Phosphodiesterase-9 (PDE9) inhibition with BAY 73-6691 increases corpus cavernosum relaxations mediated by nitric oxide-cyclic GMP pathway in mice

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES – COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORPhosphodiesterase-9 (PDE9) specifically hydrolyzes cyclic GMP, and was detected in human corpus cavernosum. However, no previous studies explored the selective PDE9 inhibition with BAY 73-6691 in corpus cavernosum relaxations. Therefore, this study aimed to characterize the PDE9 mRNA expression in mice corpus cavernosum, and investigate the effects of BAY 73-6691 in endothelium-dependent and -independent relaxations, along with the nitrergic corpus cavernosum relaxations. Male mice received daily gavage of BAY 73-6691 (or dimethylsulfoxide) at 3 mg kg(-1) per day for 21 days. Relaxant responses to acetylcholine (ACh), nitric oxide (NO) (as acidified sodium nitrite; NaNO2 solution), sildenafil and electrical-field stimulation (EFS) were obtained in corpus cavernosum in control and BAY 73-6691-treated mice. BAY 73-6691 was also added in vitro 30 min before construction of concentration-responses and frequency curves. PDE9A and PDE5 mRNA expression was detected in the mice corpus cavernosum in a similar manner. In vitro addition of BAY 73-6691 neither itself relaxed mice corpus cavernosum nor changed the NaNO2, sildenafil and EFS-induced relaxations. However, in mice treated chronically with BAY 73-6691, the potency (pEC(50)) values for ACh, NaNO2 and sildenafil were significantly greater compared with control group. The maximal responses (E-max) to NaNO2 and sildenafil were also significantly greater in BAY 73-6691-treated mice. BAY 73-6691 treatment also significantly increased the magnitude and duration of the nitrergic corpus cavernosum relaxations (8-32 Hz). In conclusion, murine corpus cavernosum expresses PDE9 mRNA. Prolonged PDE9 inhibition with BAY 73-6691 amplifies the NO-cGMP-mediated cavernosal responses, and may be of therapeutic value for erectile dysfunction2526973FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES – COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES – COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORsem informaçãosem informaçã

Effects of neonatal capsaicin treatment in the neutrophil production, and expression of preprotachykinin-I and tachykinin receptors in the rat bone marrow

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOBone marrow is richly innervated with both myelinated and non-myelinated nerve fibers, but the role of this innervation on hemopoiesis is poorly understood. Therefore, the aim of this study was to investigate the role of C-fibers on hernatopoiesis. Wistar rats were neonatally injected with either capsaicin or its vehicle, and used at adult ages (8-10 weeks). In capsaicin-pretreated rats, the levels of substance P (SP) in bone marrow fluid were markedly reduced in comparison with the vehicle group (13.1 +/- 4.5 pg/ml versus 47.3 +/- 5.5 pg/ml, p < 0.05). In bone marrow, the number of total leukocytes was 28% higher (p < 0.05) in capsaicin-pretreated group, and this accompanied by a higher number of neutrophils, particularly of the immature forms. The mononuclear cell and eosinophils counts did not differ significantly among vehicle and capsaicin groups. In peripheral blood, the number of circulating neutrophils in the capsaicin group increased by 53.8% (p < 0.05), whereas the number of mononuclear cells did not change significantly among groups. Eosinophils were virtually absent in the circulating blood in both groups. Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) showed that both preprotachykinin (PPT)-I mRNA and the tachykinin neurokinin (NK)-1 mRNA expression in bone marrow cells significantly increased in capsaicin group, whereas the NK-2 mRNA expression was unchanged after capsaicin pretreatment. In conclusion, our data show that chronic neuropeptide depletion enhance the neutrophil proliferation and differentiation in the rat bone marrow by mechanisms involving upregulation of PPT-I gene and NK-1 receptors40717073FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOsem informaçã

Inflammatory mechanisms underlying the rat pulmonary neutrophil influx induced by airway exposure to staphylococcal enterotoxin type A

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOAssociation between staphylococcal infection and pathogenesis of upper airways disease has been reported. This study aimed to investigate the mechanisms underlying the rat pulmonary inflammation induced by airway exposure to staphylococcal enterotoxin A( SEA). 2 SEA( 0.3 - 10 ng trachea(-1)) caused dose-dependent neutrophil accumulation in BAL fluid, reaching maximal responses at 4 h ( 25-fold increase for 3 ng trachea(-1)). Significant accumulation of both lymphocytes and macrophages in BAL fluid was also observed at 4 h ( 2.1- and 1.9-fold increase, respectively, for 3 ng trachea(-1)). At later times ( 16 h), neutrophil counts in bone marrow ( immature forms) and peripheral blood increased by 63 and 81%, respectively. SEA failed to directly induce chemotaxis and adhesion of isolated neutrophils. 3 Analysis of mRNA expression for iNOS, COX-2 and CINC-2 in lung tissue showed an upregulation of these enzymes, which paralleled elevated levels of LTB4, PGE(2), TNF-alpha, IL-6 and NO2- in BAL fluid. Expression of CINC-1 was unchanged, whereas CINC-3 was reduced in SEA-treated rats. Incubation of isolated alveolar macrophages with SEA( 3 mu g ml(-1)) resulted in significant elevations of TNF-alpha and NO2- levels in the cell supernatants. 4 Dexamethasone ( 0.5 mg kg(-1)), celecoxib ( 3 mg kg(-1)) and compound 1400W ( 5 mg kg(-1)) markedly reduced SEA-induced lung neutrophil influx and NO2- levels in BAL fluid. The lipoxygenase inhibitor AA-861 ( 100 mu g kg(-1)) partly inhibited the neutrophil influx in SEA-treated rats without modifying the NO2- levels. None of these treatments reduced the number of mononuclear cells in BAL fluid ( except of dexamethasone, which abolished the increased lymphocyte counts). 5 Our study shows that airways exposure to SEA results in marked neutrophil influx through mechanisms involving increased expressions of CINC-2, iNOS and COX-2, as well as enhanced production of NO, PGE(2), LTB4, TNF-alpha and IL-61466781791FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOsem informaçã

Acute pulmonary inflammation induced by exposure of the airways to staphylococcal enterotoxin type B in rats

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOStaphylocococcus aureus is a gram-positive bacterium that produces several enterotoxins, which are responsible for most part of pathological conditions associated to staphylococcal infections, including lung inflammation. This study aimed to investigate the underlying inflammatory mechanisms involved in leukocyte recruitment in rats exposed to staphylococcal enterotoxin B (SEB). Rats were anesthetized with pentobarbital sodium and intratracheally injected with either SEB or sterile phosphate-buffered saline (PBS, 0.4 ml). Airways exposition to SEB (7.5-250 ng/trachea) caused a dose- and time-dependent neutrophil accumulation in BAL fluid, the maximal effects of which were observed at 4 h post-SEB exposure (250 ng/trachea). Eosinophils were virtually absent in BAL fluid, whereas mononuclear cell counts increased only at 24 h post-SEB. Significant elevations of granulocytes in bone marrow (mature and immature forms) and peripheral blood have also been detected. In BAL fluid, marked elevations in the levels of lipid mediators (LTB4 and PGE(2)) and cytokines (TNF-alpha, IL-6 and IL-10) were observed after SEB instillation. The SEB-induced neutrophil accumulation in BAL fluid was reduced by pretreatment with dexamethasone (0.5 mg/kg), the COX-2 inhibitor celecoxib (3 mg/kg), the selective NOS inhibitor compound 1400 W (5 mg/kg) and the lipoxygenase inhibitor AA-861 (200 mu g/kg). In separate experiments carried out with rat isolated peripheral neutrophils, SEB failed to induce neutrophil adhesion to serum-coated plates and chemotaxis. In conclusion, rat airways exposition to SEB causes a neutrophil-dependent lung inflammation at 4 h as result of the release of proinflammatory (NO, PGE(2), LTB4, TNF-alpha, IL-6) and anti-inflammatory mediators (IL-10)2171107113FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOsem informaçã

Avaliação por fotointerpretação das áreas de abrangência dos diferentes estados da erosão acelerada do solo em canaviais e pomares de citros Evaluation of areas of different states of accelerated erosion of soil in sugar cane plantations and citrus orchards utilizing photointerpretation techniques

Este estudo foi realizado com o objetivo de avaliar os estados de erosão acelerada do solo presente em áreas com canaviais e pomares de citros localizados na região administrativa de Ribeirão Preto - SP. Foram empregadas fotografias aéreas verticais, na escala aproximada de 1:40.000, do vôo da cobertura aerofotográfica da região citrícola do Estado de 1988. O estudo foi realizado identificando-se e delimitando-se todas as áreas de abrangência de cinco estados da erosão acelerada do solo presentes nos canaviais e pomares de citros. A presença da erosão acelerada severa a extremamente severa foi constatada tanto nos canaviais como nos pomares de citros, nas quatro unidades de solos de ocorrências principais na área de estudo. Os valores da extensão total das áreas de abrangência dos estados da erosão 2 a 5 (processos erosivos intensos a extremamente intensos) revelaram forte impacto sobre o desenvolvimento das culturas, degradando o solo agrícola e afetando a qualidade da água. As principais diferenças, quanto à extensão total das áreas de abrangência dos diferentes estados da erosão presente, foram identificadas principalmente entre os Argissolos e os Latossolos, e entre os dois estágios de desenvolvimento das culturas. As condições de solo exposto foram verificadas nas áreas recentemente plantadas com cana-de-açúcar ou citros, explicitando-se a grande necessidade de empregar, nessas condições, práticas conservacionistas.<br>This study was conducted with the objective of evaluating the states of accelerated erosion of soil in areas with sugar cane and citrus orchards located in Ribeirão Preto - SP, Brazil, using photointerpretation techniques. Vertical aerial photos, scale of 1:40.000 from the aerophotographic covering of the citric area of the State in 1988 have been used. The map of the land used and accelerated erosion was made in all the areas with five states of the soil accelerated erosion present in the sugar cane plantations and citrus orchards. The study showed the presence of a serious problem caused by the accelerated erosion in the sugar cane plantations and citrus orchards. The presence of areas of severe to extremely severe erosion was verified in the sugar cane plantations and in the citrus orchards, in four soil units, in the study area. The values of the total extension of the areas of the states of erosion 2 to 5 (intense to extremely intense erosive processes) revealed a strong impact of the accelerated erosion on the development of the cultures. This can cause a degradation of the agricultural land and can affect the distribution and quality of the water. The conditions of exposed soil were verified in the areas recently planted with sugar cane or citrus, and those conditions need better agricultural management