Effects of High Dose Atrial Natriuretic Peptide on Renal Haemodynamics, Sodium Handling and Hormones in Cirrhotic Patients with and Without Ascites

To elucidate and to try to reverse the antinatriuretic mechanisms in liver cirrhosis, atrial natriuretic peptide (ANP) was given as a pharmacological bolus dose (2 µg per kg body weight) to 14 cirrhotic patients, and as a control to 14 healthy subjects. The nine patients with ascites had baseline values of glomerular filtration rate (GFR), effective renal plasma flow (ERPF) and blood pressure (BP) similar to controls. Their distal tubular fractional reabsorption of sodium (DFRNa), estimated by the lithium clearance technique, was higher than in controls, and so were plasma values of aldosterone (564 vs. 119 pmol 1−1 medians), endothelin (1.23 vs. 0.63 pmol 1−1), ANP (7.5 vs. 3.6 pmol 1−1) and cyclic GMP (8.8 vs. 4.6 nmol 1−1); p<0.01 for all. The five patients without ascites had higher GFR and ERPF, and lower plasma angiotensin II than controls. After ANP injection, similar plasma levels of ANP and cyclic GMP were reached in all groups. Urinary sodium excretion rate increased in controls (0.23 to 0.52 mm...