BPH 14. Subtypes of α1 - adrenergic receptor in those with hypertension and prostatic hyperplasia

Objective: α1-adrenergic receptor is closely correlated with high blood pressure and prostatic hyperplasia. This study observed the subtypes changes of α1-adrenergic receptorso as to explore the mechanism of hypertension formation and progression in those with primary hypertension and benign prostatic hyperplasia (BPH), in a hope to guide for clinical treatment.

Methods: 47 fresh prostate specimens, from those who underwent transurethral prostatic resection and were pathologically confirmed with BPH, were divided into single BPH group and hypertension/BPH group according to clinical standard of hypertension. RT-PCR was used to evaluate the mRNA expression of α1 receptor subtypes in resected prostate tissues for comparative analysis.

Results: Among the 47 cases, 23 were with single BPH (49%), while 24 had both hypertension and BPH (51%); mean ages of single BPH and of hypertension combined with BPH were 72.48 and 72.39 respectively (P>0.05); mean prostate volumes of single BPH and of hypertension combined with BPH were 58.7±8.41 cm³ and 69.0±23.86 cm³ respectively (P>0.05); mean preoperative IPSS scores in single BPH and hypertension combined with BPH were 21.09±2.67and 25±2.3 respectively (P<0.05). Although the total expression of α1 receptor mRNA in hypertension and BPH group 66.71±15.5 μg/mL had no significant difference with the single BPH group 58.09±14.7 μg/mL (P>0.05), the expression level of α1-adrenergic receptor subtype mRNA changed: α1A receptor mRNA expression level in hypertensive patients with BPH 29.8±6.44 μg/mL was significantly higher than in single BPH patients 13.14±5.09 μg/mL (P<0.05); expression level of α1Dadrenergic receptor mRNA in hypertensive patients with BPH 15.67±4.75 μg/mL was significantly lower than single BPH group 26.9±6.45 μg/mL (P<0.05); while expression of α1B-adrenergic receptor mRNA in hypertensive patients with BPH group 21.25±5.61 μg/mL had no significant difference with that in single BPH group 18.05±4.0 μg/mL. In single BPH group, the expression proportion of α1A, α1B, and α1D was 22.6%:31.1%:46.3%, with α1D receptor expression in the dominant position (P<0.05); in hypertensive patients with BPH, the proportion of the three kinds of receptors was 44.6%:31.9%:23.5%, withα1A receptor expression in the dominant position (P<0.05).

Conclusions: Expression of α1A-adrenergic receptor mRNA in hypertensive patients with BPH was significantly higher than in single BPH patients. Inhibiting the function of α1A-adrenergic receptor subtypes may benefit hypertension and BPH patients for clinical treatment of their lower urinary tract symptoms.