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1.
J Intensive Care Med ; 37(10): 1336-1343, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35285742

RESUMO

BACKGROUND: Pulmonary embolism (PE) with cor pulmonale causes considerable mortality and morbidity. Randomized trials have failed to show a mortality difference between treatment modalities including anticoagulation (AC), Catheter directed thrombolysis (CDT) and systemic tPA (tissue plasminogen activator). METHODS: This is a cross-sectional retrospective case-control study utilizing the 2017 National Inpatient Sample (NIS). Patients admitted with acute PE with cor pulmonale were divided into groups based on whether they received anticoagulation, CDT or systemic tPA based on appropriate ICD-10 PCS codes. The AC group and CDT group were compared using univariate and multivariate analyses after adjusting for age, gender, race, comorbidities, insurance status and Charlson comorbidity index (CCI). Secondary outcomes included factors influencing length of stay (LOS) and total charges incurred. Similar analyses were done to compare the CDT group with the tPA group. RESULTS: In 2017, 13240 patients were admitted with acute PE and cor pulmonale, of whom 18% underwent CDT, 10% underwent systemic tPA and 72% underwent AC alone. Patients who received CDT over AC alone were significantly younger (61.5 vs. 65.5, p = 0.00). Mortality rate overall was 4.8% with tPA group, CDT group and AC alone group having a 11.2%, 3.0% and 4.4% mortality rate respectively. On multivariate analyses, there was no significant mortality difference between the CDT and AC groups (aOR 0.61, 0.34-1.1 95%CI, p = 0.103). Patients with liver disease had significantly higher mortality while obese patients had a significantly lower mortality after adjusting for treatment strategy and confounders. Length of stay (LOS) was not significantly different between the groups however, compared to AC alone, patients who underwent CDT or tPA incurred significantly higher total hospital charges. CONCLUSIONS: CDT offers an attractive alternative to tPA therapy; however, our study does not show an in-hospital mortality benefit. More studies are required to guide patient selection prior to establishing treatment protocols.


Assuntos
Embolia Pulmonar , Doença Cardiopulmonar , Doença Aguda , Anticoagulantes , Estudos de Casos e Controles , Catéteres , Estudos Transversais , Fibrinolíticos/uso terapêutico , Humanos , Embolia Pulmonar/complicações , Embolia Pulmonar/tratamento farmacológico , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/tratamento farmacológico , Estudos Retrospectivos , Terapia Trombolítica/métodos , Fatores de Tempo , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
2.
Clin Exp Pharmacol Physiol ; 47(3): 478-484, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31730233

RESUMO

The right ventricle (RV) enlargement and pulmonary fibrosis are involved in cor pulmonale. The role of miR-200b in cor pulmonale is less well understood. This study was designed to evaluate the regulatory roles of miR-200b in cor pulmonale. Cor pulmonary mouse model was built via monocrotaline injection of monocrotaline (MCT). The expression of miR-200b in the lungs, RV and left ventricle (LV) are using real-time polymerase chain reaction. The transthoracic echocardiography was employed to determine the effects of miR-200b mimics and Gö6976 injection on MCT mice. The protein levels of protein kinase C α (PKCα), collagen, and fibronectin in the lung, RV, and LV in the mice with and without miR-200b mimics and Gö6976 injection were evaluated using western blot. The expression of miR-200b decreased in MCT mice, while there was no difference in LV. Both the miR-200b mimics and Gö6976 injection reversed the muscularization in the pulmonary artery, reversed RV hypertrophy, reduced RV systolic pressure, wall thickness and pulmonary fibrosis. The injection of miR-200b can reduce the PKCα expression in the lung, RV, and LV. This study confirmed the down-regulation of miR-200b in cor pulmonale. The reverse effects of miR-200b in the present study may provide a potential tool for cor pulmonary treatment.


Assuntos
Modelos Animais de Doenças , Hipertensão Pulmonar/metabolismo , MicroRNAs/metabolismo , Proteína Quinase C-alfa/biossíntese , Doença Cardiopulmonar/metabolismo , Transdução de Sinais/fisiologia , Animais , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monocrotalina/toxicidade , Proteína Quinase C-alfa/antagonistas & inibidores , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/prevenção & controle , Transdução de Sinais/efeitos dos fármacos
3.
Environ Health ; 18(1): 64, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307485

RESUMO

BACKGROUND: Pulmonary heart disease (PHD) has become a global burden, especially in low- and middle-income countries. However, very few studies have assessed the influence of air pollution on PHD. This is the first study to explore the association between gaseous pollutants and PHD-related mortality in the central Sichuan Basin of southwestern China. METHODS: Data on PHD-related mortality among elderly people (aged 60 and older) from 2013 to 2017 were collected from the Population Death Information Registration and Management System (PDIRMS). Data on air pollutants were collected from all 24 Municipal Environmental Monitoring Sites in Chengdu, and data on daily temperature, relative humidity, and atmospheric pressure were collected from the Chengdu Municipal Meteorological Bureau. An epidemiological design of time-stratified case-crossover was conducted to assess the association between short-term exposure to ambient gaseous pollutants and PHD-related mortality among elderly people. RESULTS: About 54,920 PHD-related deaths among people aged 60 and older were reported. After controlling for daily temperature, relative humidity, and atmospheric pressure, an IQR concentration increase in levels of sulfur dioxide (SO2) (13 µg/m3), nitrogen dioxide (NO2) (17 µg/m3), and ozone (O3) (74 µg/m3) was associated with 7.8, 6.2, and 5.5% increases in PHD-related mortality in people aged 60 and older, respectively. People over age 70 might have even higher susceptibility to PHD-related mortality associated with SO2, NO2, and O3. Females and individuals with alternative marital statuses (widowed, divorced, or never married) had twice and more than twice the PHD-related mortality risk associated with SO2 and NO2 than males and married individuals, respectively. CONCLUSIONS: Increased concentrations of ambient SO2, NO2, and O3 were significantly and positively associated with PHD-related mortality in Chengdu, China. Sociodemographic factors - including gender, age, and marital status - may modify the acute health effects of gaseous pollutants.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Exposição Ambiental , Gases/efeitos adversos , Doença Cardiopulmonar/mortalidade , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Cardiopulmonar/induzido quimicamente , Fatores de Tempo
4.
PLoS One ; 13(7): e0198681, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30044773

RESUMO

E-cigarettes are promoted as healthier alternatives to conventional cigarettes. Many cigarette smokers use both products. It is unknown whether the additional use of e-cigarettes among cigarette smokers (dual users) is associated with reduced exposure to tobacco-related health risks. Cross-sectional analysis was performed using baseline data from the Health eHeart Study, among English-speaking adults, mostly from the United States. Cigarette use (# cigarettes/day) and/or e-cigarette use (# days, # cartridges, and # puffs) were compared between cigarette only users vs. dual users. Additionally, we examined cardiopulmonary symptoms/ conditions across product use: no product (neither), e-cigarettes only, cigarettes only, and dual use. Among 39,747 participants, 573 (1.4%) reported e-cigarette only use, 1,693 (4.3%) reported cigarette only use, and 514 (1.3%) dual use. Dual users, compared to cigarette only users, reported a greater median (IQR) number of cigarettes per day, 10.0 (4.0-20.0) vs. 9.0 (3.0-15.0) (p < .0001), a lower (worse) median (IQR) SF-12 general health score, 3.3 (2.8-3.8) vs. 3.5 (2.8-3.9) (p = .0014), and a higher (worse) median (IQR) breathing difficulty score in the past month, 2.0 (1.0-2.0) vs. 1.0 (1.0-2.0) (p = .001). Of the 19 cardiopulmonary symptoms/ conditions, having a history of arrhythmia was significantly different between cigarette only users (14.2%) and dual users (17.8%) (p = .02). In this sample, dual use was not associated with reduced exposure to either (i) cigarettes, compared to cigarette only users or (ii) e-cigarettes, compared to e-cigarette only users. E-cigarette only use, compared to no product use, was associated with lower general health scores, higher breathing difficulty scores (typically and past month), and greater proportions of those who responded 'yes' to having chest pain, palpitations, coronary heart disease, arrhythmia, COPD, and asthma. These data suggest the added use of e-cigarettes alone may have contributed to cardiopulmonary health risks particularly respiratory health risks.


Assuntos
Asma/epidemiologia , Doença Cardiopulmonar/epidemiologia , Produtos do Tabaco/efeitos adversos , Vaping/efeitos adversos , Adulto , Asma/induzido quimicamente , Asma/fisiopatologia , Sistemas Eletrônicos de Liberação de Nicotina , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/fisiopatologia , Fatores de Risco , Nicotiana/efeitos adversos
5.
J Cardiovasc Pharmacol ; 66(3): 246-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25923321

RESUMO

Pulmonary arterial hypertension is characterized by progressive increases in resistance and pressure in the pulmonary artery and Cor pulmonale. The effect of exercise on hydrogen peroxide-dependent signaling in the right ventricle (RV) of Cor pulmonale rats was analyzed. Rats were divided into sedentary control (SC), sedentary monocrotaline (SM), trained control (TC), and trained monocrotaline (TM) groups. Rats underwent exercise training (60% of VO2 max) for 5 weeks, with 3 weeks after monocrotaline injection (60 mg/kg intraperitoneally). Pulmonary resistance was enhanced in SM (2.0-fold) compared with SC. Pulmonary artery pressure was increased in SM (2.7-fold) and TM (2.6-fold) compared with their respective controls (SC and TC). RV hypertrophy indexes increased in SM compared with SC. Hydrogen peroxide was higher in SM (1.7-fold) than SC and was reduced by 47% in TM compared with SM. p-Akt was increased in TM (2.98-fold) compared with SM. The Bax/Bcl-2 ratio and caspase 3 were also increased (2.9-fold and 3.9-fold, respectively) in SM compared with SC. Caspase 3 was decreased in TM compared with SM (P < 0.05). Therefore, exercise training promoted a beneficial response by decreasing hydrogen peroxide concentrations, and consequently, apoptotic signaling in RV.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Hipertrofia Ventricular Direita/fisiopatologia , Condicionamento Físico Animal/fisiologia , Artéria Pulmonar/fisiopatologia , Doença Cardiopulmonar/fisiopatologia , Animais , Apoptose/fisiologia , Modelos Animais de Doenças , Ecocardiografia , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Peróxido de Hidrogênio/metabolismo , Hipertrofia Ventricular Direita/metabolismo , Hipertrofia Ventricular Direita/patologia , Masculino , Monocrotalina/farmacologia , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/metabolismo , Doença Cardiopulmonar/patologia , Ratos Wistar , Resistência Vascular/fisiologia , Função Ventricular Direita/efeitos dos fármacos , Função Ventricular Direita/fisiologia , Remodelação Ventricular/efeitos dos fármacos , Remodelação Ventricular/fisiologia
6.
Dtsch Med Wochenschr ; 138(22): 1159-62, 2013 May.
Artigo em Alemão | MEDLINE | ID: mdl-23700302

RESUMO

HISTORY: A 32-year-old woman was admitted to the emergency department because of acute dyspnea and syncope. A few minutes before the onset of symptoms, she had self-administered an intravenous injection of one gram of heroin combined with grinded flunitrazepam tablets. INVESTIGATIONS: Signs of acute cor pulmonale were detected on transthoracic echocardiography despite lack of pulmonary embolism in computed tomography. It was assumed that microembolisms were the cause of acute pulmonary hypertension after intravenous injection of heroin and flunitrazepam. TREATMENT AND COURSE: Because of lack of thrombus in CT scan therapeutic anticoagulation with unfractionated heparin and oxygen insufflation was initiated resulting in rapid improvement of oxygen saturation and blood pressure. On the following day pulmonary pressure in transthoracic echocardiography was already decreased significantly. Without signs of deep venous thrombosis in duplex scan and only a marginal sub segmental perfusion deficit in ventilation-perfusion-scintigraphy therapeutic anticoagulation was recommended for three months. CONCLUSION: The most likely cause of micro embolisms in this case are particles of talc, which are often used to cut heroin, or the microcrystalline cellulose used in tablets. There have been reports of tissue necrosis due to arterial embolism/vasospasm by crystalloid or oily substances (embolia cutis medicamentosa) in the extremities after intraarterial injection of grinded flunitrazepam tablets. Therefore it seems plausible that intravenous application may cause a serve but transient deficit of perfusion in pulmonary circulation.


Assuntos
Flunitrazepam/toxicidade , Heroína/intoxicação , Doença Cardiopulmonar/induzido quimicamente , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/diagnóstico , Disfunção Ventricular Direita/induzido quimicamente , Adulto , Diagnóstico Diferencial , Feminino , Flunitrazepam/administração & dosagem , Heroína/administração & dosagem , Humanos , Doença Cardiopulmonar/diagnóstico , Doença Cardiopulmonar/terapia , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/terapia
7.
J Physiol Sci ; 63(1): 55-62, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23015108

RESUMO

Intravenous hyperosmotic NaCl infusion is an effective treatment for circulatory shock. However, a fast infusion rate (2 mL/kg at the rate of 1 mL/s) induces transient hypotension. This response has been reported to be due to decreased total peripheral resistance and/or decreased cardiac performance. Although the hypotension is transient and recovers within 2 min without detrimental consequences, it is important to understand the associated hemodynamics and mechanisms. We found that the hypotensive effect was larger with intravenous NaCl infusion than with intra-aortic infusion, indicating that change in cardiac performance played a more significant role than change in peripheral resistance. NaCl infusion induced an increase in pulmonary vascular resistance and central venous pressure and a decrease in right ventricular dP/dt max, suggesting acute cor pulmonale. Diastolic ventricular crosstalk-induced left ventricular failure was also observed. Hyperosmotic NaCl-induced hypotension was therefore mainly due to a combination of acute cor pulmonale and left ventricular failure.


Assuntos
Doença Cardiopulmonar/induzido quimicamente , Solução Salina Hipertônica/toxicidade , Cloreto de Sódio/toxicidade , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Pressão Venosa Central/efeitos dos fármacos , Pressão Venosa Central/fisiologia , Coração/efeitos dos fármacos , Coração/fisiopatologia , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Infusões Intravenosas , Masculino , Doença Cardiopulmonar/fisiopatologia , Ratos , Ratos Sprague-Dawley , Resistência Vascular/efeitos dos fármacos , Resistência Vascular/fisiologia , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/fisiopatologia
8.
Artigo em Chinês | MEDLINE | ID: mdl-22860411

RESUMO

OBJECTIVE: To explore the mechanism of pulmonary hypertension and Cor Pulmonale rat models induced by monocrotaline (MCT). METHODS: Twenty Wistar male rats were randomly divided into normal control group and model group (n= 10), which received a single intraperitoneal injection of MCT solution (50 mg/kg , the first day) or dissolvant, respectively. On day 28 after MCT administration, the hemodynamic parameters were assessed; levels of tumour necrosis factor-alpha (TNF-alpha), nitric oxide (NO), endothelin-1 (ET-1), B-type natriuretic peptide(BNP) in pulmonary tissue or blood were measured using radio immunoassay or nitrate reductase method. RESULTS: 28 days after MCT injection, compared with control group, right ventricle systolic pressure (RVSP) increased and heart rate(HR), mean arterial pressure (MAP) decreased; Levels of TNF-alpha, NO, ET-1 in pulmonary tissue or blood increased significantly in MCT group. CONCLUSION: The potential mechanism of MCI- induced pulmonary hypertension and Cor Pulmonale rat models associates with increasing TNF-alpha, NO, ET-1 levels in vivo, which results from inflammatory injury of lung tissue and blood vessels induced by MCT.


Assuntos
Hipertensão Pulmonar/fisiopatologia , Monocrotalina/efeitos adversos , Doença Cardiopulmonar/fisiopatologia , Animais , Modelos Animais de Doenças , Endotelina-1/metabolismo , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/metabolismo , Pulmão/metabolismo , Masculino , Óxido Nítrico/metabolismo , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
9.
Free Radic Biol Med ; 53(2): 216-29, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22583703

RESUMO

The development of pulmonary hypertension is a common accompaniment of congenital heart disease (CHD) with increased pulmonary blood flow. Our recent evidence suggests that asymmetric dimethylarginine (ADMA)-induced mitochondrial dysfunction causes endothelial nitric oxide synthase (eNOS) uncoupling secondary to a proteasome-dependent degradation of GTP cyclohydrolase I (GCH1) that results in a decrease in the NOS cofactor tetrahydrobiopterin (BH(4)). Decreases in NO signaling are thought to be an early hallmark of endothelial dysfunction. As l-carnitine plays an important role in maintaining mitochondrial function, in this study we examined the protective mechanisms and the therapeutic potential of l-carnitine on NO signaling in pulmonary arterial endothelial cells and in a lamb model of CHD and increased pulmonary blood flow (Shunt). Acetyl-l-carnitine attenuated the ADMA-mediated proteasomal degradation of GCH1. This preservation was associated with a decrease in the association of GCH1 with Hsp70 and the C-terminus of Hsp70-interacting protein (CHIP) and a decrease in its ubiquitination. This in turn prevented the decrease in BH(4) levels induced by ADMA and preserved NO signaling. Treatment of Shunt lambs with l-carnitine also reduced GCH1/CHIP interactions, attenuated the ubiquitination and degradation of GCH1, and increased BH(4) levels compared to vehicle-treated Shunt lambs. The increases in BH(4) were associated with decreased NOS uncoupling and enhanced NO generation. Thus, we conclude that L-carnitine may have a therapeutic potential in the treatment of pulmonary hypertension in children with CHD with increased pulmonary blood flow.


Assuntos
Acetilcarnitina/uso terapêutico , Células Endoteliais/efeitos dos fármacos , GTP Cicloidrolase/metabolismo , Hipertensão Pulmonar/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/metabolismo , Doença Cardiopulmonar/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Animais Recém-Nascidos , Arginina/análogos & derivados , Arginina/farmacologia , Biopterinas/análogos & derivados , Biopterinas/biossíntese , Modelos Animais de Doenças , Células Endoteliais/patologia , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/cirurgia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/metabolismo , Gravidez , Inibidores de Proteassoma/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/patologia , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/cirurgia , Ovinos , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
10.
South Med J ; 103(2): 116-20, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20065909

RESUMO

BACKGROUND: The occurrence of deteriorating renal function test results along with the attempts at diuresis of anasarca has been described but not named, and no solution other than the standard treatment of related medical conditions such as congestive heart failure (CHF) and reducing or stopping diuretics has been offered. Phosphodiesterase type 5 inhibitors (PD5I) are known to reduce pulmonary hypertension (PH). The PD5Is sildenafil and, just recently, tadalafil, have FDA indications in primary pulmonary hypertension (PPH). METHODS: In this observational study of CorPRADA patients treated with PD5I, 12 out of 19 cases met criteria for inclusion in statistical analysis. Medication reductions/discontinuations generally were made. Pre- and post-treatment data were analyzed using matched pairs. RESULTS: There were significant improvements in edema, glomerular filtration rate (GFR), weight, and loop diuretic dosage required, while strong trends were seen in urine output per day and urine output per unit loop diuretic per day. CONCLUSION: The identification of CorPRADA and the use of standard treatments for PH plus PD5I medication show promise in achieving successful diuresis of anasarca while stabilizing or improving renal function simultaneously.


Assuntos
Azotemia/tratamento farmacológico , Carbolinas/uso terapêutico , Diuréticos/uso terapêutico , Edema/tratamento farmacológico , Inibidores de Fosfodiesterase/uso terapêutico , Piperazinas/uso terapêutico , Doença Cardiopulmonar/tratamento farmacológico , Sulfonas/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Carbolinas/administração & dosagem , Diurese/efeitos dos fármacos , Diuréticos/efeitos adversos , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Inibidores de Fosfodiesterase/administração & dosagem , Piperazinas/administração & dosagem , Doença Cardiopulmonar/induzido quimicamente , Purinas/administração & dosagem , Purinas/uso terapêutico , Citrato de Sildenafila , Sulfonas/administração & dosagem , Tadalafila
11.
J Appl Toxicol ; 27(6): 538-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17351914

RESUMO

A study was conducted of acute intoxication of infant and adult Wistar rats with fluoroacetamide (FAA), an inhibitor of oxidative metabolism. FAA was administered orally to adult rats at 1/2 LD(50) and subcutaneously to infant rats at LD(100) or 1/10 LD(50). Electrocardiogram (ECG), respiration and motor activity were registered for 7 days. Clinical analysis of ECG and the heart rate variability (HRV) was carried out to assess the state of the vegetative nervous system. In adult rats, FAA caused marked disturbances in the activity of cardiovascular and respiratory systems, including the development of a potentially lethal acute cor pulmonale. Conversely, there were no significant changes of cardiac function and respiration in infant rats; they died because of extreme emaciation accompanied by retardation of development. In adult rats, bursts of associated cardiac and respiratory tachyarrhythmia, as well as regular high amplitude spasmodic sighs having a deca-second rhythm were observed. In both infant and adult rats, FAA caused short-term enhancement of humoral (metabolic) and sympathetic activities, followed by a gradual and stable predominance of parasympathetic influence on HRV. Under conditions of FAA inhibition of the tricarboxylic acid cycle, the observed physiological reactions may be explained by activation of alternative metabolic pathways. This is also supported by a lack of ontogenetically caused inhibition of spontaneous motor activity in infant rats poisoned with FAA, which highlights the significance of the alternative metabolic pathways for implementation of deca-second and minute rhythms and a lack of a rigid dependence of these rhythms upon activity of neuronal networks.


Assuntos
Envelhecimento , Inibidores Enzimáticos/toxicidade , Fluoracetatos/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Coração/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Respiração/efeitos dos fármacos , Doença Aguda , Administração Oral , Fatores Etários , Animais , Animais Recém-Nascidos , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/fisiopatologia , Relação Dose-Resposta a Droga , Eletrocardiografia , Metabolismo Energético/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Fluoracetatos/administração & dosagem , Coração/inervação , Injeções Subcutâneas , Sistema Nervoso Parassimpático/efeitos dos fármacos , Sistema Nervoso Parassimpático/fisiopatologia , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/fisiopatologia , Ratos , Ratos Wistar , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Fatores de Tempo , Testes de Toxicidade Aguda
15.
Toxicol Appl Pharmacol ; 118(1): 87-97, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8430429

RESUMO

Monocrotaline (MCT) produces pulmonary hypertension and right ventricular hypertrophy in rats. It is generally believed that MCT must undergo hepatic metabolism to reactive metabolites that are subsequently transported to the lungs to induce a pneumotoxic response. Several studies suggest that dehydromonocrotaline (MCTP) is the reactive intermediate that initiates pulmonary toxicity. We recently identified two other MCT metabolites, the glutathione and N-acetylcysteine conjugates of 6,7-dihydro-7-hydroxy-1-hydromethyl-5H-pyrrolizine (DHP). To determine the potential pulmonary toxicity of the glutathione conjugate (DHP-GSH) and the unacetylated cysteine conjugate precursor (DHP-Cys) of the N-acetylated excretion product, we conducted parallel in vivo toxicity studies with DHP-GSH, DHP-Cys, MCT, and MCTP. Relative pneumotoxicity was evaluated by measurements of right ventricular pressure (RVP), ventricular weight ratio (RV/LV+S), subjective histopathology, and measurements of components of the arteriolar wall. Animals given a single injection of MCT (60 mg/kg) developed pulmonary hypertension at the end of 3 weeks, as indicated by significant elevation in RVP when compared to the controls (22.1 +/- 2.4 mm Hg vs 13.2 +/- 0.8 mm Hg). A parallel and significant increase in RV/LV+S was also evident: 0.37 +/- 0.021 (MCT) vs 0.299 +/- 0.011 (control). Histopathology showed marked alterations in both pulmonary vasculature and parenchyma in MCT- and MCTP-treated animals. MCTP (1 mg/kg) caused a significantly elevated RVP (MCTP vs control: 28.1 +/- 3.4 mm Hg vs 16.8 +/- 0.97 mm Hg) and an increased RV/LV+S (MCTP vs control: 0.445 +/- 0.051 vs 0.284 +/- 0.026). Both MCT- and MCTP-treated rats had increased arteriolar medial thickness and decreased lumen diameter, but MCTP-treated rats had a milder vascular inflammatory response and less parenchymal lesions. Neither DHP-GSH (24 or 12 mg/kg) nor DHP-Cys (12 mg/kg) caused detectable changes in pulmonary circulation and no structural alteration in the lung was observed in these treatment groups. Although they are all pyrrolic metabolites of MCT, these studies demonstrate that only MCTP but not the glutathione or cysteine conjugates, is pneumotoxic at the doses tested.


Assuntos
Cisteína/toxicidade , Glutationa/toxicidade , Monocrotalina/análogos & derivados , Monocrotalina/toxicidade , Doença Cardiopulmonar/induzido quimicamente , Animais , Peso Corporal/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Monocrotalina/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Lab Invest ; 52(3): 298-303, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3156262

RESUMO

Methylprednisolone (MP) has been shown to reduce acute lung edema caused by monocrotaline (MCT), but its effect on MCT-induced pulmonary hypertension has not previously been reported. We have examined the effects of MP on MCT-induced pulmonary vascular remodeling and right ventricular hypertrophy using five groups of rats. Group 1 received nothing and acted as control; group 2 and all other groups received MCT as a single injection; group 3 was given low-dose MP by daily injection starting 24 hours after the MCT; group 4 was given MP as two high-dose pulses 2 hours before and 22 hours after MCT; group 5, acting as control for injection, received an injection of water 2 hours before MCT and daily for 21 days. All animals were killed 21 days after the MCT was given; ventricular weights were determined, and the lung vasculature was analyzed morphometrically. In each of the last three groups, the "treatment" reduced the increase in arterial medial thickness, "extension" of muscle to intraacinar pulmonary arteries, number of vessels with "occluded" lumen, and right ventricular hypertrophy--the features caused by MCT alone. For all four features, the effectiveness of a given regimen was similar. Daily MP prevented three-quarters of the ventricular ratio change, whereas pulse MP and daily water prevented one-half. The protection given by daily water injection may relate to autologous hormone production (steroid or other) from stress of injections. Daily MP, given after the acute MCT injury has occurred, protects more effectively than a high-dose pulse given at the time of injury. We suggest that the acute phase of MCT injury causes secondary changes that, although triggered by the acute lesion, become self-sustaining and are more significant for vascular structural remodeling.


Assuntos
Cardiomegalia/induzido quimicamente , Metilprednisolona/uso terapêutico , Doença Cardiopulmonar/induzido quimicamente , Alcaloides de Pirrolizidina , Animais , Peso Corporal , Cardiomegalia/tratamento farmacológico , Ventrículos do Coração , Hipertensão Pulmonar/patologia , Masculino , Monocrotalina , Doença Cardiopulmonar/tratamento farmacológico , Ratos , Ratos Endogâmicos
20.
Thorax ; 37(2): 88-96, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6281933

RESUMO

We have investigated the role of angiotensin converting enzyme (ACE) in the development of pulmonary hypertension, right ventricular hypertrophy, and pulmonary vascular disease in rats given a single subcutaneous injection of the pyrrolizidine alkaloid monocrotaline. Thirty-six young female Wistar rats were divided into a test group of 27 animals and a control group of nine animals. Each test rat was given a single subcutaneous injection of monocrotaline (60 mg/kg body weight). On the first, third, fifth, seventh, tenth, twelfth, fourteenth, seventeenth, and twenty-second days after the injection of monocrotaline the mean right ventricular systolic blood pressure was measured in one control and three test rats. The animals were then killed and we measured the specific activity of ACE in serum and lung homogenate. We also evaluated muscularisation of pulmonary arterioles, medial hypertrophy of muscular pulmonary arteries, and right ventricular hypertrophy. The sequence of changes was as follows: muscularisation of pulmonary arterioles and medial hypertrophy of muscular pulmonary arteries were apparent seven days after administration of monocrotaline; pulmonary hypertension and reduced lung ACE activity occurred after 10 days; right ventricular hypertrophy was detected after 12 days. Serum ACE activity was unchanged. It is concluded that the reduction in lung ACE activity is a result rather than a cause of the pulmonary hypertension. This reduction in lung ACE activity may be a protective mechanism designed to limit the elevation of the pulmonary arterial pressure.


Assuntos
Hipertensão Pulmonar/induzido quimicamente , Peptidil Dipeptidase A/sangue , Alcaloides de Pirrolizidina/efeitos adversos , Animais , Arteríolas/patologia , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/induzido quimicamente , Feminino , Hipertensão Pulmonar/enzimologia , Pulmão/análise , Pulmão/irrigação sanguínea , Pulmão/fisiopatologia , Monocrotalina , Músculo Liso Vascular/patologia , Artéria Pulmonar/patologia , Doença Cardiopulmonar/induzido quimicamente , Ratos , Ratos Endogâmicos
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