Effects of ulinastatin on ventilator-induced lung injury in rats

Objective To investigate the effect of ulinastatin on the ventilator-induced lung injury in rats. Methods Thirty-six healthy male SD rats, weighting 300~350 g, were randomly divided into 3 groups(n=12 every group), control group(group C); mechanical ventilation group(group V) and ulinastatin group(group U). The animals were anesthetized with intraperitoneal 20% urethane solution 1.4g/kg and tracheostomized. The femoral artery and vein were cannulated for blood sampling and drug administration. The animals were mechanically ventilated for 2.5 h(VT =40 ml/kg, RR 40 bpm, I: E=1:1, FiO2 2l%). group U was given ulinastatin about 10 000 u/100 g intraperitoneally 30 minutes before the experiment start, while in groups V and C,the rats were given equal volume of normal saline nstead of ulinastatin. Aterial blood samples were collected at the end of ventilation. The animals were then sacrificed and the lungs were removed for microscopic examination and determination of the content of TNF-α, IL-8, and W/D lung weight ratio, WBC count,total protein(TP), TNF-α, IL-8, concentrations in broncho-alveolar lavage nuid(BALF). Results Compared with those in group C,the contents of TNF-α, IL-8, 1ung permeability index(LPI), WBC count and W/D ratio in group V were significantly increased(All the P0.05). Compared with those in group V, the contents of TNF-α, IL-8, LPI, WBC count and W/D ratio in group U were significantly decreased(All the P0.05). The pathological damage was attenuated in group U compared with that in group V. Conclusion Ulinastatin can attenuate the ventilator-induced lung injury through inhibition of inflammatory response in rats.