Insights into the associative role of hypertension and angiotensin II receptor in lower urinary tract dysfunction.

In men, the lower urinary tract comprises the urinary bladder, urethra, and prostate, and its primary functions include urine storage and voiding. Hypertension is a condition that causes multi-organ damage and an age-dependent condition. Hypertension and the renin-angiotensin system activation are associated with the development of lower urinary tract dysfunction. Hypertensive animal models show bladder dysfunction, urethral dysfunction, and prostatic hyperplasia. In the renin-angiotensin system, angiotensin II and the angiotensin II type 1 receptor, which are expressed in the lower urinary tract, have been implicated in the pathogenesis of lower urinary tract dysfunction. Moreover, among the several antihypertensives, renin-angiotensin system inhibitors have proven effective in human and animal models of lower urinary tract dysfunction. This review aimed to elucidate the hitherto known mechanisms underlying the development of lower urinary tract dysfunction in relation to hypertension and the angiotensin II/angiotensin II type 1 receptor axis and the effect of renin-angiotensin system inhibitors on lower urinary tract dysfunction. Possible mechanisms through which hypertension or activation of Ang II/AT1 receptor axis causes LUTD such as bladder dysfunction, urethral dysfunction, and prostatic hyperplasia. LUT: lower urinary tract, LUTD: lower urinary tract dysfunction, AT1: angiotensin II type 1, ACE: angiotensin-converting enzyme.

Cyanoacrylate closure for arteriovenous fistula in the lower extremity with saphenous vein insufficiency.

A lower extremity arteriovenous fistula (AVF) is sometimes associated with venous disease following venous hypertension, especially when the saphenous vein is the main return route. This can cause venous dilation, leading to valve insufficiency. A complete cure can be difficult in cases with multiple vascular branches. We report three surgical cases of lower extremity AVF with saphenous vein insufficiency. All patients had saphenous vein insufficiency with long duration leg symptoms and underwent full-length occlusion of saphenous vein using cyanoacrylate closure. Substantial improvements in leg symptoms and appearance were observed immediately after surgery in all three patients. Cyanoacrylate closure could be a treatment option for lower extremity AVF.

Endoscopic Transpapillary Gallbladder Drainage for Recurrent Cholecystitis after Covered Self-expandable Metal Stent Placement for Unresectable Malignant Biliary Obstruction.

A 76-year-old woman with advanced pancreatic cancer developed recurrent cholecystitis after covered self-expandable metal stent (CSEMS) placement. The cholecystitis was refractory to repeated percutaneous transhepatic gallbladder drainage (PTGBD). Cholecystography showed a patent cystic duct with right and cranial side bifurcation, which is indicative of an increased likelihood of success of endoscopic transpapillary gallbladder drainage (ETGBD). We were able to manage the cholecystitis by ETGBD without further recurrence. ETGBD is considered an effective internal drainage method for the management of acute cholecystitis after CSEMS placement, and its indication may be decided on the basis of the findings of cholecystography through the PTGBD route.

Changes in ALBI Score and PIVKA-II within Three Months after Commencing Atezolizumab Plus Bevacizumab Treatment Affect Overall Survival in Patients with Unresectable Hepatocellular Carcinoma.

In this study, we aimed to evaluate the efficacy and safety of atezolizumab plus bevacizumab (Atez/Bev) treatment for unresectable hepatocellular carcinoma (HCC) and to analyze the factors affecting overall survival (OS). A total of 69 patients who received Atez/Bev at our institutions for unresectable HCC were enrolled in this study. OS and progression-free survival (PFS) were estimated using the Kaplan−Meier method. Changes in clinical indicators within 3 months were defined as delta (∆) values, and the Cox proportional hazards model was used to identify which ∆ values affected OS. The median OS, PFS, objective response rate, and disease control rate were 12.5 months, 5.4 months, 23.8%, and 71.4%, respectively. During the observational period, 62 patients (92.5%) experienced AEs (hypertension (33.3%) and general fatigue), and 27 patients (47.4%) experienced grade ≥ 3 AEs (hypertension (10.1%) and anemia (7.2%)). There was a significant deterioration in the albumin-bilirubin (ALBI) score (−2.22 to −1.97; p < 0.001), and a reduction in PIVKA-II levels (32,458 to 11,584 mAU/mL; p = 0.040) within 3 months after commencing Atez/Bev. Both the worsening ∆ ALBI score (p = 0.005) and increasing ∆ PIVKA-II (p = 0.049) were significantly associated with the OS of patients.

Endoscopic Internalization by Cutting the Endoscopic Transpapillary Nasogallbladder Drainage Tube in Management of Acute Cholecystitis: A Retrospective Multicenter Cohort Study.

BACKGROUND: Both endoscopic nasogallbladder drainage (ENGBD) and endoscopic gallbladder stenting (EGBS) are effective management for acute cholecystitis, although ENGBD can cause discomfort due to its nature of external drainage. Converting ENGBD to EGBS after improvement of cholecystitis might be one treatment strategy. The drainage tube of ENGBD could be endoscopically cut inside the stomach to convert to internal drainage without additional endoscopic retrograde cholangiography (ERCP). AIMS: To evaluate the feasibility, efficacy and safety of endoscopic internalization by cutting an ENGBD tube for acute cholecystitis. METHODS: Twenty-one patients who underwent endoscopic internalization by cutting the ENGBD tube were enrolled in this study. We initially placed an ENGBD tube for gallbladder lavage and continuous drainage. After improvement of cholecystitis, the tube was cut in the stomach by esophagogastroduodenoscopy (EGD) and placed as EGBS until surgery. RESULTS: The technical success rate of this procedure was 90.5% (19/21), and the clinical success rate was 100% (19/19). The median procedural time was 5 min (range: 2-14 min). Procedural-related adverse events (AEs) were observed in two patients where the tip of the ENGBD tube migrated into the common bile duct from the gallbladder during the procedure in both. During the waiting period for elective surgery, no AEs were identified, except for stent migration without symptoms in one patient (4.7%). CONCLUSION: Endoscopic internalization by cutting the ENGBD tube after improvement of cholecystitis could be an effective and safe treatment option for preventing recurrent cholecystitis in the waiting period until cholecystectomy.

Protective effects of hydrogen sulfide pretreatment on cyclophosphamide-induced bladder dysfunction in rats via suppression of bladder afferent nerves.

Cyclophosphamide (CYP), a broad-spectrum anticancer drug, causes serious side effects, such as haemorrhagic cystitis (HC). Hydrogen sulfide (H2S), an endogenous gasotransmitter, has physiological properties, including anti-inflammation, anti-oxidation, and neuromodulation. In this study, we investigated the effects of NaHS (H2S donor) pretreatment on bladder dysfunction in CYP-treated rats. Male Wistar rats were intraperitoneally pretreated with NaHS (3 or 10 µmol/kg) or vehicle once daily for 7 days before cystometry, and CYP (150 mg/kg) or saline was intraperitoneally administered 2 days before cystometry. After cystometry, the bladder tissues were collected for haematoxylin and eosin staining. In some rats, capsaicin (CAP), which can desensitise CAP-sensitive afferent nerves, was subcutaneously injected at 125 mg/kg 4 days before cystometry. CYP reduced intercontraction intervals (ICI) and bladder compliance (Comp) and increased the number of non-voiding contractions (NVCs) compared with the saline-treated control group. NaHS pretreatment dose-dependently improved the CYP-induced these changes. In bladder tissues, CYP increased histological scores of neutrophil infiltration, haemorrhage, and oedema, while NaHS had no effect on these CYP-induced changes. CAP showed a tendency to suppress CYP-induced changes in ICI. NaHS-induced improvement in CYP-induced changes in urodynamic parameters were not detected in CAP-treated rats. These findings suggest that NaHS pretreatment prevented bladder dysfunction in CYP-treated rats by suppressing CAP-sensitive bladder afferent nerves, but not by suppressing bladder inflammation. Therefore, H2S represents a new candidate as a protective drug for bladder dysfunction induced by HC, a side effect of CYP chemotherapy.

Stimulation of brain corticotropin-releasing factor receptor type1 facilitates the rat micturition via brain glutamatergic receptors.

Corticotropin-releasing factor (CRF), a representative stress-related neuropeptide, in the central nervous system reportedly both facilitates and suppresses the micturition, therefore, roles of central CRF in regulation of the micturition are still controversial. In this study, we investigated (1) effects of intracerebroventricularly (icv)-administered CRF on the micturition, and (2) brain CRF receptor subtypes (CRFR1/CRFR2) and glutamatergic receptors (NMDA/AMPA subtypes) involved in the CRF-induced effects in male Wistar rats under urethane anesthesia. Intercontraction intervals (ICI), and maximal voiding pressure (MVP), were evaluated by continuous cystometry 45 min before CRF administration or intracerebroventricular pretreatment with other drugs as follows and 3 h after CRF administration. Single-voided volume (Vv), post-voiding residual volume (Rv), bladder capacity (BC), and voiding efficiency (VE) were evaluated by single cystometry 60 min before CRF administration and 60-120 min after the administration. Icv-administered CRF reduced ICI, Vv, and BC without changing MVP, Rv, or VE. The CRF-induced ICI reduction was attenuated by icv-pretreated CP154526 (CRFR1 antagonist), MK-801 (NMDA receptor antagonist), and DNQX (AMPA receptor antagonist), but not by K41498 (CRFR2 antagonist). These results indicate that stimulation of brain CRFR1 can be involved in facilitation of the rat micturition via brain NMDA/AMPA receptors.

Protective Role of Glutathione in the Hippocampus after Brain Ischemia.

Stroke is a major cause of death worldwide, leading to serious disability. Post-ischemic injury, especially in the cerebral ischemia-prone hippocampus, is a serious problem, as it contributes to vascular dementia. Many studies have shown that in the hippocampus, ischemia/reperfusion induces neuronal death through oxidative stress and neuronal zinc (Zn2+) dyshomeostasis. Glutathione (GSH) plays an important role in protecting neurons against oxidative stress as a major intracellular antioxidant. In addition, the thiol group of GSH can function as a principal Zn2+ chelator for the maintenance of Zn2+ homeostasis in neurons. These lines of evidence suggest that neuronal GSH levels could be a key factor in post-stroke neuronal survival. In neurons, excitatory amino acid carrier 1 (EAAC1) is involved in the influx of cysteine, and intracellular cysteine is the rate-limiting substrate for the synthesis of GSH. Recently, several studies have indicated that cysteine uptake through EAAC1 suppresses ischemia-induced neuronal death via the promotion of hippocampal GSH synthesis in ischemic animal models. In this article, we aimed to review and describe the role of GSH in hippocampal neuroprotection after ischemia/reperfusion, focusing on EAAC1.

Stimulation of brain α7-nicotinic acetylcholine receptors suppresses the rat micturition through brain GABAergic receptors.

Brain nicotinic acetylcholine receptors (nAChRs) reportedly suppress the micturition, but the mechanisms responsible for this suppression remain unclear. We previously reported that intracerebroventricularly administered (±)-epibatidine (non-selective nAChR agonist) activated the sympatho-adrenomedullary system, which can affect the micturition. Therefore, we investigated (1) whether intracerebroventricularly administered (±)-epibatidine-induced effects on the micturition were dependent on the sympatho-adrenomedullary system, and (2) brain nAChR subtypes involved in the (±)-epibatidine-induced effects in urethane-anesthetized male Wistar rats. Plasma noradrenaline and adrenaline (catecholamines) were measured just before and 5 min after (±)-epibatidine administration. Evaluation of urodynamic parameters, intercontraction intervals (ICI) and maximal voiding pressure (MVP) by cystometry was started 1 h before (±)-epibatidine administration or intracerebroventricular pretreatment with other drugs and continued 1 h after (±)-epibatidine administration. Intracerebroventricularly administered (±)-epibatidine elevated plasma catecholamines and prolonged ICI without affecting MVP, and these changes were suppressed by intracerebroventricularly pretreated mecamylamine (non-selective nAChR antagonist). Acute bilateral adrenalectomy abolished the (±)-epibatidine-induced elevation of plasma catecholamines, but had no effect on the (±)-epibatidine-induced ICI prolongation. The latter was suppressed by intracerebroventricularly pretreated methyllycaconitine (selective α7-nAChR antagonist), SR95531 (GABAA antagonist), and SCH50911 (GABAB antagonist), but not by dihydro-ß-erythroidine (selective α4ß2-nAChR antagonist). Intracerebroventricularly administered PHA568487 (selective α7-nAChR agonist) prolonged ICI without affecting MVP, similar to (±)-epibatidine. These results suggest that stimulation of brain α7-nAChRs suppresses the rat micturition through brain GABAA/GABAB receptors, independently of the sympatho-adrenomedullary outflow modulation.

[The neuroprotective role of EAAC1 in hippocampal injury following ischemia-reperfusion].

Ischemic stroke is one of the most prevalent brain disorders and the major cause of long-term disability. In particularly, hippocampal injury after ischemia-reperfusion is a serious problem as it contributes to vascular dementia. Many researches have revealed that ischemia-reperfusion causes increase in reactive oxygen species production and disruption of neuronal Zn2+ homeostasis in the hippocampus, which induces hippocampal neuron death. Glutathione (GSH) is present in all mammalian cells and plays a crucial role in neuronal cell defense against oxidative stress. On the other hand, thiol group of GSH chemically chelates Zn2+ and functions as a regulator of neuronal Zn2+ homeostasis. These evidences suggest that neuronal GSH levels could be an important factor affecting neuronal surviving. The synthesis of GSH is largely influenced by intracellular cysteine availability. In neurons, excitatory amino acid carrier type 1 (EAAC1) acts as a cysteine transporter and provides cysteine substrate for GSH synthesis. Recently, several animal studies have revealed that promotion of neuronal GSH synthesis through EAAC1 reduces ischemia-induced hippocampal neuron death. This review aims to describe neuroprotective role of GSH against hippocampal injury following ischemia-reperfusion, focusing on EAAC1.

Age-related differences in responses to hydrogen sulfide in the bladder of spontaneously hypertensive rats.

OBJECTIVES: To investigate whether a response to hydrogen sulfide donors (GYY4137 and sodium hydrosulfide) and the endogenous hydrogen sulfide system (hydrogen sulfide level and expression of cysteine aminotransferase, cystathionine ß-synthase, cystathionine γ-lyase, and 3-mercaptopyruvate sulfurtransferase) in the spontaneously hypertensive rat bladder differ with age, we compared the responses of hydrogen sulfide donors to micturition and bladder relaxation, and the endogenous hydrogen sulfide system in the bladder of 18-week versus 12-week-old spontaneously hypertensive rats. METHODS: GYY4137 was intravesically administered and cystometry was performed in anesthetized rats. The responses of sodium hydrosulfide were evaluated in carbachol-mediated precontracted bladder strips. Bladder hydrogen sulfide levels and expression levels of each enzyme were investigated using the methylene blue method and Western blotting, respectively. RESULTS: GYY4137 treatment significantly prolonged intercontraction intervals only in 12-week-old rats. Sodium hydrosulfide-induced bladder relaxation was significantly attenuated in the strips of 18-week-old rats compared with that in 12-week-old rats. In the bladder dome, significant increases in hydrogen sulfide levels and in the expression of cystathionine ß-synthase, 3-mercaptopyruvate sulfurtransferase, and cysteine aminotransferase were observed in 18-week-old rats compared with 12-week-old rats. However, cystathionine γ-lyase bands were not detected in bladder tissues of either group. CONCLUSIONS: Bladder relaxation induced by hydrogen sulfide may be attenuated in spontaneously hypertensive rats in an age-dependent manner.

Therapeutic effects of losartan on prostatic hyperplasia in spontaneously hypertensive rats.

AIMS: We investigated the therapeutic effects of losartan, an angiotensin II type 1 receptor blocker, on prostatic hyperplasia in spontaneously hypertensive rats (SHRs). MAIN METHODS: Male SHRs (age, 36 weeks) were perorally treated with losartan (3 or 10 mg·kg-1) or vehicle once daily for 18 weeks. Age-matched Wistar Kyoto rats (WKYs) were used as vehicle-treated controls (n = 8). The effects of losartan were evaluated by analyzing prostate weight, blood pressure, and prostatic blood flow. The tissue malondialdehyde (MDA), interleukin-6 (IL-6), and basic fibroblast growth factor (bFGF) levels were measured. Histological analysis for the ventral prostate involved hematoxylin and eosin staining and TdT-mediated dUTP nick-end labeling (TUNEL) assay. KEY FINDINGS: Compared to the vehicle-treated WKYs, the vehicle-treated SHRs had significantly higher prostate weight, prostate weight/body weight ratio (PBR), blood pressure, glandular epithelial area, and tissue MDA, IL-6, and bFGF levels in the ventral prostate and lower prostatic blood flow. Treatment with losartan caused significant recovery of blood flow and decreased PBR and glandular epithelial area as well as tissue MDA, IL-6, and bFGF levels in the SHR ventral prostate without affecting blood pressure. High-dose losartan significantly decreased blood pressure and increased TUNEL-positive cells in the ventral prostate in SHRs. SIGNIFICANCE: Chronic losartan treatment could ameliorate prostatic hyperplasia via recovery of reduced prostatic blood flow and induction of apoptosis in the ventral prostate in SHRs. Losartan might have therapeutic effects on not only hypertension but also prostatic hyperplasia in humans.

The role of diurnal fluctuations in excitatory amino acid carrier 1 levels in post-ischemic hippocampal Zn2+ accumulation.

Accumulating evidence indicates time-of-day variations in ischemic neuronal injury. Under ischemic conditions, Zn2+ is massively released from hippocampal glutamatergic neurons, and intracellular Zn2+ accumulation results in neuron death. Notably, excitatory amino acid carrier 1 (EAAC1), known as a cysteine transporter, is involved in Zn2+ homeostasis, and its expressions exhibit a diurnal fluctuation. This study aimed to investigate whether time of day of an ischemic insult affects Zn2+ accumulation and neuronal injury and determine whether altered Zn2+ accumulation is modulated by EAAC1 diurnal fluctuation in the hippocampus in a mouse model of ischemic stroke. Mice subjected to transient global ischemia for 40 min at Zeitgeber time 18 (ZT18) (23:00) exhibited reduced Zn2+ accumulation and neuronal death in the hilar region of the hippocampus compared to those at ZT4 (09:00). The EAAC1 protein expression in the hippocampus was increased at ZT18 relative to ZT4. Intracerebroventricular injection of a non-selective excitatory amino acid transporter inhibitor, DL-threo-ß-benzyloxyaspartate, or a selective EAAC1 inhibitor, L-aspartic acid ß-hydroxamate, increased ischemia-induced Zn2+ accumulation and neuronal death in the hilus at ZT18. These findings suggest that ischemia-induced Zn2+ accumulation displays circadian fluctuations through diurnal variations in EAAC1 expressions and affects susceptibility to ischemic neuronal injury in the hippocampal hilar region.

Brain hydrogen sulfide suppresses the micturition reflex via brain GABA receptors in rats.

We recently reported that hydrogen sulfide (H2S) is a possible relaxation factor in the rat bladder. However, there is no available information about the roles of central H2S in the micturition reflex, so we investigated the effects of centrally administered GYY4137 (H2S donor) and AOAA (H2S synthesis inhibitor) on the micturition reflex in urethane-anesthetized (0.8 g/kg, ip) male Wistar rats. Cystometry was performed before and after the administration of GYY4137 (3 or 10 nmol/rat, icv) or AOAA (30 or 100 µg/rat, icv). In some rats, SR95531 (GABAA receptor antagonist, 0.1 nmol/rat, icv) or SCH50911 (GABAB receptor antagonist, 0.1 nmol/rat, icv) was administered 30 min before GYY4137 administration (10 nmol/rat, icv). Centrally administered GYY4137 dose-dependently prolonged the intercontraction intervals (ICI) without altering maximum voiding pressure (MVP). On the other hand, centrally administered AOAA dose-dependently shortened ICI without altering MVP. The AOAA (30 µg/rat, icv)-induced ICI shortening was reversed in the central presence of GYY4137 (10 nmol/rat, icv). Centrally pretreated SR95531 or SCH50911 significantly attenuated the GYY4137 (10 nmol/rat, icv)-induced prolongation of ICI, respectively. These findings suggest that endogenous brain H2S can inhibit the rat micturition reflex via both GABAA and GABAB receptors in the brain.

Protective effects of tadalafil on prostatic hyperplasia in spontaneously hypertensive rats.

We investigated the effects of the phosphodiesterase type 5 inhibitor, tadalafil on prostatic hyperplasia in a hypertensive rat model. Twelve-week-old male spontaneously hypertensive rats (SHRs) were orally treated with tadalafil (2 or 10 mg/kg/day) or vehicle for six weeks. Wistar Kyoto (WKY) rats treated with vehicle were used as controls. The effect of tadalafil was evaluated by measuring prostate weight, blood pressure, and prostatic blood flow. The presence of malondialdehyde (MDA), interleukin-6 (IL-6), transforming growth factor-beta1 (TGF-ß1), and basic fibroblast growth factor (bFGF) in the ventral prostate were examined. Hematoxylin and eosin staining was performed to assess the morphological change. The prostatic contractility was evaluated by an organ bath experiment. The vehicle-treated SHRs demonstrated a significantly higher prostate weight, prostate weight/body weight ratio (PBR), blood pressure, and tissue levels of MDA, IL-6, TGF-ß1, and bFGF, and lower prostatic blood flow compared to the vehicle-treated WKY rats. Moreover, the SHRs showed glandular morphological abnormalities in the ventral prostate compared to the WKY rats. There was no significant difference in potassium chloride or noradrenaline-induced prostatic contractility between the WKY rats and the SHRs. Treatment with tadalafil decreased prostate weight and PBR in a dose-dependent manner, and improved prostatic blood flow and tissue levels of MDA, IL-6, TGF-ß1, and bFGF in SHRs, without affecting the blood pressure. Furthermore, tadalafil ameliorated the glandular morphological abnormalities in the SHR ventral prostate. In conclusion, tadalafil could suppress the prostatic hyperplasia via recovery of reduction in prostatic blood flow in SHRs.

A novel method to align cells in a cardiac tissue-like construct fabricated by cell sheet-based tissue engineering.

Fabrication of cardiac tissue from human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) has received great interest, but a major challenge facing researchers is the alignment of cardiomyocytes in the same direction to optimize force generation. We have developed a novel method of fabricating a cardiac tissue-like construct with aligned cells based on the unidirectional stretching of an hiPS-CM sheet. A square cell sheet was harvested from a temperature-responsive culture dish and placed on a silicone surface, and an extending force was imposed on the silicone to stretch the cell sheet along one direction. To enable evaluation of cardiomyocyte morphology in vitro, a cell sheet was constructed by coculture of hiPS-CMs and human adipose-derived stem cells. In separate experiments, a stretched double-layered cell sheet constructed from hiPS-CMs alone was transplanted onto the muscle of an athymic rat, and its features were compared with those of a nonstretched (control) cell sheet. Immediately after stretching, the stretched cell sheet was significantly longer than the control cell sheet. Immunohistological analysis revealed that the cardiomyocytes showed unidirectional alignment in the stretched cell sheet but random directionality in the control cell sheet. Two weeks after transplantation, immunohistology demonstrated that the stretched cell sheet had retained the unidirectionality of its myocardial fibers and had an orientation intensity that was higher than that of the control cell sheet after transplantation or the stretched cell sheet before transplantation. Our technique provides a simple method of aligning an hiPS-CM-derived cardiac tissue-like construct without the use of a scaffold.

Effects of silodosin and tadalafil on bladder dysfunction in spontaneously hypertensive rats: Possible role of bladder blood flow.

OBJECTIVES: To investigate the effects of an alpha1-adrenoceptor antagonist, silodosin, or a phosphodiesterase type 5 inhibitor, tadalafil, on bladder overactivity in spontaneously hypertensive rats. METHODS: Twelve-week-old male spontaneously hypertensive rats were perorally administered silodosin (100 µg/kg), tadalafil (2 or 10 mg/kg) or vehicle once daily for 6 weeks. Wistar rats were used as normotensive controls and were treated with the vehicle. At 18-weeks-old, the effects of silodosin or tadalafil on blood pressure, bladder blood flow, urodynamic parameters (i.e. micturition frequency, urine output, inter-contraction interval, maximum voiding pressure, single voided volume and post-voiding residual urine volume), and bladder tissue levels of malondialdehyde, interleukin-6 and tumor necrosis factor-alpha were measured. RESULTS: A significant increase in blood pressure, micturition frequency and bladder tissue levels of malondialdehyde, interleukin-6 and tumor necrosis factor-alpha was noted in spontaneously hypertensive rats. The single voided volume, bladder capacity and bladder blood flow were significantly lower in the spontaneously hypertensive rats than in the Wistar rats. Treatment with silodosin and the higher dose of tadalafil improved the urodynamic parameters, bladder blood flow and bladder tissue levels of malondialdehyde in the spontaneously hypertensive rats without affecting the blood pressure and bladder tissue levels of interleukin-6 and tumor necrosis factor-alpha. CONCLUSIONS: Treatment with silodosin or tadalafil might improve hypertension-related bladder overactivity, as shown in spontaneously hypertensive rats through an improvement in the bladder blood flow and bladder tissue levels of oxidative stress.

[Prostatic blood flow as prominent targets on benign prostatic hyperplasia].

Benign prostatic hyperplasia/benign prostatic enlargement (BPH/BPE) is a common proliferative disease, and giving rise to associate with lower urinary tract symptoms (LUTS). However, the pathogenesis is not well clarified, and thought to be multifactorial. There are some lines of evidence that impairment in the blood supply of the lower urinary tract causes development of BPH/BPE. Clinical data showed an association between the development of BPH/BPE and atherosclerotic disease such as hypertension, diabetes and hyperlipidemia. The spontaneously hypertensive rat (SHR) has been used as model of genetic hypertension. SHR also shows decreased blood flow and hyperplastic morphological abnormalities in the ventral prostate. Our previous studies demonstrated that chronic treatment with vasodilative drugs nicorandil (ATP sensitive potassium channel opener) and silodosin (alpha1 adrenoceptor antagonist) increased blood flow and suppressed the growth factor and morphological abnormalities in the SHR ventral prostate. These data suggested that prostatic blood flow could be therapeutic targets for BPH/LUTS.

Central angiotensin II type 1 receptor as a therapeutic target against frequent urination.

AIMS: The goal of this study was to test whether central corticotropin-releasing factor (CRF) was involved in angiotensin II (Ang II) and Ang II type 1 (AT1) receptor-mediated facilitation of micturition reflex and to investigate whether peripherally administered telmisartan, AT1 receptor antagonist, suppresses the central Ang II-induced facilitation of micturition reflex in rats. METHODS: Urethane anesthetized male Wistar rats were placed under continuous cystometry before and after intracerebroventricular administration of each drug. Rats were intracerebroventricularly administered telmisartan (AT1 receptor antagonist), CP154526 (CRF1 receptor antagonist), or K41498 (CRF2 receptor antagonist) 30 minutes before intracerebroventricular administration of Ang II. Some male Wistar rats were perorally pretreated with either vehicle, AT1 receptor antagonist telmisartan or valsartan, once daily for 8 days, then measured blood pressure. Thereafter, Ang II was intracerebroventricularly administered for continuous cystometry. RESULTS: Intracerebroventricularly administered telmisartan or CP154526 dose-dependently suppressed the central Ang II-induced intercontraction interval (ICI) reduction. In contrast, intracerebroventricularly administered K41498 did not affect the central Ang II-induced response compared to vehicle pretreatment. Peripherally administered telmisartan but not valsartan suppressed the central Ang II-induced ICI reduction in rats compared to vehicle administration without altering blood pressure. CONCLUSIONS: Central Ang II induced facilitation of the micturition reflex through AT1 and CRF1 receptors. Peripherally administered telmisartan suppressed central Ang II-induced facilitation of micturition reflex.