EFFECT OF RENAL DENERVATION ON PLASMA RENALASE CONCENTRATION IN PATIENTS WITH RESISTANT ARTERIAL HYPERTENSION

Objective: Renalase is an enzyme produced among others by proximal tubule cells in the kidneys and participates in the degradation of catecholamine. Results of experimental studies shown that renalase secretion is stimulated by increased plasma catecholamine concentration and by an blood pressure increase. Renal denervation (RDN), i.e., percutaneous ablation of the sympathetic nervous system fibers located in the wall of renal arteries by radio frequency waves, is a method of resistant arterial hypertension treatment. This single-center, interventional clinical study aimed to assess the effect of RDN on the plasma renalase concentration in patients with resistant arterial hypertension. Design and method: Twenty-five patients (12 women, 13 men) aged 54.4 ± 8.1 years with resistant hypertension who underwent renal denervation using Simplicity catheters (Medtronic, Inc., Northridge, CA) were enrolled in the study. Plasma renalase concentration was determined by enzyme-linked immunosorbent assay method (Cloud-Clone Corp., Houston, TX, USA) before RDN, 6 and 12 months after RDN. Results were presented as a mean with standard deviation. Results: Systolic, diastolic blood pressure and heart rate were reduced after RDN (before RDN, 6 and 12 months after RDN, respectively: 190.4 ± 25.0, 161.1 ± 14.7, 155.5 ± 18.3; p<0.001; and 111.8 ± 19.3, 88.9 ± 8.5, 91.0 ± 10.4 mmHg; p<0.001 and 80.1 ± 16.3, 74.5 ± 11.1, 73.6 ± vs. 11.3 beats/min; p<0.001). Plasma renalase concentrations measured before RDN, 6 and 12 months after RDN in the whole studied group were 25.1 ± 7.5, 22.0 ± 7.1, and 23.1 ± 6.0 [μg/mL], respectively (ANOVA p<0.001, Fisher post hoc: before vs. six months p = 0.01, before vs. 12 months p = 0.09, six months vs. 12 months p = 0.3). There were no significant correlations between changes of plasma renalase concentration and decrease of blood pressure and heart rate during the follow-up after RDN. Conclusions: 1. Renal denervation decreases moderate plasma renalase concentration, however this effect of RDN seems to be not associated with observed decrease of blood pressure. 2. Further studies are required to evaluate whether decrease in plasma renalase concentration is associated with change in plasma catecholamine concentration.