Plasma concentrations of atrial peptides ANF(1-98) and ANF(99-126) after intravenous infusion: effect of infusate temperature.

Atrial peptides ANF(1-98) and ANF(99-126) were measured in plasma before and after infusion of Ringer-Acetate solution in healthy volunteers. The solution was infused over a 45 min period in an amount equal to 20 per cent of estimated extra-cellular volume. We found that the increase in atrial peptide immunoreactivity after infusion depended on the temperature of the infusate. The molar increase in ANF(1-98) was much larger than the increase in ANF(99-126). We speculate that plasma levels of ANF(1-98) may be a clinically useful parameter of atrial distension secondary to hypervolaemia.