A comparison of circulating and regional growth hormone-binding protein incirrhosis

The growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis is distur bed in cirrhosis, with elevated basal GH and low IGF-I levels relating to l iver function and prognosis. In plasma, GH is bound to a high-affinity GH-b incling protein (GHBP), which has been found to be slightly reduced in cirr hosis, but with huge variations. GHBP is identical to the extracellular par t of the hepatic GH receptor, but other tissues may contribute to the circu lating GHBP levels. The aim was therefore to measure circulating and region al concentrations of GHBP in relationship to hepatic function and body comp osition in patients with cirrhosis (n = 38) and controls with normal liver function (n = 29). Blood samples from the hepatic, renal, and femoral veins and the femoral artery were collected simultaneously during a hemodynamic investigation. Plasma GHBP was directly measured by a specific and sensitiv e fluoroimmunoassay. Circulating GHBP levels were identical in the patients and controls (mean +/- SD) 1.03 +/- 0.56 nmol/L and 1.02. +/- 0.55 nmol/L, respectively (not significant). We found no significant hepatic, renal, or peripheral arteriovenous extractions or generations of GHBP, and it did no t significantly correlate to liver function. In the controls, GHBP correlat ed significantly with body mass index (SMI) (r=.60, P < .005), whereas this relationship was not found in the patients with cirrhosis. In conclusion, high-affinity GHBP appears to be normal in patients with cirrhosis, with no significant hepatic generation or renal extraction and no association with the severity of the liver disease. Thus, our study supports the hypothesis that tissues other than the liver, despite its abundant GH receptors, may contribute to the circulating GHBP. Copyright (C) 2001 by W.B. saunders Com pany.