Plasma levels of brain natriuretic peptide in healthy subjects and patients with essential hypertension: response to posture.
1. To examine whether posture-induced changes in central volume affect brain natriuretic peptide secretion, plasma levels of human brain natriuretic peptide-32-like immunoreactivity (hBNP-32-li) were measured by radioimmunoassay in 11 healthy subjects and 20 patients with essential hypertension after 15 min supine, 15 min sitting and 15 min with the legs raised at 60 degrees, together with plasma atrial natriuretic peptide concentration, plasma renin activity and plasma aldosterone concentration. 2. In the supine position, the plasma hBNP-32-li level was 1.57 +/- 0.10 fmol/ml in healthy subjects and significantly higher in hypertensive patients (2.39 +/- 0.13 fmol/ml, P < 0.001). In both groups, plasma hBNP-32-li level significantly (P < 0.001) decreased when sitting (normotensive, 1.22 +/- 0.08 fmol/ml; hypertensive, 1.85 +/- 0.15 fmol/ml, P < 0.001 versus normotensive) and increased again after leg raising (normotensive, 2.13 +/- 0.12 fmol/ml; P < 0.002 versus resting; hypertensive, 2.84 +/- 0.16 fmol/min, P < 0.001 versus resting, P < 0.025 versus normotensive). 3. The plasma atrial natriuretic peptide concentration showed similar behaviour to the plasma hBNP-32-li, whereas plasma renin activity and plasma aldosterone concentration increased during sitting and decreased during leg raising in both healthy subjects and hypertensive patients, who had significantly higher plasma aldosterone levels when supine and sitting.(ABSTRACT TRUNCATED AT 250 WORDS)
La Villa
G
G
Cardiovascular Unit, Clinica Medica II, University of Florence School of Medicine, Italy.
Vena
S
S
Conti
A
A
Fronzaroli
C
C
Brat
A
A
Lazzeri
C
C
Tosti Guerra
C
C
Madiai
S
S
Marra
N
N
Franchi
F
F
D000328:Adult; D000450:Aldosterone / Q000097:blood; D009320:Atrial Natriuretic Factor / Q000097:blood; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000097:blood*; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain; D009419:Nerve Tissue Proteins / Q000097:blood*; D011187:Posture / Q000502:physiology*; D012083:Renin / Q000097:blood
D009419:Nerve Tissue Proteins; D020097:Natriuretic Peptide, Brain; C076910:brain natriuretic peptide, porcine; D000450:Aldosterone; D009320:Atrial Natriuretic Factor; D012083:Renin