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1.
J Eur Acad Dermatol Venereol ; 37(12): 2526-2536, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37478291

RESUMO

BACKGROUND: The effectiveness of moisturizers in preventing infant atopic dermatitis (AD) remains unclear. We previously showed that using 2e moisturizer of commercial moisturizer (Shiseido Japan Co., Ltd.) at least once a day significantly prevented AD in infants as compared with as-needed petroleum jelly. This trial aimed to determine the effectiveness of twice- or once-daily application of Fam's Baby moisturizer (Fam's Inc.) in preventing AD compared with once-daily 2e moisturizer. METHODS: This trial was a single-centre, three-parallel-group, assessor-blinded, superiority, individually randomized, controlled, phase II trial that was conducted from 25 August 2020 to 28 September 2021. We randomly assigned 60 newborns with at least one parent or sibling who has AD to receive Fam's Baby moisturizer twice daily (Group A) or once daily (Group B), or 2e once daily (Group C) in a 1:1:1 ratio until they were 32 weeks old. The primary outcome was the time of AD onset. RESULTS: Atopic dermatitis was observed in 11/20 (55%), 5/20 (25%) and 10/20 (50%), infants in Groups A, B and C, respectively. Cumulative incidence values for AD according to the Kaplan-Meier method showed that infants in Group B tended to maintain an intact skin for a longer period than those in Group C (median time, not reached [NR] vs. 212 days, log-rank test, p = 0.064). Cox regression analysis showed that the risk of AD tended to be lower in Group B (hazard ratio with group C as control, 0.36; 95% confidential intervals: 0.12-1.06). No serious adverse events occurred in any of the enrolled infants. CONCLUSION: Fam's Baby moisturizer may better prevent AD than 2e. Further large-scale trials should be performed to confirm the efficacy of Fam's Baby moisturizer in preventing AD in infants.


Assuntos
Dermatite Atópica , Humanos , Recém-Nascido , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/prevenção & controle , Emolientes/uso terapêutico , Incidência , Vaselina , Resultado do Tratamento
2.
J Microsc ; 231(3): 455-65, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18755001

RESUMO

In response to chemoattractants, migrating cells form protrusions, such as lamellipodia and filopodia, and structures, such as ruffles over lamellipodia, focal complexes and focal adhesions at leading edges. The formation of these leading edge structures is essential for directional cell movement. Nectin-like molecule-5 (Necl-5) interacts in cis with PDGF receptor and integrin alpha(v)beta(3), and enhances the activation of signalling molecules associated with these transmembrane proteins, which results in the formation of leading edge structures and enhancement of directional cell movement. When migrating cells come into contact with each other, cell-cell adhesion is initiated, resulting in reduced cell velocity. Necl-5 first interacts in trans with nectin-3. This interaction is transient and induces down-regulation of Necl-5 expression at the cell surface, resulting in reduced cell movement. Cell proliferation is also suppressed by the down-regulation of Necl-5, because the inhibitory effect of Necl-5 on Sprouty2, a negative regulator of the Ras signalling, is diminished. PDGF receptor and integrin alpha(v)beta(3), which have interacted with Necl-5, then form a complex with nectin, which initiates cell-cell adhesion and recruits cadherin to the nectin-based cell-cell adhesion sites to form stable adherens junctions. The formation of adherens junctions stops cell movement, in part through inactivation of integrin alpha(v)beta(3) caused by the trans-interaction of nectin. Thus, nectin and Necl-5 play key roles in the regulation of cell movement and proliferation.


Assuntos
Moléculas de Adesão Celular/metabolismo , Fenômenos Fisiológicos Celulares , Proliferação de Células , Glicoproteínas/metabolismo , Locomoção , Animais , Proteínas de Membrana , Modelos Biológicos , Nectinas , Ratos
3.
Oncogene ; 25(1): 8-19, 2006 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-16170364

RESUMO

Cadherin first forms homo-cis-dimers on the cell surface of the same cells, followed by formation of homo-trans-dimers (trans-interactions) in a Ca2+-dependent manner, eventually causing adherens junctions. In addition, trans-interacting cadherin induces activation of Rac small G protein, which stabilizes non-trans-interacting cadherin on the plasma membrane by inhibiting its endocytosis through the reorganization of the actin cytoskeleton. However, it has not fully been understood how cadherin induces the activation of Rac. We examined here the molecular mechanism of the activation of Rac by trans-interacting cadherin in fibroblasts and epithelial cells. Trans-interacting cadherin induced activation of c-Src locally at the cadherin-based cell-cell adhesion sites. c-Src then tyrosine-phosphorylated Vav2, one of the Rac-GDP/GTP exchange factors (GEFs), and induced activation of C3G, one of the Rap1-GEFs, through Crk adaptor protein, resulting in the activation of Rap1 locally at the cadherin-based cell-cell adhesion sites. The c-Src-catalysed tyrosine phosphorylation was not sufficient for the activation of Vav2 and the c-Src-induced activation of Rap1 was additionally necessary for it, although activated Rap1 alone was not sufficient for the activation of non-tyrosine-phosphorylated Vav2. This effect of Rap1 on Vav2 was mediated by phosphatidylinositol 3-kinase. We describe here the signaling pathway from trans-interacting cadherin to the activation of Rac.


Assuntos
Caderinas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-vav/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rap1 de Ligação ao GTP/metabolismo , Actinas/química , Actinas/metabolismo , Adenoviridae/genética , Androstadienos/farmacologia , Animais , Cálcio/metabolismo , Adesão Celular , Linhagem Celular , Membrana Celular/metabolismo , Citoesqueleto/metabolismo , DNA/metabolismo , Dimerização , Cães , Endocitose , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Células Epiteliais/citologia , Fibroblastos/metabolismo , Fator 2 de Liberação do Nucleotídeo Guanina/metabolismo , Imunoprecipitação , Camundongos , Microscopia de Fluorescência , Modelos Genéticos , Fosforilação , Plasmídeos/metabolismo , Proteínas Proto-Oncogênicas c-crk/metabolismo , Transdução de Sinais , Fatores de Tempo , Ativação Transcricional , Transfecção , Tirosina/química , Tirosina/metabolismo , Wortmanina
4.
Circ Res ; 88(2): 175-80, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11157669

RESUMO

Although ischemic stress, including ischemic preconditioning (IP), activates p38 mitogen-activated protein kinase (MAPK), the relationship between p38 MAPK activation and the underlying cellular mechanisms of cardioprotection by IP is not verified in vivo. We examined the effects of the selective p38 MAPK inhibition on the cardioprotective effect of IP in the open-chest dogs. The coronary artery was occluded 4 times for 5 minutes, separated by 5 minutes of reperfusion (IP) followed by 90 minutes of occlusion and 6 hours of reperfusion. We infused SB203580 into the coronary artery during IP and 1 hour of reperfusion, during IP alone, and during sustained ischemia in the IP group. p38 MAPK activity markedly increased during IP but did not additionally increase at the onset of ischemia and was even attenuated at 15 minutes of sustained ischemia, and heat-shock protein (HSP) 27 was phosphorylated and translocated from cytosol to myofibril or nucleus without affecting total protein level at the onset of ischemia compared with the control group. SB203580 treatment (1 micromol/L) only during IP blunted the infarct size limitation by IP (37.3+/-6.3% versus 7.4+/-2.1% in the IP group, P:<0.01) and attenuated either phosphorylation or translocation of HSP27 during IP. Although the SB203580 treatment throughout the preischemic and postischemic periods had no significant effect on infarct size (33.3+/-9.4%) in this model, treatment with SB203580 only during ischemia partially mimicked the infarct size limitation by IP (26.8+/-3.5%). Thus, transient p38 MAPK activation during ischemic preconditioning mainly mediates the cardioprotection followed by HSP27 phosphorylation and translocation in vivo in the canine heart.


Assuntos
Precondicionamento Isquêmico Miocárdico , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Infarto do Miocárdio/enzimologia , Miocárdio/enzimologia , Animais , Western Blotting , Circulação Coronária/fisiologia , Modelos Animais de Doenças , Cães , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Coração/efeitos dos fármacos , Proteínas de Choque Térmico/efeitos dos fármacos , Proteínas de Choque Térmico/metabolismo , Hemodinâmica/efeitos dos fármacos , Imidazóis/administração & dosagem , Infusões Intravenosas , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Infarto do Miocárdio/patologia , Fosforilação/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Piridinas/administração & dosagem , Taxa de Sobrevida , Proteínas Quinases p38 Ativadas por Mitógeno
5.
Circulation ; 104(6): 705-10, 2001 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-11489779

RESUMO

BACKGROUND: Phosphodiesterase III inhibitors (PDEIII-Is) improve the hemodynamic status of heart failure via inotropic/vasodilatory effects attributable to the increase in intracellular cAMP level. Direct cardioprotection by PDEIII-Is and its underlying mechanisms, however, have not been identified. We tested the infarct size-limiting effect of PDEIII-Is and the roles of cAMP, protein kinase (PK) A, PKC, and mitogen-activated protein kinase (MAPK) families in open-chest dogs. Methods and Results-- Milrinone, olprinone (PDEIII-Is), or dibutyryl-cAMP (db-cAMP) was injected intravenously 30 minutes before 90-minute ischemia, followed by 6 hours of reperfusion. Olprinone was also examined with an intracoronary cotreatment with a PKA inhibitor (H89), a PKC inhibitor (GF109203X), an extracellular signal-regulated kinase kinase (MEK) inhibitor (PD98059), or a p38 MAPK inhibitor (SB203580) throughout the preischemic period. Either PDEIII-Is or db-cAMP caused substantial hemodynamic changes, which returned to control levels in 30 minutes. Collateral flow and percent risk area were identical for all groups. Both PDEIII-Is and db-cAMP increased myocardial p38 MAPK activity during the preischemic period, which was blocked by H89, but not by GF109203X. Both PDEIII-Is and db-cAMP reduced infarct size (19.1+/-4.1%, 17.5+/-3.3%, and 20.3+/-4.8%, respectively, versus 36.1+/-6.2% control, P<0.05 each). Furthermore, the effect of olprinone was blunted by either H89 (35.5+/-6.4%) or SB203580 (32.6+/-5.9%), but not by GF109203X or PD98059. H89, GF109203X, PD98059, or SB203580 alone did not influence infarct size. CONCLUSIONS: Pretreatment with PDEIII-Is has cardioprotective effects via cAMP-, PKA-, and p38 MAPK-dependent but PKC-independent mechanisms in canine hearts.


Assuntos
Fármacos Cardiovasculares/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Sulfonamidas , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Bucladesina/farmacologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Cães , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Hemodinâmica/efeitos dos fármacos , Imidazóis/farmacologia , Indóis/farmacologia , Isoquinolinas/farmacologia , Maleimidas/farmacologia , Milrinona/farmacologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/prevenção & controle , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Piridinas/farmacologia , Piridonas/farmacologia , Fibrilação Ventricular/patologia , Fibrilação Ventricular/fisiopatologia , Fibrilação Ventricular/prevenção & controle , Proteínas Quinases p38 Ativadas por Mitógeno
6.
J Am Coll Cardiol ; 35(2): 405-13, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10676688

RESUMO

OBJECTIVES: We sought to prospectively determine whether patients with congestive heart failure (CHF) at risk for paroxysmal atrial fibrillation (PAF) could be identified by clinical and study variables including the P-wave signal-averaged electrocardiogram (P-SAECG). BACKGROUND: Although it is important to assess the risk of developing PAF in patients with CHF, it still remains difficult to predict the PAF appearance in patients with CHF clinically. METHODS: The study group consisted of 75 patients in sinus rhythm without a history of PAF, whose left ventricular ejection fraction, as measured by radionuclide angiography, was <40%. These patients underwent P-SAECG, echocardiography and 24-h Holter monitoring; in addition, the plasma concentration of atrial natriuretic peptide (ANP) was measured at study entry. RESULTS: An abnormal P-SAECG was found at study entry in 29 of 75 patients. In the follow-up period of 21 +/- 9 months, the PAF attacks documented on the ECG significantly more frequently occurred in patients with (32%) rather than without an abnormal P-SAECG (2%) (p = 0.0002). The plasma ANP level was significantly higher in patients with rather than without PAF attacks (75 +/- 41 vs. 54 +/- 60 pg/ml, p = 0.01), although there were no significant differences in age, left atrial dimension or high grade atrial premature beats between the groups. The multivariate Cox analysis identified that the variables significantly associated with PAF development were an abnormal P-SAECG (hazard ratio 19.1, p = 0.0069) and elevated ANP level > or =60 pg/ml (hazard ratio 8.6, p = 0.018). CONCLUSIONS: An abnormal P-SAECG and elevated ANP level could be predictors of PAF development in patients with CHF.


Assuntos
Fibrilação Atrial/diagnóstico , Insuficiência Cardíaca/complicações , Taquicardia Paroxística/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/sangue , Fibrilação Atrial/etiologia , Fator Natriurético Atrial/sangue , Cromatografia Líquida de Alta Pressão , Ecocardiografia , Eletrocardiografia Ambulatorial , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Ventriculografia com Radionuclídeos , Volume Sistólico , Taquicardia Paroxística/sangue , Taquicardia Paroxística/etiologia
7.
Heart ; 79(3): 256-61, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9602659

RESUMO

OBJECTIVE: To determine whether the effectiveness of long-term beta blocker treatment for idiopathic dilated cardiomyopathy can be predicted by signal averaged electrocardiography (ECG). PATIENTS: 31 patients with dilated cardiomyopathy and without bundle branch block were included in a retrospective study and 16 in a prospective study. METHODS: A signal averaged ECG was recorded before beta blocker treatment, and three variables were measured from the vector magnitude: QRS duration, root mean square voltage for the last 40 ms (RMS40), and duration of the terminal low amplitude signals (< 40 microV) (LAS40). In the retrospective study, these variables were compared among good responders (showing > or = 0.10 increase in ejection fraction 12 months after start of beta blocker treatment) and poor responders without such improvement. The validity of the signal averaged ECG criteria for prediction of the response to beta blocker treatment was examined in the prospective study. RESULTS: In the retrospective study, good responders (n = 16) had a shorter QRS duration (mean (SD): 122.9 (11) v 138 (14.4) ms, p < 0.005) and LAS40 (33.1 (8.9) v 42.5 (7.8) ms, p < 0.005), and a higher RMS40 (31.6 (16.3) v 19.0 (10.3) microV, p < 0.02) than poor responders (n = 15). Signal averaged ECG criteria for good response were defined as two or more of the following: QRS duration < 130 ms, RMS40 > 20 microV, LAS40 < 40 ms (sensitivity 81%, specificity 73%). In the prospective study, six of seven patients who met these criteria showed a good response to the beta blocker treatment, while eight of nine who did not showed a poor response (chi 2 = 6.1, p < 0.02). The signal averaged ECG criteria gave a sensitivity of 86% and a specificity of 89% for predicting the effectiveness of beta blocker treatment. CONCLUSIONS: A signal averaged ECG might be useful in predicting the effectiveness of beta blocker treatment for dilated cardiomyopathy.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Cardiomiopatia Dilatada/tratamento farmacológico , Eletrocardiografia , Metoprolol/uso terapêutico , Processamento de Sinais Assistido por Computador , Cardiomiopatia Dilatada/fisiopatologia , Feminino , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento
8.
Bioorg Med Chem Lett ; 11(4): 549-51, 2001 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-11229768

RESUMO

A series of diarylamide derivatives were synthesized and evaluated for their inhibitory activities against human coronary artery smooth muscle cells (SMCs) and human coronary artery endothelial cells (ECs). Compound 2w was superior to the lead compound, Tranilast, in terms of the potency of the activity and cell selectivity.


Assuntos
Amidas/síntese química , Vasos Coronários/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Amidas/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Doença das Coronárias/tratamento farmacológico , Vasos Coronários/citologia , Músculo Liso Vascular/citologia , Relação Estrutura-Atividade
9.
Eur Heart J ; 20(3): 211-20, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10082154

RESUMO

AIMS: This study sought to investigate whether the spatial dispersion of signal-averaged P wave duration would be increased in patients with paroxysmal atrial fibrillation, by use of precordial mapping of the P wave signal-averaged ECG. METHODS AND RESULTS: The P wave signal-averaged ECG was recorded by the P wave-triggering method from 16 precordial leads in 55 patients with paroxysmal atrial fibrillation and 57 control subjects. As an index of the dispersion of signal-averaged P wave duration, we obtained the difference between the maximum and minimum in 16 recording sites. The dispersion was significantly greater in the patients with paroxysmal atrial fibrillation than the controls (26.6 +/- 9.5 vs 14.8 +/- 6.7 ms, P<0.0001). In 25 patients with symptomatic attacks of paroxysmal atrial fibrillation, the signal-averaged ECG was repeated 1 h after a single dose of orally administered pilsicainide, a new class Ic drug. These patients were prospectively followed-up for 10 +/- 11 months with pilsicainide. The rate of freedom from recurrence of paroxysmal atrial fibrillation attacks was significantly (P<0.0001) higher in patients with whom dispersion was decreased by the single dose (54%[7/13]) than in those in whom dispersion increased (8%[1/12]). CONCLUSION: Increased dispersion of signal-averaged P wave duration would play an important role in generating paroxysmal atrial fibrillation and would be useful in the prediction of drug efficacy to evaluate the change in dispersion by a single administration of pilsicainide.


Assuntos
Fibrilação Atrial/fisiopatologia , Mapeamento Potencial de Superfície Corporal , Taquicardia Paroxística/fisiopatologia , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antiarrítmicos/administração & dosagem , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Feminino , Seguimentos , Frequência Cardíaca , Humanos , Lidocaína/administração & dosagem , Lidocaína/análogos & derivados , Lidocaína/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Curva ROC , Recidiva , Taquicardia Paroxística/diagnóstico , Taquicardia Paroxística/tratamento farmacológico
10.
Heart ; 86(6): 656-60, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11711461

RESUMO

OBJECTIVE: To determine whether cardiac iodine-123 metaiodobenzylguanidine ((123)I MIBG) imaging is useful in predicting the prognosis of patients with chronic heart failure. DESIGN: Cardiac (123)I MIBG imaging was done on entry to the study. The cardiac MIBG washout rate was calculated from anterior chest view images obtained 20 and 200 minutes after injection of the isotope. Study patients were divided into two groups with washout rates above and below 27% (the mean value + 2 SD obtained in 20 normal subjects), and were then followed up. SETTING: Tertiary referral centre. PATIENTS: 79 patients with chronic heart failure in whom the left ventricular ejection fraction was less than 40%. RESULTS: There were 37 patients in group 1 (washout rate of >/= 27%) and 42 in group 2 (< 27%). During a follow up period of between 1 and 52 months, eight patients died suddenly and five died of worsening heart failure in group 1, while none died in group 2; 13 patients in group 1 and four in group 2 were admitted to hospital for progressive heart failure. Kaplan-Meier analysis showed that group 1 had a significantly higher mortality and morbidity (p = 0.001 and p < 0.001, respectively) than group 2. CONCLUSIONS: Cardiac (123)I MIBG washout rate seems to be a good predictor of prognosis in patients with chronic heart failure.


Assuntos
3-Iodobenzilguanidina , Insuficiência Cardíaca/diagnóstico por imagem , Compostos Radiofarmacêuticos , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Seguimentos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Prognóstico , Estudos Prospectivos , Cintilografia , Estudos Retrospectivos , Análise de Sobrevida , Disfunção Ventricular Esquerda/fisiopatologia
11.
Am J Physiol Heart Circ Physiol ; 280(1): H256-63, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11123240

RESUMO

We tested whether mitochondrial or sarcolemmal ATP-sensitive K(+) (K(ATP)) channels play a key role in ischemic preconditioning (IP) in canine hearts. In open-chest beagle dogs, the left anterior descending artery was occluded four times for 5 min each with 5-min intervals of reperfusion (IP), occluded for 90 min, and reperfused for 6 h. IP as well as cromakalim and nicorandil (nonspecific K(ATP) channel openers) markedly limited infarct size (6.3 +/- 1.2, 8.9 +/- 1.9, and 7.2 +/- 1.6%, respectively) compared with the control group (40.9 +/- 4.1%). A selective mitochondrial K(ATP) channel blocker, 5-hydroxydecanoate, partially blunted the limitation of infarct size in the animals subjected to IP and those treated with cromakalim and nicorandil (21.6 +/- 3.8, 25.1 +/- 4.6, and 19.8 +/- 5.2%, respectively). A nonspecific K(ATP) channel blocker, glibenclamide, completely abolished the effect of IP (38.5 +/- 6.2%). Intracoronary or intravenous administration of a mitochondria-selective K(ATP) channel opener, diazoxide, at >100 micromol/l could only partially decrease infarct size (19.5 +/- 4.3 and 20.1 +/- 4.4%, respectively). In conclusion, mitochondrial and sarcolemmal K(ATP) channels independently play an important role in the limitation of infarct size by IP in the canine heart.


Assuntos
Trifosfato de Adenosina/metabolismo , Coração/fisiologia , Precondicionamento Isquêmico Miocárdico , Mitocôndrias Cardíacas/fisiologia , Canais de Potássio/fisiologia , Sarcolema/fisiologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Circulação Colateral/efeitos dos fármacos , Circulação Coronária/efeitos dos fármacos , Cromakalim/farmacologia , Ácidos Decanoicos/farmacologia , Diazóxido/administração & dosagem , Diazóxido/farmacologia , Cães , Coração/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Hidroxiácidos/farmacologia , Técnicas In Vitro , Mitocôndrias Cardíacas/efeitos dos fármacos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Nicorandil/farmacologia , Bloqueadores dos Canais de Potássio , Canais de Potássio/agonistas , Sarcolema/efeitos dos fármacos , Vasodilatadores/farmacologia
12.
Hypertension ; 38(3): 404-11, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11566913

RESUMO

Chronic inhibition of NO synthesis induces cardiac hypertrophy independent of systemic blood pressure (SBP) by increasing protein synthesis in vivo. We examined whether ACE inhibitors (ACEIs) enalapril and temocapril and angiotensin II type-I receptor antagonists (angiotensin receptor blockers [ARBs]) losartan and CS-866 can block cardiac hypertrophy and whether changes in activation of 70-kDa S6 kinase (p70S6K) or extracellular signal-regulated protein kinase (ERK) are involved. The following 13 groups were studied: untreated Wistar-Kyoto rats and rats treated with NO synthase inhibitor Nomega-nitro-L-arginine methyl ester (L-NAME), D-NAME (the inactive isomer of L-NAME), L-NAME plus hydralazine, L-NAME plus enalapril (3 mg. kg(-1). d(-1)) or temocapril (1 or 10 mg. kg(-1). d(-1)), L-NAME plus losartan (10 mg. kg(-1). d(-1)) or CS-866 (1 or 10 mg. kg(-1). d(-1)), L-NAME plus temocapril-CS866 in combination (1 or 10 mg. kg(-1). d(-1)), and L-NAME plus rapamycin (0.5 mg. kg(-1). d(-1)). After 8 weeks of each experiment, ratios of coronary wall to lumen (wall/lumen) and left ventricular weight to body weight (LVW/BW) were quantified. L-NAME increased SBP, wall/lumen, and LVW/BW compared with that of control. ACEIs, ARBs, and hydralazine equally canceled the increase in SBP induced by L-NAME. However, ACEIs and ARBs equally (but not hydralazine) attenuated increase in wall/lumen and LVW/BW induced by L-NAME. The L-NAME group showed both p70S6K and ERK activation in myocardium (2.2-fold and 1.8-fold versus control, respectively). ACEIs inactivated p70S6K and ARBs inactivated ERK in myocardium, but hydralazine did not change activation of either kinase. Thus, ACEIs and ARBs modulate different intracellular signaling pathways, inhibiting p70S6K or ERK, respectively, to elicit equal reduction of cardiac hypertrophy induced by chronic inhibition of NO synthesis in vivo.


Assuntos
Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Cardiomegalia/prevenção & controle , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Cardiomegalia/etiologia , Cardiomegalia/fisiopatologia , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Enalapril/farmacologia , Inibidores Enzimáticos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Imidazóis/farmacologia , Losartan/farmacologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Miocárdio/enzimologia , Miocárdio/patologia , NG-Nitroarginina Metil Éster/farmacologia , Infiltração de Neutrófilos/efeitos dos fármacos , Olmesartana Medoxomila , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos WKY , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Proteínas Quinases S6 Ribossômicas/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas/metabolismo , Tetrazóis/farmacologia , Tiazepinas/farmacologia
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