Renal Sympathetic Hyperactivity in Hypertension: True or False? To the Editor: Increased renal norepinephrine spillover, observed by using isotope-dilution method, is thought to indicate renal sympathetic hyperactivity and to play a crucial role in hypertension. However, SYMPLICITY HTN-3 (Renal Denervation in Patients With Uncontrolled Hypertension), the first randomized shamcontrolled trial, f...

Renal Sympathetic Hyperactivity in Hypertension: True or False? To the Editor: Increased renal norepinephrine spillover, observed by using isotope-dilution method, is thought to indicate renal sympathetic hyperactivity and to play a crucial role in hypertension. However, SYMPLICITY HTN-3 (Renal Denervation in Patients With Uncontrolled Hypertension), the first randomized shamcontrolled trial, f...

Renal Sympathetic Hyperactivity in Hypertension: True or False? To the Editor: Increased renal norepinephrine spillover, observed by using isotope-dilution method, is thought to indicate renal sympathetic hyperactivity and to play a crucial role in hypertension. However, SYMPLICITY HTN-3 (Renal Denervation in Patients With Uncontrolled Hypertension), the first randomized shamcontrolled trial, f...

Renal Sympathetic Hyperactivity in Hypertension: True or False? To the Editor: Increased renal norepinephrine spillover, observed by using isotope-dilution method, is thought to indicate renal sympathetic hyperactivity and to play a crucial role in hypertension. However, SYMPLICITY HTN-3 (Renal Denervation in Patients With Uncontrolled Hypertension), the first randomized shamcontrolled trial, f...

Renal Sympathetic Hyperactivity in Hypertension: True or False? To the Editor: Increased renal norepinephrine spillover, observed by using isotope-dilution method, is thought to indicate renal sympathetic hyperactivity and to play a crucial role in hypertension. However, SYMPLICITY HTN-3 (Renal Denervation in Patients With Uncontrolled Hypertension), the first randomized shamcontrolled trial, f...

The acute responsiveness of plasma catecholamine, renin (PRA), and aldosterone levels to exogenous norepinephrine was studied under placebo conditions and following renin (PRA), and aldosterone levels to exogenous norepinephrine was studied under placebo conditions and following renin-angiotensin activation by diuretic pretreatment in 25 normal subjects and 34 patients with borderline-to-modera...

We infused tracer-labeled l-[3H]-norepinephrine, d-[14C]norepinephrine, and d,l-[3H]-isoproterenol simultaneously into patients with essential hypertension and into normotensive control subjects, in order to determine whether abnormalities in the disappearance kinetics of these substances characterized the hypertensive patients. The mean preinfusion venous plasma norepinephrine concentration wa...

Levels of synaptic cleft norepinephrine associated with pressor responses were estimated in humans by measuring blood pressure and arterial plasma norepinephrine during norepinephrine infusion and during yobimbine-induced release of endogenous norepinephrine. Linear pressor response-log norepinephrine concentration relationships were observed during the infusions. At a pressor response of 20 mm...

Levels of synaptic cleft norepinephrine associated with pressor responses were estimated in humans by measuring blood pressure and arterial plasma norepinephrine during norepinephrine infusion and during yohimbine-induced release of endogenous norepinephrine. Linear pressor response-log norepinephrine concentration relationships were observed during the infusions. At a pressor response of 20 mm...

The effect of neuronal uptake inhibition on basal interstitial release of norepinephrine in the canine heart was examined by use of the multiple tracer dilution-bulk balance technique. A kinetic model incorporating the effects of flow, capillary permeability-surface product for norepinephrine, the interstitial uptake rate constant for neurotransmitter, and plasma norepinephrine input and output...