Adrenomedullin in cirrhotic and non-cirrhotic portal hypertension.

Abstract

Adrenomedullin (ADM) is a potent vasodilator peptide. ADM and nitric oxide (NO) are produced in vascular endothelial cells. Increased ADM level has been linked to hyperdynamic circulation and arterial vasodilatation in cirrhotic portal hypertension (CPH). The role of ADM in non-cirrhotic portal hypertension (NCPH) is unknown. plasma ADM levels were studied in patients with NCPH, compensated and decompensated cirrhosis in order to determine its contribution to portal hypertension (PH) in these groups. There were 4 groups of subjects. Group 1 consisted of 27 patients (F/M: 12/15) with NCPH due to portal and/or splenic vein thrombosis (mean age: 41+/-12 years), group 2 consisted of 14 patients (F/M: 6/8) with compensated (Child-Pugh A) cirrhosis (mean age: 46+/-4), group 3 consisted of 16 patients (F/M: 6/10) with decompensated (Child-Pugh C) cirrhosis (mean age: 47+/-12). Fourteen healthy subjects (F/M: 6/8) (mean age: 44+/-8) were used as controls in Group 4. ADM level was measured by ELISA. NO was determined as nitrite/nitrate level by chemoluminescence. ADM level in Group 1 (236+/-61.4 pg/mL) was significantly higher than that in group 2 (108.4+/-28.3 pg/mL) and group 4 (84.1+/-31.5 pg/mL) (both P<0.0001) but was lower than that in Group 3 (324+/-93.7 pg/mL) (P=0.002). NO level in group 1 (27+/-1.4 micromol/L) was significantly higher than that in group 2 (19.8+/-2.8 micromol/L) and group 4 (16.9+/-1.6 micromol/L) but was lower than that in Group 3 (39+/-3.6 micromol/L) (for all three P<0.0001). A strong correlation was observed between ADM and NO levels (r=0.827, P<0.0001). Adrenomedullin and NO levels were high in both non-cirrhotic and cirrhotic portal hypertension and were closely correlated, Adrenomedullin and NO levels increased proportionally with the severity of cirrhosis, and were significantly higher than those in patients with NCPH. Portal hypertension plays an important role in the increase of ADM and NO. Parenchymal damage in cirrhosis may contribute to the increase in these parameters.