Objective To study the effects of photodynamic therapy (PDT) combined with torasemide on rat glioma by detecting the protein expression of matrix metalloproteinase 2 (MMP2),matrix metalloproteinase 9 (MMP9),sodium-potassium-chloride co-transporter 1 (NKCC1) and vascular endothelial growth factor (VEGF).Methods Male Wistar rats with glioma were randomly divided into four groups,includes control group (sham group,n=15),photodynamic therapy group (PDT group,n=15),torasemide group (T group,n=15) and PDT+T group (n=15).The rats were normally fed in the sham group,were received PDT (80 J/cm2) for 10 min in the PDT group,were received intraperitoneal torasemide 5 mg/kg for 3 days in the T group,and received PDT and torasemide treatment in the PDT+T group.After 2 weeks,5 rats were sacrificed from each group.Peritumoral edema tissues were harvested for the detection of wet-dry-weight ratio (W/D),and the protein expression of MMP2,MMP9,NKCC 1 and VEGF by Western Blot,immunohistochemistry and qRT-PCR.The remaining rats were used for survival time assessment.Results Compared with the sham group,the PDT group showed an increase in W/D (5.17±0.42 vs 4.83±0.38),the expression of NKCC1 (0.54±0.21 vs 0.35±0.12) and VEGF (0.68±0.20 vs 0.42±0.15),and survival time ((32.2±2.9) d vs (25.3±2.6) d) (all P＜0.05),and showed an decrease in the expression of MMP2 (2.76±0.42 vs 1.88±0.17) and MMP9 (2.55±0.38 vs 1.46±0.21) (all P＜0.05).Compared with the PDT group,the T group showed decrease in W/D (3.68±1.04),the expression of NKCC1 (0.22±0.10) and VEGF (0.33±0.14),and survival time ((28.7±2.2) d) (all P＜0.05),and showed increase in the expression of MMP2 (2.71 ±0.35) and MMP9 (2.42±0.36) (all P＜0.05).Compared with the PDT group,the PDT+T group showed decrease in W/D (4.52±0.46),and the expression of NKCC1 (0.30±0.16),VEGF (0.44±0.21),MMP2 (1.84±0.23) and MMP9 (1.53±0.24) (all P＜0.05),and showed increase in survival time ((44.5±2.8) d)(P＜0.05).Conclusion PDT combined with torasemide can reduce PDT induced edema,reduce tumor invasiveness,and prolonged the average survival time of rats.