[The expression and function of pulmonary surfactant protein A in severe acute pancreatitis in rats].
OBJECTIVE
To investigate the expression and function of surfactant protein A (SP-A) in lung in rats with acute lung injury (ALI) induced by severe acute pancreatitis (SAP).


METHODS
Twenty Sprague-Dawley (SD) rats were randomly divided into 2 groups: sham operation group (sham, n=10) and SAP model group (SAP, n=10). SAP model was reproduced in SAP group. In sham group laparotomy only was done. Serum amylase (AMY) levels, partial pressure of oxygen in artery (PaO2) and lung wet/dry (W/D) ratio were determined. SP-A mRNA expression in lung was detected by reverse transcription-polymerase chain reaction (RT-PCR). SP-A protein expression in lung tissues was assessed by immunohistochemistry. The pathologic changes in pancreas and lung were observed 24 hours after reproduction of the model.


RESULTS
Compared with sham group, PaO(2) in SAP group was decreased significantly [(96.78+/-3.81) mm Hg vs. (79.24+/-5.84) mm Hg, 1 mm Hg=0.133 kPa, P<0.05]. Serum levels of AMY and W/D ratio in SAP group were remarkably higher than that in sham group [(1 193.41+/-192.54) U/L vs. (7 144.19+/-727.91) U/L, 3.70+/-0.90 vs. 8.57+/-2.45, both P<0.05]. The expression of SP-A mRNA in lung tissues in SAP group was significantly down-regulated compared with that in sham group (1.21+/-0.10 vs. 0.80+/-0.11, P<0.05). The expression of SP-A protein in lung in SAP group was significantly decreased than that in sham group (7 982.22+/-3 689.57 vs. 3 497.99+/-2 958.21, P<0.05). The pathologic changes in pancreas and lung were marked in SAP group. The expression of SP-A protein and mRNA showed significant negative correlation with the extent of lung injury (r1= -0.876, P<0.01; r2= -0.713, P<0.05).


CONCLUSIONS
SP-A decreases remarkably in ALI induced by SAP. Type II alveolar epithelial cells might play an important role in ALI induced by SAP.
Zhang
Xue-mei
XM
Department of General Surgery, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, Liaoning, China. zhangxuemeidl@163.com
Chen
Hai-long
HL
Wang
Zhao-hui
ZH
D000208:Acute Disease; D055371:Acute Lung Injury / Q000378:metabolism* / Q000503:physiopathology; D000818:Animals; D004195:Disease Models, Animal; D008297:Male; D010195:Pancreatitis / Q000378:metabolism*; D037662:Pulmonary Surfactant-Associated Protein A / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D037662:Pulmonary Surfactant-Associated Protein A