Plasma human atrial natriuretic peptide levels in patients with liver cirrhosis.

Plasma levels of human atrial natriuretic peptide (hANP) were investigated in patients with liver cirrhosis, and the relationships between plasma hANP levels and the following factors were studied: presence of ascites, serum and urine electrolytes, plasma renin activity, angiotensin I and II, aldosterone, catecholamines, prostaglandin derivatives, conventional liver function tests and circulating blood volume. Plasma hANP level was significantly (P < 0.05) elevated in patients with ascites (mean = 58.6 pg/mL, s.e.m. = 8.8) compared with cases without ascites (mean = 36.6 pg/mL, s.e.m. = 2.6). With the disappearance of ascites, the level fell to normal in most cases. Urine sodium excretion was positively correlated with plasma hANP in patients without ascites, but not in patients with ascites. The plasma hANP level was disproportionately high for the rate of urinary Na excretion in cirrhotics with ascites. The plasma hANP level was not correlated with any of the other factors such as blood volume, renin-angiotensin-aldosterone levels, catecholamines and liver function tests. These results suggest that plasma hANP levels are elevated in cirrhotic patients especially with ascites, but the natriuretic response of the kidney to this raised hANP level can be impaired in patients with liver cirrhosis and ascites.