The preventative role of growth hormone on acute liver injury induced by cardiopulmonary bypass in a rat model.

OBJECTIVE

Cardiopulmonary bypass (CPB)-induced acute liver injury is a life-threatening complication after cardiac surgery and is thought to be associated with inflammatory response and acute-phase response (APR). Recombinant human growth hormone (rhGH) can modulate the APR and inflammatory response. Here, we tested the protective effect of GH on CPB-induced liver injury in the rat.

METHODS

Adult male Sprague-Dawley rats (group G, received 2.5 mg/kg of rhGH intramuscularly at 8a.m. every 24h for 3 days and just before the initiation of CPB; group C served as control) underwent CPB (120 min, 120 ml/kg per minute, 34 degrees C) and were killed 3h after the termination of CPB.

RESULTS

Administration of rhGH markedly increased serum insulin-like growth factor (IGF)-I and IGF-I-binding protein (IGFBP)-3 compared with group C. Group G showed significantly lower serum concentrations of alanine aminotransferase and total bilirubin after CPB termination. Those receiving rhGH demonstrated a significant increase in serum prealbumin and serum transferrin and a marked decrease in serum amyloid A and serum C-reactive protein compared with group C. rhGH significantly decreased serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), whereas no changes were found for serum IL-6 and IL-10 compared with group C. rhGH significantly increased total liver protein content, hepatocyte proliferation, and decreased hepatocyte apoptosis versus group C.

CONCLUSIONS

These results suggest that GH administration in rats seems to play a preventative role in acute liver injury associated with CPB via the decrease in acute-phase proteins, proinflammatory cytokines TNF-alpha and IL-1beta, and hepatocyte apoptosis, which is associated with increase in constitutive hepatic proteins, total liver protein content, and hepatocyte proliferation.