Harunori Narita

Evidence for contractility of the human seminiferous tubule confirmed by its response to noradrenaline and acetylcholine

The experiments reported here demonstrate for the first time that the isolated human seminiferous tubule is capable of undergoing contraction after exposure to noradrenaline and acetylcholine. Isoproterenol produces a relaxation of the seminiferous tubule. It is indicated that there are the adrenergic alpha and beta receptors and muscarinic receptors in the myoid cells of human seminiferous tubules.

Renal Hypertension Secondary to Perirenal Pseudocyst: Resolution by Percutaneous Drainage

We report a case of renal hypertension 6 months after a panhysterectomy for cervical cancer. Clinical investigation revealed that recurrent cancer obstructed the left ureter, resulting in the formation of a gigantic perirenal pseudocyst and, subsequently, hypertension. Constriction of the renal parenchyma was responsible for the overactivity of the renin-angiotensin system (the Page phenomenon). Ultrasound-guided percutaneous drainage relieved the symptomatology completely.

Comparison of Silodosin and Naftopidil for Efficacy in the Treatment of Benign Prostatic Enlargement Complicated by Overactive Bladder: A Randomized, Prospective Study (SNIPER Study)

Purpose: We investigated the efficacy of 2 &agr;1‐blockers with different affinities for the &agr;1‐adrenoceptor subtypes silodosin and naftopidil in the treatment of benign prostatic enlargement complicated by overactive bladder. Materials and Methods: This was a prospective, open label, randomized, multicenter study of 350 outpatients with untreated benign prostatic enlargement associated with urinary urgency at least once per week and an OABSS (Overactive Bladder Symptom Score) of 3 or greater. Patients were randomly assigned to receive silodosin 8 mg per day or naftopidil 75 mg per day. Changes in parameters from baseline to 4 and 12 weeks were assessed based on I‐PSS (International Prostate Symptom Score), I‐PSS quality of life, OABSS and voiding functions measured by uroflowmetry. Results: On efficacy analysis a total of 314 patients were included in the 2 groups. No significant difference in adverse effects was observed between the groups. Mean I‐PSS and I‐PSS quality of life scores, and OABSS significantly improved in both groups. Statistically significantly greater improvement in the silodosin group than in the naftopidil group was observed in total OABSS (p = 0.03), I‐PSS quality of life score (p = 0.005) and OABSS urgency score (p <0.001) at 12 weeks. In regard to voiding function the maximum urinary flow rate showed significant improvements in both groups but the change in the maximum flow rate in the silodosin group at 12 weeks was significantly greater than in the naftopidil group (3.6 vs 2.1 ml per second). Conclusions: Silodosin, a pure &agr;1A‐adrenoceptor blocker, showed greater improvement in overactive bladder symptoms along with the urinary flow rate in patients with benign prostatic enlargement complicated by overactive bladder compared to naftopidil, an &agr;1D>A‐adrenoceptor blocker.

Effect of prostaglandin on urethral resistance and micturition.

SummaryThe effect of four exogenous prostaglandins, PGA1, PG802, PGE2 and PGF2α, upon the lower urinary tract was investigated in female mongrel dogs without neurogenic lesions in vivo. The urethral resistance was studied by means of a urethral pressure profile, and the bladder function by evaluating whether or not the micturition was triggered. The reduction of urethral resistance in terms of the maximum urethral closure pressure was most significant with PGE2 given intraarterially. Micturition was most frequently provoked by the intravenous administration of PG802, a derivative of PGE1. PGE series seemed to be the most potent for the evacuation of urine in female dogs.

Correlations among Lower Urinary Tract Symptoms, Bother, and Quality of Life in Patients with Benign Prostatic Hyperplasia and Associated Fluctuations with Tamsulosin Administration

Objectives: To estimate correlations among lower urinary tract symptoms (LUTS), bother, and quality of life (QOL) and assess fluctuations in these parameters after α1‐blocker administration in patients with benign prostatic hyperplasia (BPH).