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Updated: Mar 28, 2026

Ultrasonography of the Adult Male Urinary Tract for Urinary Functional Testing
Published on: August 14, 2019
Correlation Between Bladder Mucosal Alpha-1D/Alpha-1A Adrenoceptor mRNA Ratio and Lower Urinary Tract Function in
Yoshiki Kurizaki1, Osamu Ishizuka1, Tetsuya Imamura1
1Department of Urology, Shinshu University School of Medicine, Matsumoto, Japan.
Objectives:
Alpha-1 adrenoceptor (AR) antagonists are commonly used as therapeutic agents for patients with benign prostatic obstruction (BPO). Our objective was to investigate the correlation between the ratio of bladder mucosal alpha-1D/alpha-1A adrenoceptor mRNA and lower urinary tract function in BPO patients.
Methods:
In 20 BPO patients, the expression level of alpha-1 AR mRNAs in the bladder mucosal biopsies was investigated by reverse transcriptase polymerase chain reaction. The subjects were divided into two groups. In Group 1, the ratio of alpha-1D mRNA to alpha-1A mRNA was greater than one. In Group 2, the ratio was less than one. We determined the correlation by Schäfer nomogram between Group 1 and Group 2 patients and lower urinary tract function as determined by a video urodynamic study.
Results:
Two patients were excluded due to inability to void. Another was excluded because the alpha-1D/alpha-1A mRNA ratio was one. On the Schäfer nomogram, six of nine Group 1 cases had obstructions less than IV and normal or weak detrusor contractility. For Group 2, six of eight cases had obstructions more than IV and normal or strong detrusor contractility.
Conclusion:
Patients with higher levels of alpha-1D AR mRNA were distinct from those with higher alpha-1A AR mRNA levels with regard to obstruction and detrusor activity. The results suggest that the Schäfer nomogram might be useful in determining which alpha-1 AR antagonists are better for BPO patients suffering from storage symptoms.
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