OBJECTIVETo observe dynamically the expressions of intercellular adhesion molecule-1 (ICAM-1) and P-selectin (Ps) in the vascular endothelium in rats with pulmonary thromboembolism (PTE) and the effect of Safflower Injection (SI).

METHODSRats were randomly divided into the normal group, the model group and the treatment group. PTE model was induced by intravenous injection of auto-blood clots, and SI was injected intravenously immediately after modelling with 2 ml/(kg d) for 5 days to the rats in the treatment group. Animals were sacrificed in batches at the 1st, 3rd, 24th, 72nd and 120th h after embolization to observe the pathological changes and detect the protein and mRNA expressions of ICAM-1 and Ps in pulmonary vascular endothelium by immunohistochemistry and in situ hybridization respectively.

RESULTSPathological observation showed obvious embolism in pulmonary arteries and inflammatory reaction after modelling, which was abated after SI treatment. ICAM-1 and Ps expressions were elevated at the 3rd and the 1st h after embolization respectively (both P < 0.01), which also were abated in the treatment group.

CONCLUSIONSI may alleviate pulmonary injury in PTE rats by down-regulating the expressions of ICAM-1 and Ps.