Objective To elucidate the efficacy and possible mechanism of Qingchang mixture in ameliorating postoperative abdominal adhesions in rats.Methods Seventy-five Sprague-Dawley rats were randomly allocated into five experimental groups:the control group,the sham-operated group,the model group,the Qingchang mixture treatment group and the sodium hyaluronate treatment group.Except the control group and the sham-operated group,the other three groups were treated with cecal abrasion method to establish the rat model of abdominal adhesion.In the sodium hyaluronate group,2 mL sodium hyaluronate gel was meticulously applied to the injured abdominal wall and cecum prior to abdominal closure.Following successful establishment of adhesion model,the Qingchang mixture group received a daily oral gavage of 2 mL Qingchang mixture(14.58 g/kg),while the other four groups were given equal volume normal saline administration.In each group,five rats were euthanized on postoperative days 3,7 and 14 to assess abdominal adhesions using Nair's scoring system.Adhesive tissue or normal peritoneal tissue were harvested on postoperative day 7,and mRNA expression levels of interleukin-4(IL-4),signal transducer and activator of transcription 6(STAT-6)and interferon-γ(IFN-γ)were quantified via fluorescence-based real-time PCR.Concurrently,Western blot analysis was employed to evaluate protein expression levels of IL-4,interleukin-10(IL-10),STAT-6 and IFN-γ.Pathological alterations in adhesive tissue were visualized using hematoxylin-eosin(HE)staining under light microscopy,and inflammation and fibrotic changes were assessed accordingly.Results Compared with the blank and sham-operated groups,mRNA and protein expression levels of IL-4 and STAT-6 were significantly downregulated in the model group,protein expression level of IL-10 was also reduced.Conversely,the mRNA and protein expression levels of IFN-γ,as well as the inflammation and fibrosis scores were significantly elevated(P＜0.05).In comparison to the model group,IL-4 and STAT-6 mRNA and protein expression levels were increased in the Qingchang mixture group and the hyaluronic acid group,along with an increase in IL-10 protein expression.Conversely,these groups exhibited a significant reduction in Nair's scores,inflammation scores,fibrosis scores,and IFN-γ mRNA and protein expression levels were decreased(P＜0.05).Conclusion Qingchang mixture appears to suppress the development of postoperative peritoneal adhesions,likely through mechanism that involves modulating the expression of T-helper 1 and T-helper 2 cytokines,thereby attenuating inflammatory response.