Increased Release of the N-Terminal and C-Terminal Portions of the Atrial Natriuretic Factor Prohormone during Immersion-Induced Central Hypervolemia in Cirrhotic Humans

Abstract

The role of peptides from the N-terminus and C-terminus of the 126 amino acid (a.a.) atrial natriuretic factors (ANF) prohormone in modulating renal sodium and water handling in cirrhotic patients has not been defined. Eight cirrhotic individuals were evaluated; their mean basal circulating concentration of the C-terminus (a.a. 99–126; i.e., ANF) was 25 ± 2 fmol/ml, not different from the 22 ± 1 fmol/ml value found in 54 normal volunteers. On the other hand, the basal circulating concentrations of the whole N-terminus (a.a. 1–98) and the midportion of the N-terminus (namely a.a. 31–67; pro ANF 31–67) of the ANF prohormone in these cirrhotic subjects of 704 ± 52 and 654 ± 83 fmol/ml were significantly elevated (p < 0.05; ANOVA) in comparison to control values (531 ± 25, 317 ± 22 fmol/ml, respectively). Following equilibration on a 10 mmol/day sodium diet, the responsiveness of the N-terminus and C-terminus of ANF prohormone to 3 h of water immersion, which induces marked acute central volume expansion, was evaluated in these 8 seated cirrhotic patients. There was a prompt increase in the circulating concentrations of immunoreactive (ir) pro ANF 1–98 (whole N-terminus), ir pro ANF 31–67, and ir ANF (C-terminus) within 15 min of immersion (p < 0.05; ANOVA) compared to their preimmersion values. The response of circulating ir pro ANF 1–98, pro ANF 31–67, and ANF concentrations in these 8 cirrhotic subjects to immersion was significantly greater (p < 0.05; ANOVA) than that of 7 healthy volunteers undergoing an identical 3-hour immersion study. With cessation of immersion, the C-terminus decreased within 30 min to a concentration not significantly different from preimmersion values, whereas the N-terminus and pro ANF 31–67 remained significantly elevated after 1 h.

Fluid balance in patients with chronic renal failure assessed with N‐terminal proatrial natriuretic peptide, atrial natriuretic peptide and ultrasonography

“…In a clinical study, Vesely et al . (1991) found a maximal increase in both the N‐terminus and C‐terminus of ANP prohormone in cirrhotic patients in response to central hypervolaemia induced by water immersion.…”

Combined Treatment with Vessel Dilator and Kaliuretic Hormone in Persons with Congestive Heart Failure

“…Exclusion criteria included anyone with a creatinine level above 1.5 mg/dl, because these cardiac hormones increase in the circulation of persons with renal failure (18,19). Also excluded was anyone with cirrhosis and ascites, because these peptide hormones also increase in their circulation in this disease state (20,21). Patients' prescribed medications were not taken the day of the study.…”

Natriuretic Peptide Family: New Aspects

“…Head-out water immersion manoeuvre in humans, which it is able to induce central hypervolemia, has shown that there is a normal release of ANP in this population [78]. Head-out water immersion manoeuvre in humans, which it is able to induce central hypervolemia, has shown that there is a normal release of ANP in this population [78].…”