||This group investigated 62 caucasian subjects with essential
hypertension, and measured renin levels on low and high sodium intake for two weeks each.
They also studied the adrenal (aldosterone concentration) and renal haemodynamic (renal
plasma flow) response to an infusion of angiotensin II. After excluding the subjects with
low renin concentrations on a low sodium intake, they divided those with normal and high
renin levels into modulators and non-modulators according to high or low responsiveness to
angiotensin II. They showed that, even though all three groups had similar levels of
systolic, diastolic and pulse pressure, the non-modulator and low renin subjects were
similarly sodium sensitive in terms of blood pressure response to high salt, this being in
both groups around three times that of the modulators.