Correlation between expression of α1-adrenoceptor subtype mRNA and severity of lower urinary tract symptoms or bladder outlet obstruction in benign prostatic hyperplasia patients

Abstract

To examine whether the direct correlation between the expression of α₁-adrenoceptor (AR) subtype mRNA and severity of lower urinary tract symptoms (LUTS) or bladder outlet obstruction (BOO) in the prostate exists in benign prostatic hyperplasia (BPH) patients. Sixty-eight patients with LUTS and BOO secondary to BPH were enrolled. Four prostate needle biopsy specimens were obtained from the transition zone to examine the expression level of α₁-AR subtypes by Taqman reverse-transcription polymerase chain reaction. The correlation and regression between each expression level of α₁-AR subtype and clinical findings such as patient age, prostate volume, International Prostate Symptom Score (IPSS), quality of life (QOL) index, maximum flow rate in uroflowmetry (Qmax) and post-void residual urine volume (PVR) were assessed by stepwise multiple regression analysis. The correlation and regression between this expression level and individual symptoms of IPSS were assessed by Pearson's correlation coefficient and multiple regression analyses. Stepwise multiple regression analysis showed that the expression levels of α(1a) -AR, α(1b) -AR, α(1d) -AR and total α(1) -AR mRNA showed a significant regression with patient age, but not with prostate volume, IPSS, QOL index, Qmax and PVR. Pearson's correlation coefficient and multiple regression analyses demonstrated no correlation and regression between each α(1) -AR subtype mRNA expression level and individual symptoms of IPSS. There was no direct correlation between the expression of α₁-AR subtype mRNA in the prostate and severity of LUTS or BOO in BPH patients, although the significant regression of this expression with patient age existed. LUTS and BOO may be associated with multiple factors and several other conditions may contribute to LUTS and BOO.