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1.
Sci Rep ; 12(1): 19008, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36347870

RESUMO

Irregular spatial distribution of photon transmission through a photochromic crystal photoisomerized by a local optical near-field excitation was previously reported, which manifested complex branching processes via the interplay of material deformation and near-field photon transfer therein. Furthermore, by combining such naturally constructed complex photon transmission with a simple photon detection protocol, Schubert polynomials, the foundation of versatile permutation operations in mathematics, have been generated. In this study, we demonstrated an order recognition algorithm inspired by Schubert calculus using optical near-field statistics via nanometre-scale photochromism. More specifically, by utilizing Schubert polynomials generated via optical near-field patterns, we showed that the order of slot machines with initially unknown reward probability was successfully recognized. We emphasized that, unlike conventional algorithms, the proposed principle does not estimate the reward probabilities but exploits the inversion relations contained in the Schubert polynomials. To quantitatively evaluate the impact of Schubert polynomials generated from an optical near-field pattern, order recognition performances were compared with uniformly distributed and spatially strongly skewed probability distributions, where the optical near-field pattern outperformed the others. We found that the number of singularities contained in Schubert polynomials and that of the given problem or considered environment exhibited a clear correspondence, indicating that superior order recognition is attained when the singularity of the given situations is presupposed. This study paves way for physical computing through the interplay of complex natural processes and mathematical insights gained by Schubert calculus.

2.
J Arrhythm ; 33(2): 130-133, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28416980

RESUMO

BACKGROUND: The pre-ejection period (PEP) and left ventricular ejection time (LVET) are easily measured by impedance cardiography (ICG). We hypothesized that the PEP/LVET measured by ICG would correlate with that measured by echocardiography, and that PEP/LVET measured by ICG would be useful for cardiac resynchronization therapy (CRT) optimization. METHODS: Newly CRT implanted patients were optimized by echocardiography. The PEP/LVET was measured by echocardiography and ICG in two different settings: optimized setting and right ventricle (RV)-only pacing. RESULTS: The PEP/LVET was significantly decreased in the optimized setting compared with that in RV-only pacing (0.62±0.13 vs 0.75±0.16, p<0.05). The PEP/LVET values calculated by ICG and echocardiography were positively correlated (r=0.553, p=0.003). CONCLUSION: ICG was useful for the optimization of CRT.

3.
Heart Vessels ; 31(9): 1446-55, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26439243

RESUMO

Both postprandial hyperlipidemia and hyperinsulinemia have been thought to play an important role in the development of atherosclerosis, and to be a potent risk factor for cardiovascular event. To examine effects of glycemic state on postprandial hyperlipidemia and hyperinsulinemia in patients with coronary artery disease (CAD), a total of 112 consecutive male pati ents with angiographically confirmed CAD were loaded with a high-fat and high-glucose test meal. CAD patients were divided into three groups as "non-diabetic", "prediabetic", and "diabetic" CAD groups. The serum triglyceride (TG) and remnant-like particle cholesterol (RLP-C) levels at the 6th hour in diabetic CAD group showed significantly higher than non-diabetic CAD group, and the incremental area under the curves (iAUCs) of these levels in diabetic CAD group were significantly greater than non-diabetic CAD group (TG, P = 0.0194; RLP-C, P = 0.0219). There were no significant differences in the iAUCs of TG or RLP-C between prediabetic and non-diabetic CAD group. The AUCs of plasma insulin levels or insulin resistance index (IRI): (AUCs of insulin) × (AUCs of glucose) as the insulin resistance marker were greater in diabetic CAD group than non-diabetic CAD group (insulin, P = 0.0373; IRI, P = 0.0228). The AUCs of serum TG or RLP-C levels showed a correlation with the AUCs of plasma insulin (AUC-TG, r = 0.5437, P < 0.0001; AUC-RLP-C, r = 0.6847, P < 0.0001), and they correlated well with the insulin resistance index (AUC-TG, r = 0.7724, P < 0.0001; AUC-RLP-C, r = 0.7645, P < 0.0001). We found that the insulin resistance showed a close relationship with postprandial hyperlipidemia in CAD patients. Diabetic, but not prediabetic state, may be a risk for postprandial impaired lipid metabolism in CAD patients.


Assuntos
Glicemia/metabolismo , Doença da Artéria Coronariana/sangue , Diabetes Mellitus Tipo 2/sangue , Hiperinsulinismo/sangue , Hiperlipidemias/sangue , Resistência à Insulina , Insulina/sangue , Lipídeos/sangue , Período Pós-Prandial , Idoso , Área Sob a Curva , Biomarcadores/sangue , Angiografia Coronária , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Hemoglobinas Glicadas/metabolismo , Humanos , Hiperinsulinismo/diagnóstico , Hiperinsulinismo/etiologia , Hiperlipidemias/diagnóstico , Hiperlipidemias/etiologia , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/diagnóstico , Curva ROC , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo
4.
J Cardiol ; 66(5): 435-44, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25840497

RESUMO

BACKGROUND: Postprandial hyperlipidemia and hyperinsulinemia have been thought to play an important role in the development of atherosclerosis. Diabetes mellitus (DM) has an impact on lipid metabolism, however, little is known about the relationship between the postprandial lipid and glucose metabolism in normoglycemic patients with coronary artery disease (CAD). METHODS: To compare the postprandial lipid and glucose metabolism in normoglycemic patients with and without CAD, a total of 36 normoglycemic patients: 19 patients with stable CAD (CAD group, age 60.2±11.3 years) and 17 patients without CAD (Non-CAD group, age 60.4±9.6 years) were loaded with a high-fat and high-glucose test meal, and the changes in serum level of the lipid and glucose parameters were monitored before and 0, 2, 4, and 6h later. RESULTS: In the Non-CAD group, postprandial serum levels of triglycerides (TG) and remnant-like particle cholesterol increased significantly and reached peak levels at the 4th hour and decreased significantly at the 6th hour of observation, whereas those levels in CAD group kept rising during 6h of observation. Although there was no significant difference in the area under the curves (AUCs) for the postprandial plasma glucose levels between CAD and Non-CAD group, the AUCs for the postprandial plasma insulin and C-peptide levels were significantly higher in the CAD group than in the Non-CAD group. The AUCs for postprandial TG levels showed good correlation with those for postprandial plasma insulin and C-peptide levels (insulin: r=0.455, p<0.005; C-peptide: r=0.462, p<0.05). CONCLUSIONS: These findings suggest that postprandial hyperlipidemia and hyperinsulinemia may have a close relationship in CAD patients without DM and might play an important role in the development of atherosclerosis even before the onset of diabetes.


Assuntos
Glicemia/análise , Doença da Artéria Coronariana/metabolismo , Resistência à Insulina , Lipídeos/sangue , Período Pós-Prandial , Idoso , Área Sob a Curva , Aterosclerose/etiologia , Peptídeo C/sangue , Colesterol/sangue , Doença da Artéria Coronariana/complicações , Dieta Hiperlipídica , Feminino , Glucose/administração & dosagem , Humanos , Hiperinsulinismo/etiologia , Hiperlipidemias/etiologia , Insulina/sangue , Metabolismo dos Lipídeos , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Edulcorantes/administração & dosagem , Fatores de Tempo , Triglicerídeos/sangue
5.
Cardiovasc Interv Ther ; 30(3): 293-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25103637

RESUMO

A 65-year-old man with occlusion of the left superficial femoral artery (SFA) underwent the endovascular therapy (EVT). A successful EVT was performed with three paclitaxel-eluting peripheral stents (Zilver PTX®) implanted in the left SFA. Angiography 1 year later showed an exudation of contrast outside the stent struts, and intravascular ultrasound, and optical coherence tomography also showed incomplete stent apposition with remarkable positive vascular remodeling. Zilver PTX® stent is a polymer-free stent and it is unclear that the reason why the patient treated with Zilver PTX® stents in the SFA lesions caused the contrast stainings outside the stents. However, we need more careful long-term follow-up of this patient for late thrombosis.


Assuntos
Stents Farmacológicos , Artéria Femoral/cirurgia , Idoso , Angiografia , Artéria Femoral/diagnóstico por imagem , Humanos , Masculino , Paclitaxel/administração & dosagem , Tomografia de Coerência Óptica , Ultrassonografia de Intervenção , Remodelação Vascular
6.
Cardiovasc Interv Ther ; 30(4): 362-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25319810

RESUMO

A 68-year-old female was presented with claudication in the left lower leg. She underwent angiography with carbon dioxide (CO2) because she had a history of anaphylactic shock to iodinated contrast medium. It revealed total occlusion of the left superficial femoral artery (SFA), and subsequently endovascular therapy (EVT) was performed by an antegrade approach from the left common femoral artery. After stent implantation, we performed optical frequency domain imaging (OFDI) using CO2 as contrast medium. OFDI has been extensively studied in the coronary circulation; however, its use in the peripheral arterial circulation is scarce. We present a case of stent implantation and OFDI using CO2 as an ancillary tool during EVT for SFA lesions in the patient with contraindication to iodinated contrast medium.


Assuntos
Angiografia/métodos , Arteriopatias Oclusivas/cirurgia , Implante de Prótese Vascular/métodos , Dióxido de Carbono , Artéria Femoral , Stents , Cirurgia Assistida por Computador/métodos , Idoso , Arteriopatias Oclusivas/diagnóstico , Doença Crônica , Feminino , Humanos
7.
PLoS One ; 9(11): e110446, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25365359

RESUMO

BACKGROUND: Metabolic disorders, caused by excessive calorie intake and low physical activity, are important cardiovascular risk factors. Rho-kinase, an effector protein of the small GTP-binding protein RhoA, is an important cardiovascular therapeutic target and its activity is increased in patients with metabolic syndrome. We aimed to examine whether Rho-kinase inhibition improves high-fat diet (HFD)-induced metabolic disorders, and if so, to elucidate the involvement of AMP-activated kinase (AMPK), a key molecule of metabolic conditions. METHODS AND RESULTS: Mice were fed a high-fat diet, which induced metabolic phenotypes, such as obesity, hypercholesterolemia and glucose intolerance. These phenotypes are suppressed by treatment with selective Rho-kinase inhibitor, associated with increased whole body O2 consumption and AMPK activation in the skeletal muscle and liver. Moreover, Rho-kinase inhibition increased mRNA expression of the molecules linked to fatty acid oxidation, mitochondrial energy production and glucose metabolism, all of which are known as targets of AMPK in those tissues. In systemic overexpression of dominant-negative Rho-kinase mice, body weight, serum lipid levels and glucose metabolism were improved compared with littermate control mice. Furthermore, in AMPKα2-deficient mice, the beneficial effects of fasudil, a Rho-kinase inhibitor, on body weight, hypercholesterolemia, mRNA expression of the AMPK targets and increase of whole body O2 consumption were absent, whereas glucose metabolism was restored by fasudil to the level in wild-type mice. In cultured mouse myocytes, pharmacological and genetic inhibition of Rho-kinase increased AMPK activity through liver kinase b1 (LKB1), with up-regulation of its targets, which effects were abolished by an AMPK inhibitor, compound C. CONCLUSIONS: These results indicate that Rho-kinase inhibition ameliorates metabolic disorders through activation of the LKB1/AMPK pathway, suggesting that Rho-kinase is also a novel therapeutic target of metabolic disorders.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Doenças Metabólicas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Quinases Associadas a rho/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/deficiência , Proteínas Quinases Ativadas por AMP/genética , Animais , Linhagem Celular , Dieta Hiperlipídica , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Expressão Gênica , Masculino , Doenças Metabólicas/genética , Camundongos , Camundongos Knockout , Modelos Biológicos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Fenótipo , Proteínas Serina-Treonina Quinases/metabolismo , Quinases Associadas a rho/genética
8.
Circ J ; 78(6): 1465-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24705390

RESUMO

BACKGROUND: Pulmonary hypertension (PH) causes elevated right ventricular (RV) systolic pressure, RV remodeling and finally RV failure to death. However, the mechanisms of RV remodeling in PH remain to be fully elucidated. METHODS AND RESULTS: RV autopsy samples from 6 PH patients with RV failure against 3 age- and sex-matched controls were first examined. Next, RV remodeling in 2 mouse models of chronic hypoxia-induced PH with endothelial nitric oxide synthase-deficient (eNOS(-/-)) and collagenase-resistant knock-in (Col(R/R)) mice were examined. In humans, RV failure was associated with RV hypertrophy, interstitial and perivascular fibrosis, decreased RV capillary density and increased macrophage recruitment. Furthermore, immunostaining showed that perivascular matrix metalloproteinase-2 was increased in PH patients with RV failure. In animals, both hypoxic eNOS(-/-) and Col(R/R) mice developed a greater extent of RV hypertrophy, perivascular remodeling and macrophage infiltration compared with wild-type mice. Capillary rarefaction was developed in hypoxic eNOS(-/-) mice, while Col(R/R) mice were able to increase their capillary density in the RV in response to chronic hypoxia. Both mouse models showed increased autophagy even under normoxic condition. CONCLUSIONS: These results indicate that RV remodeling occurs early during PH development through fibrosis, perivascular remodeling, capillary rarefaction and autophagy, in which the eNOS pathway and collagen metabolism might be involved.


Assuntos
Colágeno/metabolismo , Hipertensão Pulmonar/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Remodelação Ventricular , Adulto , Animais , Autofagia/genética , Colágeno/genética , Feminino , Fibrose , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo III/genética
9.
Cardiovasc Interv Ther ; 29(2): 187-92, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24214731

RESUMO

A 61-year-old man with in-stent occlusion of the superficial femoral artery (SFA) underwent the endovascular therapy using a subintimal technique. The wire was intentionally advanced into the subintimal space next to the occluded stent in the SFA, and a stent was implanted in a double barrel fashion outside of the in-stent occlusion site. The procedure was performed without any complications and with the successful angiographic and intravascular ultrasound imaging results. At 1-year follow-up, the patient still had no leg complaints and the stent was still shown as patent. The procedure might be a useful technique when the recanalization was proved impossible after several attempts to recanalize the primary occluded stent in the SFA.


Assuntos
Angioplastia com Balão , Arteriopatias Oclusivas/terapia , Artéria Femoral , Stents , Angioplastia com Balão/métodos , Arteriopatias Oclusivas/diagnóstico por imagem , Artéria Femoral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Recidiva , Resultado do Tratamento , Grau de Desobstrução Vascular
10.
Cardiovasc Interv Ther ; 29(2): 151-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23918078

RESUMO

A 67-year-old man with recent myocardial infarction underwent a total of five sirolimus-eluting stents (SES) implantation for three vessels stage by stage. A follow-up angiography showed no significant restenosis except one in the side branch. Thereafter, he had remained asymptomatic. Sixty-six months later, he had an acute myocardial infarction with cardiogenic shock due to simultaneous 3-vessel very late stent thrombosis (VLST). After successful percutaneous coronary intervention, final angiography revealed serious peri-stent contrast staining along with positive remodeling and grade V stent fracture. This rare case illustrates simultaneous 3-vessel VLST, associating with multiple SES-related problems, under continuation of aspirin and cilostazol.


Assuntos
Angioplastia Coronária com Balão , Reestenose Coronária/terapia , Stents Farmacológicos/efeitos adversos , Imunossupressores/administração & dosagem , Infarto do Miocárdio/terapia , Sirolimo/administração & dosagem , Idoso , Reestenose Coronária/diagnóstico por imagem , Humanos , Masculino , Infarto do Miocárdio/complicações , Inibidores da Agregação Plaquetária/administração & dosagem , Radiografia , Recidiva , Choque Cardiogênico/terapia , Fatores de Tempo , Resultado do Tratamento
11.
Tohoku J Exp Med ; 228(4): 305-15, 2012 12.
Artigo em Inglês | MEDLINE | ID: mdl-23124103

RESUMO

Many studies have aimed to identify anti-atherogenic agents in cardiovascular medicine. We have recently demonstrated that the combination therapy with olmesartan (OLM), an angiotensin II receptor blocker, and azelnidipine (AZL), a dihydroprydine calcium-channel blocker, improves endothelial function in diabetic Apolipoprotein-deficient (ApoE(-/-)) mice. In the present study, we examined whether this combination therapy also inhibits atherosclerosis in mice. We used male control and streptozocin-induced diabetic ApoE(-/-) mice. Diabetic ApoE(-/-) mice were orally treated for 5 weeks with vehicle (Untreated), OLM (30 mg/kg/day), AZL (10 mg/kg/day), their combination (OLM+AZL), or hydralazine (HYD, 5 mg/kg/day) as an antihypertensive control. At 5 weeks, systolic blood pressure was significantly elevated in Untreated but was normalized in OLM+AZL and HYD. The atherosclerosis area in the thoracic aorta, perivascular fibrosis and medial thickness of the coronary arteries were increased in Untreated and were ameliorated in OLM+AZL but not in HYD. Staining with a fluorescent probe dihydroethidium showed that production of reactive oxygen species was increased in Untreated, and ameliorated in OLM+AZL. Consistent with these findings, macrophage infiltration in the kidney and the expression of receptor for advanced glycation end-products in the heart, kidney and liver were increased in Untreated and were all ameliorated in OLM+AZL, associated with up-regulation of endothelial NO syntheses (eNOS). In conclusion, the combination therapy with OLM and AZL exerts anti-atherogenic effect in diabetic ApoE(-/-) mice through suppression of oxidative stress and activation of eNOS, independent of its blood pressure-lowering effects. Clinically, this combination therapy may be useful for patients with hypertension, hyperlipidemia and diabetes.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/complicações , Aterosclerose/tratamento farmacológico , Ácido Azetidinocarboxílico/análogos & derivados , Diabetes Mellitus Experimental/complicações , Di-Hidropiridinas/uso terapêutico , Imidazóis/uso terapêutico , Tetrazóis/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Apolipoproteínas E/metabolismo , Aterosclerose/patologia , Aterosclerose/fisiopatologia , Ácido Azetidinocarboxílico/farmacologia , Ácido Azetidinocarboxílico/uso terapêutico , Compostos Azo/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Di-Hidropiridinas/farmacologia , Quimioterapia Combinada , Imidazóis/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Sístole/efeitos dos fármacos , Tetrazóis/farmacologia
12.
Circ Res ; 111(1): 87-96, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-22550140

RESUMO

RATIONALE: We have previously demonstrated that the importance of endothelium-derived hyperpolarizing factor (EDHF) increases as the vessel size decreases and that endothelium-derived hydrogen peroxide (H(2)O(2)) is an EDHF in animals and humans, for which endothelial nitric oxide synthase (eNOS) is the major source. Recent studies have suggested the important role of the bone marrow (BM) in modulating cardiovascular and metabolic functions. OBJECTIVE: We aimed to examine whether BM plays a role in modulating microvascular endothelial and metabolic functions in mice, and if so, to elucidate the mechanisms involved. METHODS AND RESULTS: Male eNOS(-/-) mice were transplanted with BM cells from wild-type (WT) or eNOS(-/-) mice and were maintained for 6 weeks. Endothelium-dependent relaxations and hyperpolarizations of mesenteric arteries to acetylcholine were reduced in eNOS(-/-) mice and were markedly improved when transplanted with WT-BM but not with eNOS(-/-)-BM. The enhanced component of endothelium-dependent relaxations was abolished by catalase, indicating that the improved responses were mediated by H(2)O(2). In contrast, no such beneficial effect was noted in the aorta. Reduced plasma adiponectin levels and impaired glucose tolerance in eNOS(-/-) mice were also improved by WT-BM transplantation. Neuronal nitric oxide synthase (nNOS) in mesenteric arteries of eNOS(-/-) mice was significantly upregulated only when transplanted with WT-BM. Importantly, the beneficial effects of WT-BM transplantation were absent in eNOS(-/-)/adiponectin(-/-) or eNOS(-/-)/nNOS(-/-) mice. CONCLUSIONS: These results provide the first evidence that BM plays an important role in modulating microvascular endothelial and metabolic functions, for which adiponectin and nNOS may be involved.


Assuntos
Adiponectina/metabolismo , Medula Óssea/metabolismo , Microambiente Celular , Endotélio Vascular/metabolismo , Artérias Mesentéricas/metabolismo , Microvasos/metabolismo , Vasodilatação , Adiponectina/genética , Animais , Antioxidantes/farmacologia , Aorta/metabolismo , Fatores Biológicos/metabolismo , Pressão Sanguínea , Peso Corporal , Transplante de Medula Óssea , Relação Dose-Resposta a Droga , Dislipidemias/genética , Dislipidemias/metabolismo , Dislipidemias/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Citometria de Fluxo , Intolerância à Glucose/genética , Intolerância à Glucose/metabolismo , Intolerância à Glucose/fisiopatologia , Teste de Tolerância a Glucose , Peróxido de Hidrogênio/metabolismo , Imuno-Histoquímica , Lipídeos/sangue , Masculino , Potenciais da Membrana , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/patologia , Artérias Mesentéricas/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/efeitos dos fármacos , Microvasos/patologia , Microvasos/fisiopatologia , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Fatores de Tempo , Quimeras de Transplante , Vasodilatadores/farmacologia
13.
Circ J ; 76(7): 1768-79, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22466633

RESUMO

BACKGROUND: Endothelium-derived relaxing factors play an important role in cardiovascular homeostasis. Among them, endothelium-derived hyperpolarizing factor (EDHF) is important especially in microcirculation. It has previously been demonstrated that endothelium-derived hydrogen peroxide (H(2)O(2)) is an EDHF in animals and humans and that endothelial nitric oxide synthase (eNOS) plays diverse roles as a nitric oxide (NO) generating system in conduit arteries and as an EDHF/H(2)O(2) generating system in microvessels. As compared with NO-mediated responses, those by EDHF are resistant to atherosclerosis, contributing to the maintenance of cardiovascular homeostasis. The aim of this study is to elucidate the molecular mechanisms for enhanced EDHF-mediated responses in microvessels. METHODS AND RESULTS: This study used male wild-type mice and caveolin-1-deficient mice (caveolin-1(-/-) mice). In the endothelium, eNOS was functionally suppressed in mesenteric arteries (microvessels) compared with the aorta (conduit arteries), for which Ca(2+)/calmodulin-dependent protein kinase kinase ß (CaMKKß) and caveolin-1 are involved, as EDHF-mediated responses were inhibited by STO-609 (an inhibitor of CaMKKß) and in caveolin-1(-/-) mice, respectively. In vascular smooth muscle, relaxation responses to H(2)O(2) were enhanced through a protein kinase G1α (PKG1α)-mediated mechanism in mesenteric arteries compared with the aorta, as they were inhibited by Rp-8-Br-cGMPS (an inhibitor of PKG1α). CONCLUSIONS: These results indicate that CaMKKß, caveolin-1, and PKG1α are substantially involved in the mechanisms for the enhanced EDHF-mediated responses in microvessels in mice.


Assuntos
Fatores Biológicos/metabolismo , Endotélio Vascular/metabolismo , Mesentério/irrigação sanguínea , Músculo Liso Vascular/metabolismo , Vasodilatação , Animais , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Caveolina 1/deficiência , Caveolina 1/genética , Proteína Quinase Dependente de GMP Cíclico Tipo I , Proteínas Quinases Dependentes de GMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
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