What is the primary action of alpha-adrenergic blockers in relation to the prostate?

Alpha-adrenergic blockers primarily work by relaxing smooth muscle in the prostate and the bladder neck. This relaxation leads to a reduction in resistance to urine flow, allowing for easier passage of urine, which is particularly beneficial for patients experiencing benign prostatic hyperplasia (BPH). By targeting alpha-1 adrenergic receptors predominantly found in the prostate, these medications alleviate urinary symptoms associated with enlarged prostate, such as difficulty starting urination or weak urine stream. Thus, the correct choice reflects the direct mechanism by which alpha-adrenergic blockers facilitate improved urinary function by enhancing urine flow through prostate smooth muscle relaxation.