Terazosin hydrochloride (Hytrin) , a selective alpha1-antagonist, can treat the benign prostatic hyperplasia (BPH). It also can lower blood pressure, so it is a drug of choice for patients with prostate enlargement and hypertension. It works on the smooth muscle of the bladder and the blood vessel walls by blocking the function of adrenaline.

Terazosin induces cytotoxicity in PC-3 and human benign prostatic cells with an IC50 of more than 100 μM. Terazosin also effectively inhibited vascular endothelial growth factor induced proliferation and tube formation in cultured human umbilical vein endothelial cells (IC50 9.9 and 6.8 μM, respectively)[3].

Terazosin produces a dose-dependent, complete inhibition of motor activity and catalepsy. Intraventricularly administered this antagonist protects striatal and cerebral cortical alpha 1 receptors but not striatal or cortical D1 receptors from in vivo alkylation by N-ethoxycarbonyl-2-ethoxy-1,2-dihydroxyquinoline. Intraventricular terazosin also produces hypothermia and a reduced respiratory rate suggestive of a reduced sympathetic outflow. Terazosin does not impair performance on a horizontal wire test or the ability to make co-ordinated movements in a swim test[2].Terazosin significantly inhibits vascular endothelial growth factor induced angiogenesis in nude mice with an IC50 of 7.9 μM, showing that it has a more potent anti-angiogenic than cytotoxic effect[3].

To determine the cytotoxic effect mode of action, several identification techniques were used in the current study. Apoptotic cells are detected in situ using terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling. Results show a positive reaction after a 12-hour treatment of PC-3 cells with terazosin (100 μM). (Only for Reference)