Int J Med Sci 2019; 16(4):593-601. doi:10.7150/ijms.32632 This issue

Research Paper

Suppressive Effects of Aspirin for Postthoracotomy Pleural Adhesion in Rats

Shunta Ishihara1, Kazuhiro Ito1✉, Satoru Okada1, Masanori Shimomura1, Junichi Shimada1, Tadanori Yamaguchi2, Masayoshi Inoue1

1. Division of Thoracic Surgery, Department of Surgery, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8566, Japan
2. Department of Cytopathology, Ayabe City Hospital, 20-1 Aono-cho Ootuka, Ayabe 623-0011, Japan

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Ishihara S, Ito K, Okada S, Shimomura M, Shimada J, Yamaguchi T, Inoue M. Suppressive Effects of Aspirin for Postthoracotomy Pleural Adhesion in Rats. Int J Med Sci 2019; 16(4):593-601. doi:10.7150/ijms.32632. Available from

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Background: Postoperative adhesion is one of major concerns at re-thoracotomy. Aspirin has both the anti-platelet and anti-inflammatory effects, and decreases several cytokines production.

Objective: We investigated that aspirin could reduce postoperative adhesion formation in a rat model.

Methods: We cauterised the lung visceral pleural to make postoperative adhesion in rats. The animals were allocated to a control group and an aspirin administration group (100 mg/kg/day for 14 days). We performed re-thoracotomy and evaluated the adhesion lengths on day 14. We also investigated the cytokine expression in the adhesion region and the peripheral tissue with platelet-derived growth factor (PDGF), platelet-derived growth factor receptor (PDGFR), alpha smooth muscle actin (α-SMA), transforming growth factor beta 1 (TGF-β1), and vascular endothelial growth factor-A (VEGF-A), sequentially.

Results: The adhesion lengths were significantly shorter in the aspirin group than that in the control group (8.7±2.0 mm vs 11.2±1.1 mm, p=0.024). The expressions of PDGF and PDGFR were lower in the aspirin group than that in the control group on day 3. The expression of α-SMA on fibroblasts decreased in the aspirin group on day 3. There was no significant difference in the expressions of TGF-β1 and VEGF-A with administration of aspirin.

Conclusions: Aspirin could reduce postoperative pleural adhesion by inhibiting the expression of PDGF.

Keywords: pleural adhesion, reoperation, aspirin, platelet, platelet-derived growth factor