Atrial natriuretic peptide, angiotensin, norepinephrine and electrolyte in cerebrospinal fluid of essential hypertension

We determined concentrations of atrial natriuretic peptide (ANP), angiotensin (Ang), norepinephrine (NE) and electrolyte in plasma and cerebrospinal fluid (CSF) to study possible roles of these substances within the brain in human hypertension. Blood and CSF samples were obtained from 10 patients with mild to moderate essential hypertension (EHT) aged 40-65 y and 10 age-matched normotensive subjects (NT) on a regular salt diet (8 g/day). Levels of ANP. NE, Na, K, Ca and Cl in CSF and plasma were comparable between EHT and NT. Plasma renin activity, plasma and CSF Ang II were lower in EHT than NT. CSF Ang III tended to be lower in EHT. There was no correlation between CSF and plasma ANP. or between CSF and plasma Ang II. Our results indicate that CSF levels of ANP may not be altered in middle aged patients with mild to moderate hypertension. It is also suggested that Ang II. NE and sodium in the central nervous system may not have important roles in hypertension of those patients.