4A.04: EFFECTS OF RENAL DENERVATION ON ASYMMETRIC DIMETHYLARGININE AND SYMPATHETIC NERVE TRAFFIC IN RESISTANT HYPERTENSIVE PATIENTS. (June 2015) - Seravalle, G.
Abstract : Objective: Plasma concentrations of the endogenous inhibitor of nitric oxide synthase asymmetric dimethyl arginine (ADMA) are associated with sympathetic activity in patients with chronic disease. The driver of this association remains unknown. To solve the question it has been used the renal denervation of resistant hypertensive patients due to the marked reduction in whole-body norepinephrine spillover and sustained decrease in sympathetic nerve traffic (MSNA), thus representing an unique model to examine the hypothesis that sympathetic activity modulates circulating ADMA and its symmetric enantiomer (SDMA). Design and method: 14 true resistant hypertensives (ESH/ESC guidelines definition) were evaluated at baseline and 15, 30, 90, 180 days after renal denervation. In each session blood samples were taken and then we measured beat-to-beat finger blood pressure (BP, Finapres), heart rate (HR), MSNA (microneurography). The global relationship between MSNA vs ADMA and SDMA was based on the calculation of the areas under the curves of these variables after renal denervation. Regression analyses were then performed. Results: After renal denervation we observed a reduction in MSNA of -17% (range: from -66% to +10%). Changes in MSNA were strongly associated with the corrisponding changes in plasma ADMA (r = 0.69, p = 0.005) and SDMA (r = 0.87, p < 0.001). Furthermore, changes in MSNA went along with simultaneous changes in systolic (r = 0.79, p = 0.001) and diastolic BP (r = 0.82, p < 0.001) and HR (r = 0.68, p < 0.01). All these relationships were largerly independent of renal dysfunction. Conclusions: These observations are compatible with the hypothesis that the sympathetic nervous system exerts an important role in modulating circulating levels of ADMA and SDMA in this condition.