Brain BOLD fMRI in Hypertensive and Normotensive Participants

Overview

This study will explore the brainstem activity in response to stress in hypertensive patients and normotensive subjects. In addition, it will evaluate if the response in hypertensive patients can be modulated by blocking the afferent signalling of sympathetic nervous system from the kidney to the brain achieved by renal denervation. The investigators hypothesize that the change in BOLD signal intensity in response to stress is higher in hypertensive patients than in normotensive subjects and that in patients responsive to renal denervation the change in BOLD signal intensity in response to stress is decreased compared to non-responders or to non-denervated resistant hypertensive patients.

In hypertension, the overactivity of the sympathetic nervous system (SNS) has been found to be implicated in its initiation, maintenance and adverse consequences. The SNS is composed of an afferent and efferent arm, which brings sensory information to the brain (e.g. brainstem and hypothalamus) and transmits sympathetic outflow from the brain to the peripheral organs, respectively. Selective removal of the afferent renal component of the SNS can modulate central sympathetic outflow to the kidney, heart and vasculature in animals. The specific contribution of afferent nerve signalling in hypertension and in the potential antihypertensive effect of renal denervation has not been studied in humans.

Conditions

Interventions