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Adrenomedullin (AM) is a peptide involved both in the pathogenesis of cardiovascular diseases and in circulatory homeostasis. The high-affinity AM receptor is composed of receptor activity--modifying protein 2 or 3 (RAMP2 or -3) and the GPCR calcitonin receptor--like receptor. Testing our hypothesis that RAMP2 is a key determinant of the effects of AM on the vasculature, we generated and analyzed mice lacking RAMP2. Similar to AM-/- embryos, RAMP2-/- embryos died in utero at midgestation due to vascular fragility that led to severe edema and hemorrhage. Vascular ECs in RAMP2-/- embryos were severely deformed and detached from the basement membrane. In addition, the abnormally thin arterial walls of these mice had a severe disruption of their typically multilayer structure. Expression of tight junction, adherence junction, and basement membrane molecules by ECs was diminished in Ramp2-/- embryos, leading to paracellular leakage and likely contributing to the severe edema observed. In adult Ramp2+/- mice, reduced RAMP2 expression led to vascular hyperpermeability and impaired neovascularization. Conversely, ECs overexpressing RAMP2 had enhanced capillary formation, firmer tight junctions, and reduced vascular permeability. Our findings in human cells and in mice demonstrate that RAMP2 is a key determinant of the effects of AM on the vasculature and is essential for angiogenesis and vascular integrity., Introduction Many vasoactive substances play critical roles in the maintenance of cardiovascular homeostasis; moreover, imbalances among these substances have been implicated in the pathogenesis of various cardiovascular diseases. Among these, [...]

Mutations in [Na.sup.+]-HC[O.sup.-.sub.3] cotransporter (NBC-1) cause proximal renal tubular acidosis (pRTA) associated with ocular abnormalities. One pRTA patient had increased serum amylase, suggesting possible evidence of pancreatitis. To further delineate a link between NBC-1 inactivation and pancreatic dysfunction, immunohistochemical analysis was performed on rat and human pancreas using antibodies against kidney-type (kNBC-1) and pancreatic-type (pNBC-1) transporters. In rat pancreas, the anti-pNBC-1 antibody labeled acinar cells and both apical and basolateral membranes of medium and large duct cells. In human pancreas, on the other hand, the anti-pNBC-1 antibody did not label acinar cells, although it did label the basolateral membranes of the entire duct system. The labeling by anti-kNBC-1 antibody was detected in only a limited number of rat pancreatic duct cells. To examine the effects of pRTA-related mutations, R342S and R554H, on pNBC-1 function, we performed functional analysis and found that both mutants had reduced transport activities compared with the wild-type pNBC-1. These results indicate that pNBC-1 is the predominant variant that mediates basolateral HC[O.sup.-.sub.3] uptake into duct cells in both rat and human pancreas. The loss of pNBC-1 function is predicted to have significant impact on overall ductal HC[O.sup.-.sub.3] secretion, which could potentially lead to pancreatic dysfunction. [Na.sup.+]-HC[O.sup.-.sub.3] cotransporter; pRTA; pancreatic duct cells; pancreatitis

Mutations in Na[sup +]-HCO[sup -, sub 3] cotransporter (NBC-1) cause proximal renal tubular acidosis (pRTA) associated with ocular abnormalities. One pRTA patient had increased serum amylase, suggesting possible evidence of pancreatitis. To further delineate a link between NBC-1 inactivation and pancreatic dysfunction, immunohistochemicat analysis was performed on rat and human pancreas using antibodies against kidney-type (kNBC-1) and pancreatic-type (pNBC-1) transporters. In rat pancreas, the anti-pNBC-1 antibody labeled acinar cells and both apical and basolateral membranes of medium and large duct cells. In human pancreas, on the other hand, the anti-pNBC-1 antibody did not label acinar cells, although it did label the basolateral membranes of the entire duct system. The labeling by anti-kNBC-1 antibody was detected in only a limited number of rat pancreatic duct cells. To examine the effects of pRTA-related mutations, R342S and R554H, on pNBC-1 function, we performed functional analysis and found that both mutants had reduced transport activities compared with the wild-type pNBC-1. These results indicate that pNBC-1 is the predominant variant that mediates basolatera] HCO[sup -, sub 3] uptake into duct cells in both rat and human pancreas. The loss of pNBC-1 function is predicted to have significant impact on overall ducta] HCO[sup -, sub 3] secretion, which could potentially lead to pancreatic dysfunction. [ABSTRACT FROM AUTHOR]

We recently isolated a Krüppel-like zinc-finger transcription factor 5 (KLF5; also known as BTEB2 and IKLF), which is markedly induced in activated vascular smooth-muscle cells and fibroblasts. Here we describe our analysis of the in vivo function of KLF5 using heterozygous KLF5-knockout mice (Klf5+/-). In response to external stress, Klf5+/- mice showed diminished levels of arterial-wall thickening, angiogenesis, cardiac hypertrophy and interstitial fibrosis. Also, angiotensin II induced expression of KLF5, which in turn activated platelet-derived growth factor-A (PDGF-A) and transforming growth factor-β (TGF-β) expression. In addition, we determined that KLF5 interacted with the retinoic-acid receptor (RAR), that synthetic RAR ligands modulated KLF5 transcriptional activity, and that in vivo administration of RAR ligands affected stress responses in the cardiovascular system in a KLF5-dependent manner. KLF5 thus seems to be a key element linking external stress and cardiovascular remodeling. [ABSTRACT FROM AUTHOR]

AbstractBackground: α1-Adrenoceptors are highly concentrated in the urethral smooth muscles and may play an important role in the contraction of this area. However, detailed examinations of age-related changes of the properties of urethral smooth muscle have rarely been undertaken. Methods: The contractile properties of urethras from young non-parous and old parous female beagles were determined with a urethral function study, macroscopic autoradiography for urethras using [3H]-labeled tamsulosin and morphometry of the urethral muscles. Results: The antagonistic effect (pA2) of prazosin for norepinephrine was 7.76 ± 0.13 in young dogs and 7.62 ± 0.06 in aged dogs. The specific binding of [3H]-tamsulosin (a relatively selective α1A-adrenoceptor antagonist) was recognized diffusely in proximal urethras with in vitro autoradiography. The density of binding in smooth muscles was approximately 60 and 40% in circular longitudinal layers, respectively, for both dogs. Conclusions: The female canine urethra had α1A- and α1L-adrenoceptors. No age-related changes were seen in the function of the proximal urethra, distribution of α1-adrenoceptor binding sites and smooth muscle densities. [ABSTRACT FROM AUTHOR]

Studies the effects of lutenizing hormone-releasing hormone agonist treatment with or without chlormadinone acetate on patients with localized and locally advanced prostate cancer in Japan. Percentage of patients in both treatment groups who showed a complete response (CR); Improvement to CR of patients who initially exhibited a partial response to treatment after one year; Overall progression-free-survival rates.

Abstract:Background: Cancer cells often develop mechanisms to resist apoptosis and the extent of such anti-apoptotic ability has been shown to parallel tumor progression in various malignancies. Among various molecules implicated in regulating apoptosis pathway, bcl-2 and its family members are best characterized. Methods: To investigate the effect of bcl-2-mediated anti-apoptotic ability on tumor growth and progression in prostate cancer, a cell line overexpressing bcl-2 (LNCaP/bcl-2) was established by genetically engineering a prostate cancer cell line LNCaP. Tumor growth of LNCaP/bcl-2 was compared with the parental cell line in vitro and in vivo. Results: LNCaP/bcl-2 cells show resistance to apoptosis caused by nutrient deprivation and did not arrest when cultured in serum-free or androgen-free medium, while parental LNCaP cells or LNCaP cells transfected with the vector only (LNCaP/control) underwent extensive apoptosis on nutrient deprivation and sustained growth suppression in serum-free or androgen-free medium. When injected subcutaneously into nude mice, tumors deriving from LNCaP/bcl-2 cells grew faster compared with LNCaP/control for about 3 weeks (P = 0.02), but this effect was not evident after 5 weeks. Upon castration, the control tumors regressed but LNCaP/bcl-2-derived tumors showed resistance, as was previously reported. Conclusions: These data confirm the notion that anti-apoptotic function of bcl-2 is oncogenic and confers resistance to androgen deprivation and also indicate that it may also play a critical role in earlier stages of tumorigenesis. [ABSTRACT FROM AUTHOR]

Background: The effects of preoperative androgen deprivation were explored in the patients who received radical prostatectomy and subsequent adjuvant endocrine therapy for prostate cancer. Methods: Stage A2, B or C prostate cancers were randomized to one of two groups: (i) group I (n = 90), who received androgen deprivation (leuploride and chlormadinone acetate) for 3 months preoperatively followed by radical prostatectomy and adjuvant endocrine therapy (leuploride only); and (ii) group II (n = 86), who underwent the surgery followed by 3 month androgen deprivation and subsequent adjuvant endocrine therapy. The effects of preoperative androgen deprivation on clinical relapse (serum prostate specific antigen (PSA) > 1.98 ng/mL, local recurrence or distant metastasis) and PSA relapse (PSA > 0.2 ng/mL) were evaluated at 2 years after randomization. Results: There was no significant difference in clinical or PSA relapse-free survival and quality of life measures between the two groups, although relapses occurred significantly more frequently in patients who had more advanced stages, higher pretreatment PSA values or lower histologic differentiation in either group. Subgroup analysis indicated that clinical relapse-free survival in stage C cancer tended to be better in patients with preoperative androgen deprivation than in those patients without it (P < 0.1). Conclusions: Preoperative androgen deprivation may be beneficial for stage C prostate cancer patients receiving radical prostatectomy and adjuvant endocrine therapy over the 2 year observation period. A longer follow up is needed to clarify the exact extent of benefit in terms of survival and quality of life. [ABSTRACT FROM AUTHOR]