Isolation and structural analysis of the circulating human cardiodilatin (alpha ANP)

Abstract

A new method was applied to isolate a polypeptide hormone from human blood. The polypeptides from 1,000 1 of hemofiltrate with a molecular weight lower than 20 kDaltons were adsorbed to 2.5 kg alginic acid, then eluted, precipitated, and desalted on a G-25 Sephadex column, thus obtaining a crude lyophilised plasma polypeptide extract. These polypeptides were further submitted to ion-exchange chromatography. Thereafter, two steps of HPLC were carried out to purify a distinct polypeptide which was the circulating form of cardiodilatin (CDD) in this case. The amino acid analysis, C-terminal enzymatic cleavage by carboxypeptidase A, and sequence analysis showed that the only form of circulating cardiodilatin is the 28 amino acid residue containing molecule, cardiodilatin-99-126 cleaved from the C-terminus of cardiodilatin-126 and identical with alpha-ANP (alpha atrial natriuretic polypeptide). Other bioactive molecular forms of the polypeptide hormones of the cardiodilatin family were not detected in the hemofiltrate. The isolation procedure was followed up by a bioassay using in vitro vascular smooth muscle relaxation.

hBD‐1: a novel β‐defensin from human plasma

“…Recently we have improved the large-scale extraction of peptides from human hemofiltrate (HF) earlier described [15]. HF is obtained from patients with end stage renal disease (ESRD) undergoing hemofiltration for the elimination of uremic toxins [16].…”

Urodilatin: a new approach for the treatment of therapy‐resistant acute renal failure after liver transplantation

“…URO was extracted from human urine [4] and belongs to the family of natriuretic-vasorelaxant peptides earlier found in heart atria [5-81. URO exhibits an N-terminal prolongation of four amino acids compared to the circulating cardiac hormone [9] and is probably produced and differentially processed in kidney distal tubular cells [ 101.…”

Effects of Environmental Temperature on Atrial Natriuretic Peptide (ANP) -granules of Auricular Cardiocytes and Plasma ANP Level in Pregnant Rats

“…It is well known that atrial cardiocytes in mammals are endocrine cells which secrete atrial natriuretic peptide (ANP) [1][2][3] which has diuretic, natriuretic and vasodilatory properties and exerts an inhibitory action on aldosterone, cortisol, arginine vasopressin and renin release.…”