P 07. The rapeutical effect of Tacrolimus on Autoimmune Prostatitis in rat model and preliminary study on its mechanism

Objective: To explore the efficacy of tacrolimus in treating experimental autoimmune prostatitis in rat model and its mechanism.

Methods: SD rats were randomly divided into 4 groups, namely normal control group, EAP model group, low-dose treatment group, high-dose treatment group. According to administration duration, each group was further divided into two subgroups: 2-week group and 4-week group. After successful modeling, rats in low-dose treatment group and high-dose group underwent gastric perfusion with 0.2 mg.kg^-1.d^-1 and 0.8 mg.kg^-1.d^-1 tacrolimus respectively for 2 and 4 weeks in a successive way. Concentrations of IL-2 and MIP-1α in the homogenate of prostatic tissue and serum were tested. Histomorphological changes of prostatic tissue, spleen and thymus gland were observed, with their viscera coefficients being calculated.

Results: After the intervention of tacrolimus, a decrease in inflammatory cells in prostatic tissue was revealed histomorphologically and glandular cavity wall was repaired to some extent. concentrations of IL-2 were varied as 156.80±19.11, 124.56±17.2 and 114.46±20.65 in the serum of M2W, L2W and H2W group, while MIP-1α concentrations were 164.99±22.25, 112.03±19.9 and 104.91±11.91 pg/mL respectively. As for the homogenate of prostatic tissue, IL-2 and MIP-1α levels stood at 219.26±23.11, 191.56±19.08, 186.63±20.9 and 216.46±18.50, 196.55±17.84, 194.74±18.14 pg/mL respectively. In comparison, in M4W, L4W and H4W group, concentrations of the two substances were 156.23±19.83, 129.27±17.25, 134.26±16.11 and 157.93±34.55, 159.09±29.17, 154.54±29.85 pg/mL. Whereas in the homogenate of prostatic tissue, data were 217.92±23.23, 186.07±11.56, 180.37±18.26 and 209.66±14.65, 186.17±17.79, 186.16±18.27 pg/mL. All differences were statistically significant except MIP-1α level in the serum of 4-week group.

Conclusions: Tacrolimus can reduce the number of inflammatory cells in prostatic tissue in EAP Rat model. This effect may be related to its suppression of the production of IL-2 and activation of T cells.