Experimental Study Of Huayulifei On Pulmonary Instersitial Fibrosis In Rats

Objective1.To establish the Bleomycin-induced pulmonary fibrosis model in rats; 2.To observe the effects of Huayulifei on the pulmonary fibrosis in rats;3.To study the effects of Huayulifei on expressions of Smad3 and Smad7 in lung tissue of rats;4.To study the differences of Huayulifei and Hydrocortisone sodium succinate on pulmonary pathology,expressions of TGF-β1 and TNF-α in lung tissue of rats.Methods44 Male Wistar rats were randomly divided into control group,model group,Huayulifei group and hydrocortisone group. The rats were anesthetized with abdominal injection of pentobarbital sodium in a dose of 45mg/kg body weight and then were intratracheally dripped with Bleomycin hydrochloride (5mg/kg in 0.25ml saline) in experimental groups,while 0.9% saline in control group.After being anesthetized with abdominal injection of pentobarbital sodium in a dose of 35mg/kg body weight,the rats were then intratracheally dripped with Bleomycin (5mg/kg) in experimental groups,while 0.9% saline in control group.Treatments were started from the next day with a daily oral Huayulifei ( 13410mg/kg) in Huayulifei group,intraperitoneal Hydrocortisone sodium succinate (25mg/kg) in Hydrocortisone group,and oral saline in control group and model group,respectively.Rats were killed at 14,and 28 days after Bleomycin,lungs isolated for Hematoxylin and eosin-staining,and the expression of Smad3 and Smad7 protein was measured by immunohistochemical technique. Results1.General observation of rats: There were no differences of rats among the four groups in 4 days after Bleomycin. The action,body figure,inspiration and bowels of rats in experimental groups were as well as in control group. The inaction,dyspnea,and out of spirit of rats were found in model group. The rats'manifestations were similar to those in model group at early stage,but the situation turn better after being treat with Hydrocortisone except the loss of weight. The rats'manifestations in Huayulifei group were much better than that of Hydrocortisone group.2.General observation of lung:There were no abnormal findings of the majority rats in control group,whose lung profile was clear,smooth,pink and elastic.Only one rat's lung show red,but no nodule change.The dense bit haemorrhage,focal bleeding,nodule change and lobe volume shrink were found in model group.The findings of lung morphology in Huayulifei group were similar to those in control group.The findings of lung morphology in hydrocortisone group were similar to those in model group.3.Alveolitis and fibrosis:There were completely normal parenchymal structures in control group except one rat.The alveolar septums and pleura were thin,and the alveolar walls were formed in a fine pattern.There were moderate or severe alveolitis manifested by a thickening of alveolar walls accompanied by an accumulation of inflammatory cells within the parenchymal structures in model group at day14.There were moderate or severe fibrosis manifested by a thickening of alveolar walls accompanied by an accumulation of fibroblast,collagen within the parenchymal structures in model group at day28.The inflammatory cells were decreased significantly in hydrocortisone group,but the pulmonary fibrosis was similar to that in model group.The alveolitis and pulmonary fibrosis in Huayulifei group was alleviated significantly compared with those in model group and hydrocortisone group.4.Expressions of Smad3 and Smad7:Smad3 was weakly expressed in cytoplasm and nuclear of inflammatory cells; Smad7 was expressed in cytoplasm of epithelial cells. The continuous expression of Smad3 were significantly increased in model group at day14 and day28(p<0.01).The expression of Smad3 in hydrocortisone group was similliar to that in model group,and was significantly increased than that in Huayulifei group(p<0.01).A significant and progressive decrease in the expression of Smad7 was found in model group.The expression of Smad7 protein in Huayulifei group was significantly higher than that in model group and hydrocortisone group(p<0.01).Conclusions1.Huayulifei can ameliorate bleomycin-induced pulmonary fibrosis and alveolitis in rats;2.Huayulifei may partly work by modulating the expression of Smad3 and Smad7 in lung tissue;3.Hydrocortisone can ameliorate bleomycin-induced alveolitis in rats,but the result of ameliorating pulmonary fibrosis was not obvious.