Purpose: To investigate the effect of Phellodendron chinense Schneid (PCS)  extracts on carrageenan-induced chronic prostatitis in rats.

Methods: Experimental chronic non-bacterial prostatitis (CNP) was induced in rats by injecting carrageenan into prostatitis. Rats in treated groups were administered either PCS extract or positive control (cernilton) for 3 weeks while those in the control group received saline instead. After treatment, prostate index (PI) and prostate-specific antigen (PSA) of all rats were examined by ELISA. The degree of chronic inflammatory cell infiltrates, acinar changes and interstitial fibrosis were evaluated by histopathological examination. In addition, relative inflammatory factors, viz, tumor necrosis factor-α (TNF-α), interleukin1β (IL-1β), cyclooxygenase-2 (COX-2), prostaglandin E2 (PEG₂), transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) of prostate tissues of all the rats were measured by ELISA.

Results: High-dose PCS (400 mg/kg) significantly decreased PI (1.0 ± 0.1 mg/ml) relative to reference group (2.1 ± 0.2, p < 0.01) while high-dose PCS (400 mg/kg) significantly decreased PSA level (154.2 ± 14.3 pg/ml) relative to the reference group (312.5 ± 20.5 pg/ml, p < 0.01). Morphometric analysis demonstrated the presence of chronic inflammatory cell infiltrates, and interstitial fibrosis decreased significantly compared to the reference group. Compared with reference group (165.4 ± 14.2 pg/ml), TNF-α level in the prostate tissues of high-dose PCS group rats decreased (116.5 ± 9.3) significantly (p < 0.01). Similarly, compared with reference group (176.1 ± 12.1 pg/ml), IL-1β level of prostate tissues of high-dose PCS group rats decreased (97.6 ± 11.3) significantly (p < 0.01).

Conclusion: PCS extract has significant therapeutic effect on carrageenan-induced chronic prostatitis in rats.