Plasma atrial natriuretic peptide

Nakamura, T., Suzuki, T., Kawagoe, Y., Koide, H. Polymyxin B-immobilizcd fiber hemoperfusion attenuates increased plasma atrial natriuretic peptide and brain natriuretic Peptide levels in patients with septic shock. ASAIO J 54 (2008) 210-213. 

Plasma atrial natriuretic peptide levels increased in healthy volunteers who ingested 100 g of licorice daily for 8 wk (Forslund et al., 1989). This effect is thought to be a physiologic response to prevent licorice-induced fluid retention and hypertension. 

Forslund T, Fyhrquist F, Froseth B, Tikkanen I. Effects of licorice on plasma atrial natriuretic peptide in healthy volunteers. J Intern Med 1989 225 95-9. 

Oyama, M. A., D. D. Sisson, and P. F. Solter. 2007. Prospective screeiung for occult cardiomyopathy in dogs by measurement of plasma atrial natriuretic peptide, B-type natriuretic peptide, and cardiac troponin-1 concentrations. American Journal of Veterinary Research 68 42-47. 

B8. Beishuizen, A, Gotz, J. M., Kip, L Haanen, C., and Vermes, I Elevated plasma levels of endothelin are associated with the severity of sepsis and presence of shock in contrast to the levels of atrial natriuretic peptide. Med. Inflam. 1,419-423 (1992). 

M30. Mitaka, C., Nagura, T., Sakanishi, N Tsunoda, Y., and Toyooka, H., Plasma a-atrial natriuretic peptide concentrations in acute respiratory failure associated with sepsis Preliminary study. Crit. Care Med. 18, 1201-1203 (1990). 

Atrial natriuretic peptide (ANP) is produced by specialized myocytes in the atria of the heart. Secretion is stimulated by increased filling and stretch of the atria in response to plasma volume expansion. The effects of ANP include vasodilation, diuresis (increased urine production), and increased sodium excretion. Taken together, these effects decrease blood volume and blood pressure toward normal. 

Atrial natriuretic peptide is released from myocardial cells in the atria of the heart in response to an increase in atrial filling, or an increase in plasma volume. This hormone inhibits the release of renin. With less angiotensin Il-induced vasoconstriction of the afferent arteriole, RBF, GFR, and urine output increase. The increased loss of water and solutes decreases blood volume toward normal. 

Sodium reabsorption is also influenced by ANP. The original decrease in plasma volume leads to a decrease in atrial filling and a decrease in the release of ANP from the myocardium. Atrial natriuretic peptide, which acts on vascular smooth muscle, granular cells of the kidney, and the adrenal cortex, normally causes the following ... 

Atrial Natriuretic Peptide Potentiator Diuretics. Neural endopeptidase inhibitors or atrial peptidase inhibitors are compounds that inhibit the enzyme (hat degrades ANP. resulting in higher plasma concemratioas, and longer duration of action, of ANP. The diuretic effects of this class... 

In the example of a-human atrial natriuretic peptide (ANP), found at increased plasma levels in patients with heart failure, Numata et al. [70] demonstrated how IPCR sensitivity accelerated conventional assay procedures. For individual treatment of the cardiac patients, a prompt detection of atrial distension by the presence of the ANP marker would be desirable. Common ANP tests, however, take 2-3 days for the quantification of plasma by radiometric or ELISA techniques. With sandwich IPCR, the assay time could be shortened to 5 hours. A good correlation between IPCR and radiometric detection was maintained, combined with an additional improvement of the detection limit to 2 ng/L ANP. The average level of ANP in plasma for 25 patients with heart failure was found to be 117 100 ng/L, significantly higher than the typical level of 20 14 ng/L for healthy subjects. 

Numata Y, Matsumoto Y. Rapid detection of alpha-human atrial natriuretic peptide in plasma by a sensitive immuno-PCR sandwich assay. Clin Chim Acta 1997 259(1-2) 169-176. 

Zhou XJ, Pandian D, Wang QX, Vaziri ND (1997) Erythropoietin-induced hypertension is not mediated by alterations of plasma endothelin, vasopressin, or atrial natriuretic peptide levels. J Am Soc Nephrol 8 901-905... 

Angeli, P., Caregaro, L., Menon, R, Sacerdoti, D., deToni, R., Merkel, C., Gatta, A. Variability of atrial natriuretic peptide plasma levels in ascitic cirrhotics pathophysiological and clinical implications. Hepatology 1992 16 1389-1394... 

Endopeptidase-24.II (EC 3.4.24.11 NELP neutral endopeptidase neprilysin, enkephalinase) is a zinc-metalloproteinase, found both in soluble and plasma membrane forms. It is an important enzyme in neuropeptide degradation. Notable neuropeptide substrates include tachykinins (substance P, neurokinin A, neurokinin B), endothelins (ET-1, ET-2, ET-3), atrial natriuretic peptide, neurotensin, somatostatin and cholecystokinins. 

Space travel is associated with a decrease in blood and plasma volumes and is further associated with increases in plasma antidiuretic hormone, atrial natriuretic peptide, growth hormone, cortisol, and corticotropin concentrations. In contrast, the plasma renin activity may be decreased by as much as 50%. Plasma aldosterone may also decrease but to a lesser extent. In spite of the stress of space travel the plasma concentrations of catecholamines are usually unaffected. Plasma and urine calcium concentrations increase during... 

Badola F, Benedict C. Rapid, simplified radioimmunoassay of arginine-vasopressin and atrial natriuretic peptide in plasma. Clin Chem 1988 34 970-3. 

The natriuretic peptide family has three members, atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). ANP is stored mainly in the right atrium, whereas BNP is found mainly in the ventricles. Both are released in response to pressure or volume overload. CNP is found mainly in the brain and has very low plasma concentrations. ANP and BNP plasma concentrations are elevated in patients with heart failure and are thought to balance the effects of the RAA system by causing natriuresis, diuresis, vasodilation, decreased aldosterone release, decreased hypertrophy, and inhibition of the SNS and the RAA system. 

In persons with normal kidney function, sodium balance is maintained at a sodium intake of 120 to 150 mEq/day. The fractional excretion of sodium (FENa) is approximately 1% to 3%. Water balance is also maintained, with a normal range of urinary osmolality of 50 to 1200 mOsm/L. In patients with severe CKD (Stages 4 and 5), sodium balance is achieved, but results in a volume-expanded state. FENa may increase to as much as 10% to 20%, possibly due to increased concentrations of atrial natriuretic peptide. An osmotic diuresis occurs with an increase in FENa leading to obligatory water losses and impairment in the kidney s ability to dilute or concentrate urine (urinary osmolality is often fixed at that of plasma or approximately 300 mOsm/L). Nocturia is present relatively early in the course of CKD (Stage 3) secondary to the defect in urinary concentrating ability. Total renal sodium excretion decreases despite an increase in sodium excretion by remaining nephrons. Volume overload with pulmonary edema can result, but the most common manifestation of increased intravascular volume is systemic hypertension. ... 

FM Rosmalen, et al. A sensitive radioimmunoassay of atrial natriuretic peptide in human plasma—Some guidelines for clinical applications. Z. Kardiol. 77 20, 1988. 

D) Patients with heart failure usually have high plasma levels of atrial natriuretic peptide (ANP)... 

Thus, the volume of distribution of the central compartment in which peptides and proteins initially distribute after intravenous administration is typically 3 to 8 L, approximately equal to slightly higher than the plasma volume [19] (approximate body water volumes for a 70-kg person interstitial 12 L, intracellular 27 L, intravascular 3 L) [34]. The total volume of distribution (V ) is frequently 14 to 20 L, not more than twice the initial volume of distribution (Vc) [13, 28]. This distribution pattern has, for example, been described for the somatostatin analog octreotid (Vc 5.2-10.2 L, VIIIa inhibitor eptifibatide (Vc9.2 L) [35-37].Active tissue uptake and binding to intra- and extravascular proteins, however, can substantially increase the volume of distribution of peptide and protein drugs, as, for example, observed with atrial natriuretic peptide (ANP) [38]. 

The earliest endocrine abnormality in almost all types of cardiac disease is increased release of the heart s own hormones, the natriuretic peptides ANP and BNP (A for atrial, B for brain, where it was first discovered), and their concentration in plasma may become a guide to therapy. These peptides normally suppress renin and aldosterone production. 

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