Background: Although alpha-adrenergic blockers are widely used as a treatment of benign prostatic hyperplasia (BPH), it is not clear whether contractile property of hyperplastic prostate to alpha-adrenergic agonist depends upon an area of density of smooth muscle within the respective BPH tissue.
Methods: Functional study and quantitative morphometric analysis were performed on human prostatic specimens obtained by transurethral resection from 22 men with symptomatic BPH. Tissue norepinephrine content was also evaluated.
Results: There was a linear correlation between the area of density of smooth muscle and maximum response to phenylephrine (r = 0.457, P = 0.0362). Although the area of density of smooth muscle showed a positive correlation with norepinephrine content (r = 0.437, P = 0.0471), norepinephrine content was not correlated with maximum phenylephrine response.
Conclusions: Contractile response to alpha-adrenergic agonist was directly influenced by the area of density of the smooth muscle within an individual prostate.