Abstract: Objective To evaluate the effect of sodium tanshinone IIA sulfonate (STS) in preventing postoperative peritoneal
adhesions in rats and explore the mechanisms. Methods Sixty SD rats were randomized into 4 equal groups, including a blank
control group, adhesion model group, and high-, moderate-, and low-dose STS-treated groups, and were subjected to injuries
of the parietal peritoneum and cecum to induce peritoneal adhesions, followed by intraperitoneal administration of saline and
STS at the doses of 20, 10, and 5 mg/kg for 7 consecutive days, respectively. Another 15 untreated rats served as the blank
control group. The adhesion scores in each group were recorded after the treatments; the activity of tissue-type plasminogen
activator (tPA) in peritoneal lavage fluid was measured, tPA/PAI-1 protein ratio in the peritoneal tissue was determined by
ELISA, and the expressions of TGF-β1 and collagen I were detected by immunohistochemistry. The anastomotic healing model
was used to assess the impact of STS on wound healing. Results Intraperitoneal administration of STS effectively prevented
peritoneal adhesion without affecting anastomotic healing in the rats. Compared with the adhesion model group, the
STS-treated groups showed increased peritoneal lavage fluid tPA activity and tPA/PAI-1 ratio in the ischemic tissues with
lowered TGF-β1 and collagen I expressions in the ischemic tissues. Conclusion Intraperitoneal administration of STS can
prevent peritoneal adhesion and enhance local fibrinolysis in rats, and these effects may be mediated by TGF-β signaling
pathway.