Erythrocyte membranes beta-adrenoreactivity changes after renal denervation in patients with resistant hypertension, relationship with antihypertensive and cardioprotective intervention efficacy

Aim To study the functional condition of sympathoadrenal system as evaluated by beta-adrenoreactivity of erythrocyte membranes (beta-ARM) during two years following renal denervation (RD) in patients with resistant arterial hypertension (RAH) and to determine the relationship of this index with long-term antihypertensive and cardioprotective effectivity of this invasive treatment. Material and methods The study included 48 patients (mean age, 57.2±8.7 years, 18 men) with RAH on a stable antihypertensive therapy. Averaged daily systolic and diastolic blood pressure (SBP and DBP) and levels of beta-ARM were determined at baseline and in 7 days and 2 years following RD. Measurement of beta-ARM was based on beta-adrenoblocker inhibition of erythrocyte hemolysis induced by exposure to hypo-osmotic environment. The beta-adrenoblocker binds to erythrocyte membrane beta-adrenoceptors to prevent the erythrocyte destruction. Increased values of beta-ARM reflect a decrease in the number of functionally active erythrocyte membrane beta-adrenoceptors associated with long-term sympathetic hyperactivity. Results For two years of follow-up, values of average daily BP decreased from 160.4±16.0 / 88.1±14.6 to 145.3±19.3 / 79.4±13.6 mm Hg. At 7 days, the number of beta-ARM had decreased in the group of RD responders (р=0.028) who at two years had decreased their BP by 10 mm Hg or more, while in the group of non-responders, the number of beta-ARM remained unchanged. At one week, beta-ARM values correlated with changes in SBP and DBP (r= –0.54; р<0.05) and with left ventricular myocardial mass (LVMM) (r= –0.36; р<0.05) at two years of follow-up whereas beta-ARM delta at one week was interrelated with the renin concentration in the long-term (r= –0.44; р<0.05). At two years, the content of beta-ARM was increased in both groups. Conclusion The decrease in beta-ARM content at 7 days after RD shows the procedure efficacy and allows an expectation of clinically significant decreases in BP and LVMM in the long-term after the surgical treatment. At two years after the intervention, the content of beta-ARM increased, and the BP decrease was apparently due to some other mechanisms.