ObjectiveTo observe the expression of inflammatory cytokines in diabetic rats received posterior sub-Tenon capsule injection of triamcinolone acetonide (TA) and pan-retinal photocoagulation. MethodsA total of 48 Brown Norway rats received intraperitoneal injection of streptozotocin to establish the diabetic model. Diabetic rats were randomly divided into experimental group (20 rats), control group (20 rats) and blank group (8 rats). 50 μl TA or saline was injected into the posterior sub-Tenon capsule immediately after the photocoagulation in the experimental group and the control group, respectively. The blank group received no treatment. The mRNA and protein expression level of retinal vascular endothelial growth factor (VEGF), interleukin-6 (IL-6) and tumor necrosis fator-α (TNF-α) were measured by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA) at 1, 3, 7 days after laser photocoagulation. ResultsThe mRNA and protein expression of VEGF, IL-6, TNF-α of the experimental group and control group were significantly higher than the blank group, the difference was statistically significant (P < 0.05). The mRNA and protein expression of VEGF, IL-6 and TNF-α of the experimental group were significantly lower than that of the control group. On day 1 after laser photocoagulation, the mRNA expression of VEGF was not statistically significant in the experimental group and control group (P > 0.05), the mRNA and protein expression of VEGF, IL-6, TNF-α of the two groups were statistically significant in the remaining observing time (P < 0.05). ConclusionPosterior sub-Tenon capsule injection of TA can effectively reduce retinal photocoagulation induced VEGF, IL-6, TNF-α expression.