Hemodynamic features of advanced cirrhosis due to chronic bile duct ligation.

AIM

The aim of the present study was to compare the hemodynamic features of portal hypertension in rats with early cirrhosis with those of rats with advanced cirrhosis following common bile duct ligation (CBDL).

METHODS

A total of 53 male Sprague-Dawley rats were used. Hemodynamics were evaluated under conscious and unrestrained conditions 4 weeks and 8 weeks after CBDL, and 4 weeks after a sham operation. Arterial pressure and portal pressure were measured directly via catheters placed in the right femoral artery and main portal vein, respectively. The cardiac index and organ (splanchninc organs, brain, kidneys and lungs) blood flow were determined by the reference sample method using (141)Ce-labeled microspheres (15 mum in diameter). Arterial levels of endothelin-1 and nitrate/nitrite, as well as liver function variables, were also determined.

RESULTS

Portal pressure was significantly higher 8 weeks after CBDL (15.8+/-2.1, n=8) than 4 weeks after CBDL (13.9+/-2.1 mmHg, n=12, p<0.05), and the hyperdynamic circulation of the early period was attenuated (p<0.05). Although hepatic artery blood flow 4 and 8 weeks after CBDL was higher than that after sham operation (p<0.05), portal territory blood flow was not increased. There was a significant positive correlation between portal pressure and portal territory blood flow 8 weeks after CBDL (r=0.822, n=8, p=0.012). In rats with anemia 4 weeks after CBDL, the hemoglobin concentration was negatively correlated with portal territory blood flow (r=-0.597, n=12, p=0.040).

CONCLUSION

Portal pressure was higher 8 weeks after CBDL than 4 weeks after CBDL and increased with portal territory blood flow, suggesting that portal hypertension is maintained by a mechanism consistent with the forward flow theory. Anemia might exacerbate the hyperdynamic systemic circulation 4 weeks after CBDL.