Effect of endotoxin on portal hemodynamic in rats

To study the effects of endotoxin on portal hemodynamic of normal and noncirrhotic portal hypertensive rats.

Normal rats were intraperitoneally injected with 0.1, 0.25, 0.5, 1.0, 2.0, 4.0mg.kg(-1) of lipopolysaccharide(LPS) respectively, portal vein ligation(PVL) and intrahepatic portal occlusion (IPO) rats as well as sham-operated rats were treated with an intraperitoneal injection of 1.0mg.kg(-1) of LPS, the portal vein pressure(PVP), portal venous flow(PVF), inferior vena cava pressure(IVCP) and portal vein resistance(PVR) were detected 4 hours after injection.

PVF of the 5 groups of rats accepting intraperitoneal injection of LPS were increased from 14.0 to 18.0, 22.2, 26.2, 34.8, 39.6, 38.8 mL.min(-1) 4 hours after injection of LPS(P<0.01). PVP of the 4 groups of rats accepting more than 0.1mg/kg.b.w of LPS was increased from 1.04 to 1.25, 1.50, 1.80, 1.95, 2.05 kPa(P<0.01). The increments of PVF and PVP were in a dose-dependent manner of LPS. PVR of the 5 groups of rats was decreased from 51 to 42,44,48,45,44,47 kPa.min.L(-1) (P<0.05) and no dose-dependent manner was observed. PVF of PVL, IPO and sham-operated rats increased from 22.6 to 32.8, 22.0 to 28.0, 14.0 to 34.8 mL.min(-1) (P<0.01), and PVP increased from 1.86 to 2.24, 1.74 to 1.95, 1.04 to 1.80 kPa(P<0.01), PVR decreased from 71 to 61, 67 to 61, 52 to 44 kPa.min.L(-1) after intraperitoneal injection of 1mg.kg(-1) of LPS. The increments of PVF and PVP of PVL and IPO rats were significantly less than the sham-operated rats(P<0.01), There was no significant difference between the amounts of PVR decreased in the two groups of PHT model rats and sham-operated rats(P>0.05) after intraperitoneal injection 1mg.kg(-1) of LPS.

Endotoxin could prompt portal hypertension of the normal and noncirrhotic portal hypertensive rats by increasing portal blood flow mainly.