[The low molecular weight heparin on rat pulmonary surfactant associated protein A of acute pulmonary embolism].
OBJECTIVE
To explore the effect of low molecular weight heparin (LMWH) on the changes of pulmonary surfactant associated protein A (SPA) of rats in acute pulmonary embolism.


METHODS
Male SD rats were injected with medical gelfoam microspheres via jugular vein to induce PE model. Rats were randomized into three groups: control group (n = 8), embolism for 2 weeks group (n = 8) and LMWH therapy group (n = 8); The LMWH therapy group were injected Nadroparin subcutaneously immediately after operation, 0.1 ml/10 kg, once every 12 h. Saline were injected into the control group instead of gelfoam granule solution without further procedure. All the rats were sacrificed at the time of 2 weeks. Pulmonary artery pressure were detected by right heart catheterization and artery blood gas were analyzed at the time of sacrifice. Lung tissue were sliced and dyed with HE to observe the embolism of pulmonary artery. Methods of RT-PCR and western blot were used to study the changes of SPA mRNA and SPA protein in lung tissue.


RESULTS
In control group, embolism group and LMWH group, the pulmonary pressure were (14.2 +/- 4.1) mm Hg, (29.0 +/- 8.2) mm Hg, (25.50 +/- 2.74) mm Hg respectively (F3.01, P < 0.05); the artery oxygen blood pressure (PaO2) were (94.1 +/- 8.8) mm Hg, (73.4 +/- 14.3) mm Hg, (82.86 +/- 3.73) mm Hg respectively (F 1.31, P < 0.05); SPA mRNA in three groups were 1.43 +/- 0.51, 0.87 +/- 0.35, 1.07 +/- 0.20 respectively (F 2.87, P < 0.05); and SPA protein were 1.00 +/- 0.00, 0.52 +/- 0.32, 0.90 +/- 0.22 respectively (F 2.96, P < 0.05); Under microscope, lung tissue were seen congestion, edema, infiltration of inflammatory cells in embolism group, which were lessened in LMWH group.


CONCLUSIONS
The lung SPA decrease significantly in acute pulmonary embolism, and LMWH can increase the SPA, which may be one of mechanisms of LMWH in treatment of pulmonary embolism.
Liu
Chun-Ping
CP
Respiratory Department, Peking Union Medical Hospital, Beijing 100730, China.
Lu
Wei-Xuan
WX
Liu
Wei-Guo
WG
Chen
Hang-Wei
HW
Wang
Chen
C
D000208:Acute Disease; D000818:Animals; D000925:Anticoagulants / Q000627:therapeutic use; D015153:Blotting, Western; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D011655:Pulmonary Embolism / Q000188:drug therapy* / Q000473:pathology; D037662:Pulmonary Surfactant-Associated Protein A / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction
D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight; D037662:Pulmonary Surfactant-Associated Protein A; D012333:RNA, Messenger