Effect of dexamethazone on hepatic vascular response in experimental sepsis

The aim of the present study was to evaluate the effect of dexamethasone-pretreatment on the hepatic artery and portal vein of septic rats, which were generated by lipopolisaccarides (LPS) intraperitoneal injection.

Thirty-six albino Wistar rats were used and constructed as LPS (n = 12), control (n = 12), dexamethazone-pretreatment (n = 6) and dexamethazone-control (n = 6) groups. Hepatic artery and portal vein rings were excised and placed in Krebs-Henseleit solution. Vessel rings were contracted with phenylephrine adding to the organ chamber in cumulative doses. Then the contraction-response curves were drawn.

In the LPS group, phenylephrine evoked contractions were reduced in both hepatic artery and portal vein rings in comparison to the control group. In the dexamethasone-control group, phenylephrine-evoked contractions were increased but not significantly. Dexamethasone-pretreatment increased the phenylephrine-evoked contractions close to the values of control group for both types of rings.

Dexamethasone pretreatment corrected the vascular hyporeactivity to phenyleprine in isolated portal vein and hepatic artery rings prepared from the LPS treated rats in experimental sepsis. This might have occurred as a result of inhibition of inducible nitric oxide synthase expression.