Doxazosin mesylate affects localization of endothelin-1 in prostatic tissues

Introduction. Data suggest that not only alpha-adrenergic factors contribute to contractility of smooth muscles of the prostate. The authors determined the influence of doxazosin mesylate on localization of endothelin-1 in prostatic tissue in treated and non-treated patients. Material and methods. Seventy patients with symptoms of prostate enlargement: 40 patients preliminary treated with doxazosin mesylate and 30 non-treated patients. All underwent prostate biopsy due to elevated PSA level (mean 5.85 ng/ml). Specimens were H&E stained for histopathology which confirmed diagnosis of benign hyperplasia and immunohistochemically stained for ET-1 in epithelium and prostate stroma. Authors calculated ET-1 mean optical density ratios (epithelial ET-1/stromal ET-1) for treated and non-treated patients. Statistical analysis was performed. Ratios of ET-1 in epithelium and stroma of both groups differed statistically. Conclusions. Obtained data indicate that relocation of endothelin-1 from prostate epithelium to stroma is altered in the treated group in comparison with the non-treated group. Doxazosin mesylate might have an influence on ET-1 redistribution from the epithelial compartment to the non-epithelial environment. This could be an additional mechanism of action of alpha-adrenergic blockers in BPH patients.