activity of the sympathetic nerves surrounding the renal artery by locally delivering neurotoxic or sympathetic nerve - blocking agents into the adventitia . extended elution of these agents may also be accomplished in order to tailor the therapy to the patient .