OBJECTIVETo investigate the effects of ulinastatin on lung injury in hemorrhagic shock rats.

METHODSTwenty-four normal SD rats were randomly divided into 3 groups (n=8), namely the control group, hemorrhagic shock group (group H) and ulinastatin group (group U). In group H and group U, blood was drawn from the femoral artery over a period of 10 min until a mean arterial pressure of 40 mmHg was obtained. Controlled hypotension was then maintained at 40-/+5 mmHg for 60 min by blood drawing or infusion when necessary. All the blood drawn and an equivalent volume of Ringer lactate solution were subsequently infused for resuscitation. Four hours after the resuscitation, the activity of superoxidedismutase (SOD), content of malondialdehyde (MDA), expression of heme oxygenase-1 (HO-1), wet to dry weight ratio (W/D), and pathologic changes of the lung tissues were measured or observed.

RESULTSCompared with those in the control group, the content of MDA, expression of HO-1 and W/D increased significantly in both group H and group U (P<0.05); these indexes in group U were significantly lower than those in group H (P<0.05). The activity of SOD in group U was significantly lower than that in the control group (P<0.05) but higher than that in group H (P<0.05). Optical microscopy demonstrated milder inflammatory cell infiltration and interstitial edema in the lung tissues in group U than in group H.

CONCLUSIONUlinastatin can lower the content of MDA, W/D and the expression of HO-1, increase the activity of SOD, and reduce histological lung injury in rats with hemorrhagic shock.