Effects of recombinant human growth hormone(rhGH) on lung injury mediated by the inflammatory mediators associated with gut ischemia-reperfusion injury in rats

Objective To investigate the effects of recombinant human growth hormone(rhGH) on lung injury mediated by the inflammatory mediators associtated with gut ischemia-reperfusion injury in rats.Methods Forty-two Wister rats were randomly allocated to GIR group and treatment group.Each group was redivided into three subgroups(n = 6) according to varying time points:30 min before ischemia,48 h and 72 h after reperfusion.The treatment group was received abdominal wall subcutaneous injection using rhGH 1 U/kg at the time points of 3 h and 12 h after reperfusion,respectively.The treatment was repeated every 12 hours.The rat model of GIR was established by clamping the superior mesenteric artery for one hour.At different time points,plasma levels of LPS and TNF-α,activities of myeloperoxidase(MPO),neutrophil elastase(NE) and phospholipase A2(PLA2),the W/D weight ratio in the lung tissues were determined.Results The mode of GIR was successfully established.Compared with GIR group,the plasma levels of LPS and TNF-α of the administration of rhGH in the 3rd and 12th hour after GIR were significantly decreased(P 0.01,P 0.05),so was the activity of PLA2 in the lung tissues after 48h post of reperfusion(P 0.05,P 0.01).Compared with GIR group,the W/D weight ratio of the administration of rhGH in the 3rd after GIR was significantly decreased in the lung tissues(P 0.05).Conclusions RhGH could alleviate lung injury induced by GIR in rats,which may be attributed to the reduction of the plasma levels of LPS and TNF-α,and the inhibition of the PLA2 activity in the lung tissues.