scholarly journals The significance of determination of heart natriuretic peptides in heart insufficiency

2003 ◽  
Vol 22 (4) ◽  
pp. 311-317
Author(s):  
Marijana Dajak ◽  
Svetlana Ignjatovic ◽  
Nada Majkic-Singh

Heart natriuretic peptides, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) act as key regulators of homeostasis of body fluids volume and blood pressure, by decreasing salt excess and water retention, and by inhibiting intensive action of sympathetic nervous system and secretion of vasoconstrictor hormones. Plasma ANP, N-terminal pro-atrial natriuretic peptide (NT-proANP), BNP and N-terminal pro-brain natriuretic peptide (NT-proBNP) concentrations are considerably increased in heart insufficiency. Intracardiac pressure and atrial and ventricular wall tension are the prime regulators of natriuretic peptides release from the heart. ANP primarily reflects atrial, and BNP ventricular overload. The in vitro stabilities of NT-proANP, BNP and NT-proBNP in EDTA whole blood are sufficient for routine determination. Specific immunochemical tests with acceptable precision are commercially available. However, the determinations are not standardized, which makes difficulties during the comparation of results gained by tests from different manufactures. BNP and NT-proBNP are in relation to ANP and NT-proANP, better diagnostic and prognostic markers of heart insufficiency. BNP measurement is useful for screening in high-risk population. BNP has an excellent negative predictive value for left ventricular dysfunction. It is also suitable for screening hypertensive patients for the discovery of hypertrophy or/and dysfunction of left ventriculy, as well as for risk assessment during the subacute phase of acute myocardial infarction. BNP and NT-proBNP measurement is also useful for treatment guidance and optimization of therapy in heart insufficiency. However, BNP determination cannot replace echocardiography or similar techniques, because these methods provide different information. Thus for the cardiologists natriuretic peptides determination is useful addition to the standard clinical investigation of patients with ventricular dysfunction.

1998 ◽  
Vol 95 (5) ◽  
pp. 547-555 ◽  
Author(s):  
J. G. LAINCHBURY ◽  
M. G. NICHOLLS ◽  
E. A. ESPINER ◽  
H. IKRAM ◽  
T. G. YANDLE ◽  
...  

1.The cardiac natriuretic peptides, atrial natriuretic peptide and brain natriuretic peptide, are degraded via clearance receptors and the enzyme neutral endopeptidase (EC 3.4.24.11). We studied the regional plasma concentrations of these peptides and their response to acute neutral endopeptidase inhibition in a consecutive series of patients with a broad spectrum of severity of cardiac dysfunction who were undergoing diagnostic right and left heart catheterization (24 patients, mean age 62.6 years). 2.Baseline blood samples were obtained for hormone analysis from femoral artery, femoral vein, renal vein, hepatic vein, superior vena cava, coronary sinus and pulmonary artery, and initial haemodynamic measurements were made. Twelve patients then received a neutral endopeptidase inhibitor (SCH 32615, 200 ;mg intravenously) and 12 received vehicle alone. The cardiac catheterization procedure was then completed and haemodynamic and hormone measurements were repeated. 3.Haemodynamic status was similar at baseline in both groups, and at repeated measurement (post-procedure after placebo or active drugs) haemodynamic variables were not significantly different from baseline values. Plasma levels of atrial and brain natriuretic peptides exhibited an arteriovenous increment (344% and 124% respectively) across the heart (femoral artery to coronary sinus) and decrement (by 28–54% and 9–16% respectively) across all other tissue beds (P< 0.05 for all) except the lung (no change). Final levels of atrial natriuretic peptide rose above initial levels at all sites in both groups (P< 0.05) except coronary sinus levels in the vehicle group (no change). The increase was consistently greater in the inhibitor group at all sites (P< 0.05 versus placebo). Levels of brain natriuretic peptide rose at all sites in the inhibitor group only (P< 0.05). The transcardiac step-up in atrial natriuretic peptide was markedly augmented after the administration of neutral endopeptidase inhibitor. Other tissue gradients were not significantly altered by neutral endopeptidase inhibitor. 4.Atrial and brain natriuretic peptides in plasma are degraded by a number of tissues, and respond differently to cardiac catheterization. Neutral endopeptidase has a significant role in determining plasma levels of natriuretic peptides, in part perhaps by influencing the amount of intact peptide reaching the circulation after secretion from the heart.


1993 ◽  
Vol 129 (1) ◽  
pp. 59-64 ◽  
Author(s):  
Eduardo N Cozza ◽  
Mark F Foecking ◽  
Maria del Carmen Vila ◽  
Celso E Gomez-Sanchez

Atrial and brain natriuretic peptides specifically bind to primary cultures of calf adrenal glomerulosa cells. Binding of both natriuretic peptides to the same receptor has been proved by: a Dixon plot showing competitive effects for the binding of 125I-labeled brain natriuretic peptide in the presence of increasing concentrations of unlabeled atrial natriuretic peptide; a Scatchard plot showing a lower dissociation constant (Kd) for atrial natriuretic peptide than for brain natriuretic peptide binding, but the maximum binding (Bmax) values were the same; autoradiography of sodium dodecyl sulfate polyacrylamide gels after cross-linking of 125I-labeled atrial natriuretic peptide and 125I-labeled brain natriuretic peptide, showing the same molecular weights for both peptide receptors—a single 66-kD band in whole cells and a main band at 125 kD in membranes. C-Type atrial natriuretic peptide only slightly displaced atrial natriuretic peptide binding. Angiotensin II- and potassium-mediated stimulation of aldosterone production were inhibited strongly and to the same degree by atrial and brain natriuretic peptide but only slightly by C-type atrial natriuretic peptide. Stimulation of aldosterone production mediated by adrenocorticotropin was only partially inhibited by atrial and brain natriuretic peptide, while baseline aldosterone was not affected. These results suggest that atrial and brain natriuretic peptide bind to the same receptors and provoke the same effects on aldosterone production. The weak effects found with C-type atrial natriuretic peptide suggest that the primary culture of calf adrenal glomerulosa cells contain the guanylate cyclase A receptor.


2003 ◽  
Vol 104 (3) ◽  
pp. 303-312 ◽  
Author(s):  
Hans BENTZEN ◽  
Robert S. PEDERSEN ◽  
Henrik B. PEDERSEN ◽  
Ole NYVAD ◽  
Erling B. PEDERSEN

The purpose of this study was to clarify whether the secretions of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are pulsatile in patients with chronic heart failure (CHF), and whether the rhythmic oscillations for ANP and BNP are abnormal in patients with CHF. Several reports have shown that ANP and especially BNP are valuable indicators of the prognosis in CHF. Previously, a pulsatile secretion has been described for ANP and BNP in healthy humans and for ANP in CHF patients. More information about the secretion pattern of BNP in heart failure is necessary to increase the clinical usefulness of BNP in patients with CHF. Patients with left ventricular systolic dysfunction and CHF (n = 12) and controls (n = 12) were investigated. Plasma ANP and BNP levels were determined every 2min during a 2-h period by radioimmunoassay and analysed for pulsatile behaviour by Fourier transformation. All patients and controls had significant rhythmic oscillations in plasma ANP levels, and 11 patients with CHF and 10 controls had significant rhythmic oscillations in plasma BNP levels. The amplitude of the main frequency was considerably higher in patients with CHF than in controls (ANP: CHF, 4.76pmol/l; controls, 0.75pmol/l; P<0.01. BNP: CHF, 3.24pmol/l; controls, 0.23pmol/l; P<0.001; all values are medians), but the main frequency did not differ significantly between the group with CHF and the control group for either ANP or BNP. Patients with CHF demonstrate pulsatile secretion of ANP and BNP with a much higher absolute amplitude, but with the same main frequency as healthy subjects.


1993 ◽  
Vol 291 (1) ◽  
pp. 83-88 ◽  
Author(s):  
A J Kenny ◽  
A Bourne ◽  
J Ingram

Endopeptidase-24.11 (E-24.11, EC 3.4.24.11) is widely believed to play a physiological role in metabolizing atrial natriuretic peptide (ANP). Since the discovery of ANP, new natriuretic peptides have been isolated and other peptides synthesized as receptor ligands. The hydrolysis in vitro of six related peptides by the endopeptidase has been studied, mainly by h.p.l.c. The initial attack on the 32-residue form of pig brain natriuretic peptide (pBNP-32) was shown to be at the Ser20-Leu21 bond, as had been previously shown for the 26-residue form. In contrast, human brain natriuretic peptide-32 (hBNP-32), which differs in ten residues from pBNP-32, was attacked first at the Met4-Val5 bond, releasing the N-terminal tetrapeptide, and only later at bonds within the ring: at Arg17-Ile18 and subsequently at four other sites. Urodilatin, which has a four-residue extension at the N-terminus compared with alpha-human atrial natriuretic peptide-28 (alpha-hANP), was degraded at about half the rate of the latter, though the C-terminal Phe-Arg-Tyr was released at the same rate. The 22-residue C-type natriuretic peptide was hydrolysed more rapidly than alpha-hANP, as were two C-receptor ligands (peptides with deletions within the ring): C-ANP4-23 (rANP4-23 des-Gln18,Ser19,Gly20,Leu21,Gly22) and SC 46542 (hANP5-28 des-Phe8,Gly9,Ala17,Gln18). Angiotensin-converting enzyme failed to hydrolyse pBNP-32, hBNP-32 or 125I-rat (r) ANP, even after prolonged incubation. Km and kcat values were determined for the hydrolysis of alpha-hANP, porcine BNP-26, porcine BNP-32 and 125I-rANP by E-24.11. Ki values were determined for six peptides, alpha-hANP, urodilatin, hBNP-32, C-type natriuretic peptide (CNP), SC 46542 and C-type natriuretic peptide (C-ANP4-23), in radiometric assays of E-24.11 with either [125I] insulin B chain or [125I] rANP as substrate. The Ki values (2.5-13 microM) for CNP were the lowest of any of the group, whereas those for hBNP-32 (151-172 microM) were the highest. The physiological significance of these results is discussed, especially in regard to the relative resistance of hBNP-32 to attack and the ability of the C-receptor ligands to compete with natriuretic peptides for hydrolysis by E-24.11.


The Lancet ◽  
1993 ◽  
Vol 341 (8853) ◽  
pp. 1105-1109 ◽  
Author(s):  
A. Lerman ◽  
R.J. Gibbons ◽  
R.J. Rodeheffer ◽  
K.R. Bailey ◽  
L.J. McKinley ◽  
...  

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