AIMS The aim of the study was to obtain further information regarding the modes of action of doxazosin, naftopidil and nifedipine on platelet function. METHODS We conducted an in vitro study of drug influences on adrenaline and collagen-induced mobilization of platelet calcium. RESULTS In the presence of fibrinogen (300 micrograms ml-1) both collagen (5 micrograms ml-1) and adrenaline (16 m...

Renal cell carcinoma (RCC) is an angiogenesis-dependent and hypoxia-driven malignancy. As a result, several targeting agents are being investigated. However, the efficacy of current regimens is generally insufficient for their toxicity and poor overall response rates. We have recently reported that naftopidil exerts growth-inhibitory effects on human prostate cancer cells. In this study, we inv...

We compared the efficacy of naftopidil with that of tamsulosin hydrochloride for benign prostatic hyperplasia patients. Eighty-five patients without improvement of quality of life (QOL) score by the administration of 50-75 mg naftopidil for more than four weeks were assigned to receive doses of 0.1-0.2 mg tamsulosin hydrochloride and 89 patients without improvement of QOL score by the administr...

Naftopidil, approved only in Japan, is an α1-adrenergic receptor antagonist (α1-blocker) used to treat lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH). Different from tamsulosin hydrochloride and silodosin, in that it has higher and extremely higher affinity respectively, for the α1A-adrenergic receptor subtype than for the α1D type, naftopidil has distinct ...

OBJECTIVES To evaluate the lower urinary tract symptoms predicting the efficacy of the α1-adrenoreceptor (AR) antagonist naftopidil in patients with benign prostate hyperplasia. METHODS The efficacy of naftopidil was examined on the basis of changes in the international prostate symptom score (IPSS). All patients received naftopidil (50 mg/day) for 12 weeks. We defined a "responder" as a pati...

PURPOSE Benign prostatic hyperplasia (BPH) impacts quality of life in men by causing lower urinary tract symptoms. α1-Adrenoceptor (α1-AR) blockers improve lower urinary tract symptoms. We investigated the efficacy of add-on therapy with α1-AR blockers on BPH rats. METHODS Rats in the drug-treated groups were orally administered each drug once a day for 30 days after orchiectomy. To induce BP...

BACKGROUND Naftopidil, an α1-adrenoceptor blocker, has been clinically used for the treatment of benign prostate hyperplasia and hypertension. Emerging evidence has shown that naftopidil exhibits an antitumor effect on a variety of cancer types including prostate cancer. The aim of the present study was to investigate naftopidil-induced apoptosis in human malignant mesothelioma cells and to she...

PURPOSE Overactive bladder (OAB) causes urinary urgency, usually accompanied by frequency and nocturia. Alpha 1-adrenergic receptor (α1-AR) antagonists are known to improve lower urinary tract symptoms associated with OAB. The α1-AR antagonists constitute a variety of drugs according to the receptor subtype affinity. This study investigated the efficacy of tamsulosin, naftopidil, and a combinat...

AIMS We examined the mechanism of action of naftopidil, an α1D/A blocker, on spinal descending serotonergic neurotransmission for the micturition reflex. METHODS We examined (1) urinary 5-hydroxyindole acetic acid (5-HIAA) after intraperitoneal administration of saline, para-chlorophenylalanine (PCPA; a serotonin synthetic enzyme inhibitor), and/or 5-hydroxytryptophan (5-HTP; a serotonin prec...

AIMS Alpha1-blockers improve voiding symptoms through the reduction of prostatic and urethral smooth muscle tone; however, the underlying mechanism of improvement of storage symptoms is not known. Using a rat model of detrusor overactivity caused by cerebral infarction (CI), we undertook the present study to determine whether the effect of an alpha1-blocker, naftopidil, is dependent on the supp...