Influence and pathophysiological mechanisms of simvastatin on prostatic hyperplasia in spontaneously hypertensive rats.

OBJECTIVE: To explore the effects and mechanisms of simvastatin on prostate hyperplasia in spontaneously hypertensive rats (SHRs). METHODS: Thirty-six male SHRs were randomly divided into three groups: the 10 and the 20 mg/kg/d simvastatin group and the control group. After 6 weeks the ultra-microscopic prostate structures were observed. The serum levels of interleukin-6 (IL-6), insulin-like growth factor (IGF-1) and angiotensin II (Ang-II) were measured by enzyme-linked immunosorbent assays. The endothelium-derived nitric oxide synthase (eNOS) expression was evaluated with immunohistochemistry. RESULTS: Compared to the control group, the 20 mg/kg/d simvastatin group presented with lower absolute (p = 0.005) and relative prostate weight (p = 0.009). The basal cells and columnar cells presented with edema, condensed heterochromatin in interstitial fibroblast nuclei, widened nucleus gaps, and decreased mitochondria and endoplasmic reticulum in the 10 mg/kg/d simvastatin group, these changes were more pronounced in the 20 mg/kg/d simvastatin group. The IL-6 levels in the 10 and 20 mg/kg/d simvastatin groups were lower than those of the controls (p = 0.005 and p = 0.008). The IGF-1 levels of the 20 mg/kg/d simvastatin group were reduced compared to the control group (p = 0.016). CONCLUSIONS: Simvastatin can delay and inhibit prostatic hyperplasia and progression in SHR. These actions may be mediated through the suppression of inflammatory and growth factors.