Masaharu Nakai

Ultrasound-Estimated Bladder Weight Predicts Risk of Surgery for Benign Prostatic Hyperplasia in Men Using α-Adrenoceptor Blocker for LUTS

OBJECTIVES Although invasive and expensive, the pressure-flow study is known as the reference standard for the diagnosis of bladder outlet obstruction. We investigated the usefulness of ultrasound-estimated bladder weight (UEBW) as a predictor of the need for surgery for benign prostatic hyperplasia (BPH). METHODS A total of 97 consecutive male patients >50 years old with lower urinary tract symptoms (LUTS) were prospectively enrolled in this study. The surgery rate was correlated with the UEBW, the results of uroflowmetry, the postvoid residual urine volume, prostate volume, and International Prostate Symptom Score. RESULTS Surgery for BPH was performed in 37 of the 97 patients studied. The surgery rate was associated with a high UEBW (>or=35 g), severe LUTS (International Prostate Symptom Score of >or=20), a voided volume of <100 mL at free uroflowmetry, and poor uroflow (maximal flow rate of <10 mL/s). Multivariate analysis revealed that severe LUTS and a high UEBW were the risk factors for surgery for BPH. CONCLUSIONS The results of our study have shown that the UEBW can be regarded as a useful parameter to identify patients with LUTS who are at risk of needing surgery for BPH.

Acetylcholinesterase inhibitor acting on the brain improves detrusor overactivity caused by cerebral infarction in rats

PURPOSE The functional contribution of the cholinergic pathway in the frontal cortex to micturition was evaluated following cerebral ischemia. Furthermore, it was examined whether reactivation of this regulatory system using acetylcholinesterase inhibitor could improve detrusor overactivity. METHODS Left middle cerebral artery occlusion (MCAO) was performed in female Sprague-Dawley rats. Choline acetyltransferase (ChAT) activities after MCAO were assayed to assess the damage to cholinergic neurons. ChAT activities in the bilateral cortex, hippocampus, and pons were calculated by measuring the conversion of 1-[14C] acetyl-coenzyme A to [14C] acetylcholine. Effects on cystometrography of i.v. or i.c.v. donepezil hydrochloride (DON), a centrally acting acetylcholinesterase inhibitor, were investigated in conscious sham-operated (SO) and cerebral infarcted (CI) rats. To investigate whether DON in the forebrain was affected, we decerebrated rats after CI or SO, and investigated the effects on cystometrography of i.v. DON. RESULTS Bladder capacity was markedly decreased after MCAO, and remained below half of the pre-occlusion capacity. The greatest increase in bladder capacity was attained at 1.2 x 10(-2) nM/kg of DON given i.v., with a change of 52.8% (P < 0.05). In cases of i.c.v. DON, the greatest increase in bladder capacity was at the dose of 6 x 10(-2) pmol with the change of 95.8% (P < 0.01). The activity of ChAT was decreased in the left cortex and hippocampus 24 h after MCAO (P < 0.05). In decerebrated rats, low dose of DON did not change micturition parameters. CONCLUSIONS These results suggest that by upregulation of the forebrain muscarinic inhibitory mechanism, acetylcholinesterase inhibitor improves detrusor overactivity by cerebral infarction.