Terazosin treatment suppresses basic fibroblast growth factor expression in the rat ventral prostate

Alpha1-adrenergic receptor antagonists may not act solely on smooth muscle contractility. We evaluated the in vivo effect of the alpha1 blocker, terazosin, on the expression of basic fibroblast growth factor (bFGF) in the rat ventral prostate. Wistar rats were treated with terazosin (1.2 mg/kg body weight, po, every second day) for 120 days. The expression of bFGF was assessed immuno-histochemically in tissue sections and by Western blotting in whole tissue preparations. Terazosin treatment did not affect prostate weight or histomorphology. In the control group, epithelial and stromal cells demonstrated positive staining for the anti-bFGF antibody. In contrast, the same staining in terazosin-treated specimens was either absent or extremely weak. An analogous difference was observed among the corresponding immunoblots. These findings implicate the reduction of bFGF expression by terazosin as a potential additional molecular mechanism of its action that may include alterations in peptide growth factor mediated prostate homeostasis.