Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 376-380, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701727

RESUMO

OBJECTIVE: To investigate whether salidroside (Sal) plays a part in protecting myocardial cell through reducing the myocardial ischemia and the apoptosis pathway of both death receptors and mitochondria in acute exhausted rats. METHODS: Male SD rats were randomly divided into 4 groups (n=6): control group(Con), acute exhaustive swimming group (EE), low-dose and high-dose Sal pre-treatment exhaustive swimming group (SLE, SHE). Rats were treated with Sal solution (15 or 30 mg/(kg·d)) or 0.9%NaCl (3 ml/(kg·d)) by intraperitoneal injection for 15 d, respectively. The Con group did not carry out swimming training. The next day after the end of intraperitoneal administration, the rats in EE, SLE and SHE group were forced to swim until they were exhausted followed the standard of Thomas. After the end of exhaustive exercise, the rats were anesthetized and the blood samples and hearts were collected immediately. The myocardial ischemia and hypoxia area and myocardial apoptosis index (AI) were also observed. Serum ischemia modified albumin (IMA), cardiac troponin I (cTnI), brain natriuretic peptide(BNP) and myocardial cell Bcl-2-associated X protein (Bax), B-cell lymphoma-2 (Bcl-2) were determined. The expressions of myocardial TNF receptor superfamily member 6 (Fas), cytochrome C (Cyto-c), aspartate proteolytic enzyme-3(Caspase-3), aspartate proteolytic enzyme-8(Caspase-8), and aspartate proteolytic enzyme-9(Caspase-9) were detected. RESULTS: Compared with the Con group, the myocardial ischemia and hypoxia area in EE group was increased significantly. The serum levels of IMA, cTnI and BNP, AI and Bax levels and cardiac Fas, Cyto-C, Caspase-3, Caspase-8 and Caspase-9 protein expressions of EE group were also increased significantly (P<0.01), while the protein expression of Bcl-2 in cardiac tissues was decreased significantly (P<0.01). Compared with the EE group, the myocardial ischemia and hypoxia area, serum levels of IMA, cTnI and BNP, AI and Bax levels, and the protein expressions of cardiac Fas, Cyto-C, Caspase-3, Caspase-8 and Caspase-9 in Sal group were all decreased significantly(P<0.01). while the protein expression of cardiac Bcl-2 in Sal group were increased significantly (P<0.01). CONCLUSION: Sal plays a role in protecting myocardial cell through reducing the myocardial ischemia and inhibiting myocardial cell apoptosis in exhaustive exercise rats. The mechanism of reducing myocardial cell apoptosis may be related to inhibiting the expressions of Fas, Cyto-C, Caspase-3, Caspase-8, Caspase-9 and increasing the expression of Bcl-2.


Assuntos
Apoptose , Fadiga/fisiopatologia , Glucosídeos/farmacologia , Coração/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Fenóis/farmacologia , Animais , Biomarcadores/sangue , Feminino , Masculino , Miocárdio/citologia , Condicionamento Físico Animal , Ratos , Ratos Sprague-Dawley
2.
Artigo em Inglês | MEDLINE | ID: mdl-30805019

RESUMO

Salidroside, a phenyl-propanoid glycoside isolated from the medicinal plant Rhodiola rosea, has potent cardioprotective effects, especially against myocardial hypoxia and reoxygenation injury. However, the molecular mechanism underlying its action is still unclear. The aim of this study was to determine the effect of salidroside on sodium channel current (INa) and transient outward potassium channel current (Ito) in H9C2 cardiomyocytes. H9C2 cells were subcultured under anoxic conditions to mimic myocardial hypoxia and subsequently treated with salidroside. Whole cell patch clamp was performed to determine the effect of hypoxia/reoxygenation and salidroside on myocardial electrophysiological properties. In the differentiated H9C2 cells, hypoxia/reoxygenation reduced INa and Ito amplitude, while salidroside significantly restored both and altered the INa and Ito activation/inactivation kinetics in a dose-dependent manner. Our findings demonstrate that salidroside protects myocardial cells against hypoxia-reoxygenation by restoring the function of sodium and potassium channels.

3.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 33(6): 531-534, 2017 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-29931903

RESUMO

OBJECTIVE: To study the role and mechanism of myocardial apoptosis after short-term and long-term exercise preconditioning. METHODS: Forty-eight male SD rats were randomly divided into control group (C), exhaust group (E), short-exercise preconditioning (S-EP) and long-term exercise preconditioning group (L-EP). Short-term and long-term exercise preconditioning were conducted for 3 days and 3 weeks of repeated intermittent swimming training program. The changes of myocardial cells were observed under light microscope. The serum levels of ischemia-modified albumin(IMA) and creatine kinase-isoenzyme(CK-MB) were detected by ELISA. Real time fluorescence quantitative PCR and Western blot were used to detect the expressions of tumor necrosis factor-α(TNF-α),Caspase-8, Caspase-3 genes and proteins in myocardial tissue. The apoptosis of cardiomyocytes was observed by TUNEL method. RESULTS: Compared with group C, group E had serious myocardial injury. The levels of serum IMA, CK-MB and the expressions of TNF-α, Caspase-8 and Caspase-3 in myocardium were increased (P<0.05). Compared with group E, serum CK-MB and TNF-α and Caspase-8 mRNA in S-EP group were significantly lower than those in group E (P<0.05), but there was no significant difference in serum IMA and Caspase-3 mRNA and protein (P>0.05). The levels of serum IMA, CK-MB and TNF-α, Caspase-8 and Caspase-3 mRNA in L-EP group were significantly lower than those in control group (P<0.05). The apoptosis of cardiomyocytes in group E was obvious. Short-term and long-term exercise preconditioning could inhibit apoptosis. Compared with S-EP group, the apoptosis of L-EP group was significantly decreased. CONCLUSIONS: Short-term and long-term exercise preconditioning can reduce myocardial injury after exhaustive exercise, but short-term exercise preconditioning does not alter the expression of Caspase protease. Long-term exercise preconditioning significantly inhibits Caspase-8, 3 mRNA expression and reduces protein synthesis. The inhibitive effects of long-term exercise preconditioning on myocardial cell apoptosis were stronger than those of short-term exercise preconditioning.


Assuntos
Traumatismo por Reperfusão Miocárdica/terapia , Miocárdio/patologia , Miócitos Cardíacos/citologia , Condicionamento Físico Animal , Animais , Apoptose , Biomarcadores , Caspase 3/metabolismo , Caspase 8/metabolismo , Creatina Quinase Forma MB/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Albumina Sérica/análise , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
4.
Chin J Integr Med ; 22(10): 738-44, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26906719

RESUMO

OBJECTIVE: To discuss the characteristics of Chinese medicine (CM) syndrome factors and distribution of congestive heart failure (CHF), and provide a basis for the diagnosis criteria of essential syndromes. METHODS: Based on databases of China National Knowledge Infrastructure (CNKI, 1980-2012) and Chinese Journal of Chongqing VIP Database (1989-2012), the eligible studies in CHF and extracted factors associated with compound syndromes were analyzed. All the syndromes were classified into deficiency, excess, and deficiency-excess in complexity syndrome were classified. Compound syndromes were separated into syndrome factors including single, double, three or four factors, along with the frequency of occurrence. The relation of CHF syndromes with age, gender, primary disease, brain natriuretic peptide (BNP) and cardiac functional grade was studied in 1,451 CHF cases (between December 2010 and September 2012), and the clinical distribution of common CHF syndromes was summarized. RESULTS: The literature study involved 6,799 CHF cases in 66 literatures after screening. Of the different factors affecting CHF, qi deficiency was the most important one. In deficiency syndrome, Xin (Heart)-qi-deficiency was the most common single factor, and deficiency of both qi and yin was the most common double factor. The retrospective analysis involved 1,451 CHF cases (431 cases with test results of BNP). The xin blood stasis and obstruction and deficiency of both qi and yin syndrome were mostly seen in female patients, and phlegm-blocking-Xin-vessel and qi-deficiency-blood-stasis syndrome mostly in males. Xin-qi-deficiency and qi-deficiency-blood-stasis syndrome were mostly seen in patients aged 50-60 years. Patients aged over 60 years likely manifest deficiency of both qi and yin and Xin blood stasis and obstruction syndrome. The severity of syndrome is aggravated with increased BNP and cardiac functional grade. CONCLUSIONS: The essential syndromes of CHF include qi-deficiency-blood-stasis and deficiency of both qi and yin. The clinical distribution is linked to patients' age and gender. BNP and cardiac functional grade is closely related to CHF syndromes, which may indicate the severity of CM syndromes of CHF.


Assuntos
Insuficiência Cardíaca/terapia , Medicina Tradicional Chinesa , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/metabolismo , Estudos Retrospectivos , Síndrome
5.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 32(2): 146-151, 2016 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29931867

RESUMO

OBJECTIVE: In order to provide the experimental basis for the prevention of exercise-induced cardiac injury, we evaluated the effects of nuclear factor erythroid-2-related factor2(Nrf2) on the changes of cardiac function and electrocardiogram in rats after exhaustive exercise. METHODS: SD rats were randomly divided into 5 groups (n=6):control group (Con), exhaustied exercise group (EE), 6h, 12 h, 24 h recovery from exhaustied exercise group(EER6 EER12 EER24). The animal models of exercise-induced myocardial injury were established according to Thomas' method.Rats were forced to swim until they were exhausted.The electrocardiograms were recorded in conscious rats. Cardiac function of rats was recorded and analyzed by Millar pressure-volume system. The changes of catalase(CAT), glutathione peroxidase(GPX), Nrf2 and reactive oxygen speies(ROS) were detected by ELISA, respectively. RESULTS: ①Compared with the control group and recovery groups(EER6, EER12, and EER24), the heart rate (HR), left ventricular end systolic pressure (Pes), arterial elasticity (Ea), the maximum rate of left ventricular pressure rise (dP/dtmax), peak rate of left ventricular pressure decline (-dP/dtmin) and left ventricular end diastolic pressure volume relationship curve slope (ESPVR) in the EE group decreased significantly, while left ventricular end diastolic volume (Ved), Pes, left ventricular end systolic volume (Ves), stroke volume, and Tau value increased significantly. Besides, HR, Pes, dP/dtmax, -dP/dtmin in recovery groups were significantly different with those in EE group, but there had no difference with those in the Con group. ②Compared with the control group, heart rate was increased, QT intervals were prolonged P wave, R wave and ST segments were increased in EE and recovery groups, but the changes of above-mentioned indexes in recovery groups had no statistical significant difference with those in EE group.③ Compared with the control group,the contents of ROS, Nrf2 were increased in EE group, while the content of GPX was decreased. Moreover, the content of CAT in EER6 group was the lowest in all groups. ④ The level of Nrf2 in serum was positively correlated with ROS and -dP/dtmin, and negatively correlated with HR, Ea. The level of ROS in Serum was positively correlated with EF, -dP/dtmin, and was negatively correlated with HR, Ea, dP/dtmax. CONCLUSIONS: Exhausted exercise caused changes of cardiac bioelectricity, impaired both the cardiac systolic and diastolic function, especially the diastolic disfunction. However, with recovery time after exhausted exercise prolonged, cardiac systolic and diastolic function recovered gradually, which was related to the reduced oxidative stress levels modulated by the increased Nrf2-induced changes of GPX and CAT.


Assuntos
Cardiomiopatias/fisiopatologia , Fator 2 Relacionado a NF-E2/sangue , Condicionamento Físico Animal/efeitos adversos , Animais , Pressão Sanguínea , Catalase/metabolismo , Eletrocardiografia , Glutationa Peroxidase/metabolismo , Frequência Cardíaca , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/sangue , Volume Sistólico , Função Ventricular Esquerda
6.
Oxid Med Cell Longev ; 2015: 876825, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26167242

RESUMO

OBJECTIVE: To test the hypothesis that salidroside (SAL) can protect heart from exhaustive exercise-induced injury by enhancing mitochondrial respiratory function and mitochondrial biogenesis key signaling pathway PGC-1α-NRF1/NRF2 in rats. METHODS: Male Sprague-Dawley rats were divided into 4 groups: sedentary (C), exhaustive exercise (EE), low-dose SAL (LS), and high-dose SAL (HS). After one-time exhaustive swimming exercise, we measured the changes in cardiomyocyte ultrastructure and cardiac marker enzymes and mitochondrial electron transport system (ETS) complexes activities in situ. We also measured mitochondrial biogenesis master regulator PGC-1α and its downstream transcription factors, NRF1 and NRF2, expression at gene and protein levels. RESULTS: Compared to C group, the EE group showed marked myocardium ultrastructure injury and decrease of mitochondrial respiratory function (P < 0.05) and protein levels of PGC-1α, NRF1, and NRF2 (P < 0.05) but a significant increase of PGC-1α, NRF1, and NRF2 genes levels (P < 0.05); compared to EE group, SAL ameliorated myocardium injury, increased mitochondrial respiratory function (P < 0.05), and elevated both gene and protein levels of PGC-1α, NRF-1, and NRF-2. CONCLUSION: Salidroside can protect the heart from exhaustive exercise-induced injury. It might act by improving myocardial mitochondrial respiratory function by stimulating the expression of PGC-1α-NRF1/NRF2 pathway.


Assuntos
Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Glucosídeos/farmacologia , Traumatismos Cardíacos/etiologia , Mitocôndrias/efeitos dos fármacos , Fenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos/uso terapêutico , Traumatismos Cardíacos/tratamento farmacológico , Masculino , Mitocôndrias/metabolismo , Músculo Esquelético/ultraestrutura , Miocárdio/metabolismo , Miocárdio/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 1 Nuclear Respiratório/genética , Fator 1 Nuclear Respiratório/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fenóis/uso terapêutico , Condicionamento Físico Animal , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Asian Pac J Trop Med ; 8(1): 64-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25901927

RESUMO

OBJECTIVE: To investigate the neuroprotective effects of simvastatin on lipopolysaccharide (LPS)-induced rat model of Parkinson's disease (PD) and the mechanisms involved. METHODS: Hemiparkinsonian rat models were induced by stereotaxieal injection of LPS in the right substantia nigra compacta. After 2 weeks of simvastatin treatment, rotational behavior test was performed after the intraperitoneal injection of apomorphine. Expression of tyroxine hydroxylase (TH) and glial fibrillary acidic protein were analyzed through immunohistochemical staining of substantia nigra and striatum, and the level of TNF- α was evaluated using enzyme-linked immunosorbent assay. RESULTS: Comparing with untreated group, behavioral symptoms of the rats were significantly less in the rats that received simvastatin treatment. The TH positive cell count in substantia nigra and striatum were significantly increased (P<0.05) and TNF- α expression was significantly decreased (P<0.05) in simvastatin group compared to untreated group. CONCLUSIONS: Simvastatin could effectively inhibit the activation of astrocytes, reduce TNF- α expression, and exert anti-inflammatory effects, and thus protect the dopaminergic neurons in substantia nigra and striatum of the rat model of PD.

8.
Chin Med J (Engl) ; 128(6): 784-9, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25758273

RESUMO

BACKGROUND: Current randomized trials have demonstrated the effects of short-term rosuvastatin therapy in preventing contrast-induced acute kidney injury (CIAKI). However, the consistency of these effects on patients administered different volumes of contrast media is unknown. METHODS: In the TRACK-D trial, 2998 patients with type 2 diabetes and concomitant chronic kidney disease (CKD) who underwent coronary/peripheral arterial angiography with or without percutaneous intervention were randomized to short-term (2 days before and 3 days after procedure) rosuvastatin therapy or standard-of-care. This prespecified analysis compared the effects of rosuvastatin versus standard therapy in patients exposed to (moderate contrast volume [MCV], 200-300 ml, n = 712) or (high contrast volume [HCV], ≥ 300 ml, n = 220). The primary outcome was the incidence of CIAKI. The secondary outcome was a composite of death, dialysis/hemofiltration or worsened heart failure at 30 days. RESULTS: Rosuvastatin treatment was associated with a significant reduction in CIAKI compared with the controls (2.1% vs. 4.4%, P = 0.050) in the overall cohort and in patients with MCV (1.7% vs. 4.5%, P = 0.029), whereas no benefit was observed in patients with HCV (3.4% vs. 3.9%, P = 0.834). The incidence of secondary outcomes was significantly lower in the rosuvastatin group compared with control group (2.7% vs. 5.3%, P = 0.049) in the overall cohort, but it was similar between the patients with MCV (2.0% vs. 4.2%, P = 0.081) or HCV (5.1% vs. 8.8%, P = 0.273). CONCLUSIONS: Periprocedural short-term rosuvastatin treatment is effective in reducing CIAKI and adverse clinical events for patients with diabetes and CKD after their exposure to a moderate volume of contrast medium.


Assuntos
Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/prevenção & controle , Meios de Contraste/efeitos adversos , Fluorbenzenos/uso terapêutico , Pirimidinas/uso terapêutico , Sulfonamidas/uso terapêutico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rosuvastatina Cálcica , Resultado do Tratamento
9.
Can J Physiol Pharmacol ; 92(3): 197-204, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24593784

RESUMO

The aims of this study were to examine the effects of doxazosin on contractile responses to 5-hydroxytryptamine (5-HT), carbachol, and histamine, and to compare them with those of prazosin, alfuzosin, and terazosin, and then characterize a pharmacological profile of the 5-HT-induced contractile response using preparations of isolated longitudinal muscle strips from the rabbit gastric body. The results from these preparations showed that the contraction response to 5-HT, but not to carbachol or histamine, was found to be dose-dependently potentiated by doxazosin and its enantiomers. The specific potentiation effect on 5-HT was not observed in the preparations that were treated with prazosin, terazosin, or alfuzosin. The contractile response to 5-HT and its potentiation by doxazosin were not affected by treatment with phenoxybenzamine. However, 5-HT-induced contraction was competitively antagonized by nefazodone (with pA2 value of 8.64 ± 0.17), and was almost completely inhibited by treatment with indomethacin. In conclusion, doxazosin, but not prazosin, alfuzosin, or terazosin, selectively potentiates 5-HT-induced contraction in the rabbit gastric body strips via an α1-adrenoceptor-independent mechanism, without chiral recognition of its enantiomers. Additionally, the contraction to 5-HT was found to be mediated via 5-HT(2) receptors, and was similar to PGs synthesis in the preparations.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Doxazossina/farmacologia , Músculo Liso/efeitos dos fármacos , Receptor 5-HT2A de Serotonina/metabolismo , Serotonina/farmacologia , Estômago/efeitos dos fármacos , Antagonistas de Receptores Adrenérgicos alfa 1/química , Animais , Doxazossina/química , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , Músculo Liso/fisiologia , Coelhos , Serotonina/metabolismo , Estereoisomerismo , Estômago/fisiologia
10.
Chin J Physiol ; 57(6): 343-9, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25575523

RESUMO

Chronic intermittent hypobaric hypoxia (CIHH) facilitates carotid sinus baroreflex (CSB) in adult rats, but the effect of CIHH on CSB in young rats is not known. The purpose of present study was to investigate the effect of CIHH on CSB in the young rat treated with CIHH from neonatal age, and the role of nitric oxide (NO) and Ca²âº in the effect of CIHH. Neonatal male Sprague-Dawley rats were randomly divided into three groups: 42-day CIHH treatment group (CIHH42), 56-day CIHH treatment group (CIHH56), and an age-matched control group (control). CIHH neonatal rats with the maternal rats were exposed to a simulated high-altitude hypoxia in a hypobaric chamber mimicking 5,000-m altitude (O2 at 11.1%) for 42 or 56 days, 6 h per day, respectively. Isolated carotid sinus perfusion technique was used to test CSB of the rats. After 42-day and 56-day CIHH exposure, the CSB of the rats was inhibited significantly, manifesting as decrease of peak slope (PS) and reflex decrease (RD), and increase of threshold pressure (TP), equilibrium pressure (EP) and saturation pressure (SP). This inhibitory effect was canceled by L-type calcium channel activator Bay K 8644, but not by nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME). The data showed that CIHH inhibited CSB in anesthetized young rats through blocking L-type calcium channels in carotid sinus baroreceptor.


Assuntos
Barorreflexo/fisiologia , Seio Carotídeo/fisiologia , Hipóxia/fisiopatologia , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/farmacologia , Animais , Animais Recém-Nascidos , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Ratos , Ratos Sprague-Dawley
12.
Artigo em Chinês | MEDLINE | ID: mdl-20684292

RESUMO

OBJECTIVE: To observe the effects of (-)doxazosin(DOX), (+)DOX and (+/-)DOX on serum lipid levels and the mortality rates of the rabbits fed by an atherogenic diet. METHODS: Male white New Zealand rabbits were fed by an atherogenic diet for 4 weeks. 8 rabbits whose serum TC <10 mmol/L were confirmed as normal diet group and were fed normally. 40 rabbits whose serum TC >10 mmol/L were randomly divided into 4 groups (n=10): atherogenic diet group, atherogenic diet with (-)DOX group, atherogenic diet with (+)DOX group and atherogenic diet with (+/-)DOX group, which were intraperitoneally injected with (-)DOX, (+)DOX and (+/-)DOX for 9 weeks respectively. Normal and atherogenic diet group were intraperitoneally injected with double distilled water. After 9 weeks administration of (+/-)doxazosin and its enantiomers, effects of the three agents on serum levels of total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were observed. RESULTS: The mortality rate of the rabbits fed by an atherogenic diet for 13 weeks was 40%, and it was much higher than that of the rabbits fed by a normal diet (10%). The mortality rates in the rabbits treated with (-)DOX and (+/-)DOX were lower than that in the rabbits fed by a normal diet (10%). Serum LDL-C level of the rabbits was increased markedly after 4 weeks of atherogenic diet, and it was further increased significantly (P < 0.05 and P < 0.01) during the continued 9 weeks of atherogenic diet. However, serum LDL-C levels were not further increased significantly (P > 0.05) during the continued 9 weeks of atherogenic diet in the rabbits treated with (-)DOX, (+)DOX and (+/-)DOX, respectively. CONCLUSION: (-)DOX and (+/-)DOX increase the survival rate and improve LDL-C disorder mildly in the rabbits fed by an atherogenic diet. The improvements in LDL-C induced by (-)DOX and (+/-)DOX, however, might not be the reason for exploration about the increased survival rate in the rabbits fed by an atherogenic diet.


Assuntos
Colesterol na Dieta/administração & dosagem , Doxazossina/farmacologia , Hiperlipidemias/tratamento farmacológico , Lipídeos/sangue , Animais , Dieta Aterogênica , Hiperlipidemias/sangue , Hiperlipidemias/etiologia , Masculino , Coelhos , Estereoisomerismo
13.
Zhonghua Xin Xue Guan Bing Za Zhi ; 34(8): 680-4, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17081388

RESUMO

OBJECTIVE: To investigate the influence of nitroglycerin tolerance (NT) on arterial ischemia (90 min) and reperfusion (120 min). METHODS: Male Sprague-Dawley rats were infused with nitroglycerin (GTN) or saline for 12 h and ascending aorta was rapidly isolated. The isolated aorta was subjected to one of the following treatments: stimulative ischemia/reperfusion, stimulative ischemia/reperfusion (I/R) plus glutathione (GSH, 0.1 mmol/L) during reperfusion, or control solution (Kreb's solution for 3.5 h). RESULTS: Compared with I/R group, contractile function, vasorelaxation responses to Ach, NO production were significantly decreased and CK, LDH activity as well as nitrotyrosine formation in reperfusion solution were significantly increased in I/R + NT group and these effects could be prevented with addition of GSH in I/R + NT aortas. CONCLUSIONS: Our results demonstrated that NT could aggravate arterial I/R injury by increasing the production of ONOO- and GSH may play a cardioprotective role against NT-induced myocardial injury by attenuating the formation of ONOO-.


Assuntos
Nitroglicerina/farmacologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Aorta/efeitos dos fármacos , Tolerância a Medicamentos , Glutationa/metabolismo , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Vasoconstrição
14.
J Cardiovasc Pharmacol ; 47(3): 405-12, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16633083

RESUMO

This study examined the potential deleterious effect of high-dose nitroglycerin (NTG) on cardiac function and cellular injury after ischemia (30 min) and reperfusion (120 min) in isolated perfused rat hearts. Low-dose (0.75 microg/h), medium-dose (3.75 microg/h), high-dose (15 microg/h) NTG or high-dose NTG plus glutathione (GSH, 1 mmol/L) was administrated at the time of reperfusion. Administration of high-dose NTG significantly exacerbated cardiac reperfusion injury as evidenced by increased creatine kinase and lactate dehydrogenase activity in coronary effluent, increased cardiomyocyte apoptosis and necrosis, and decreased cardiac function recovery after reperfusion. Compared with the vehicle group, formation of nitrotyrosine, a footprint for peroxynitrite (ONOO) production, was markedly increased in the hearts treated with medium-dose or high-dose NTG. Most interestingly, cotreatment with GSH blocked high-dose NTG-induced ONOO formation and attenuated myocardial ischemia/reperfusion injury. Taken together, our present results demonstrated that administration of high-dose NTG aggravated, rather than attenuated myocardial ischemia/reperfusion injury likely via increasing ONOO formation. Coadministration of GSH may reverse the advert action of high-dose NTG.


Assuntos
Glutationa/farmacologia , Isquemia Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/induzido quimicamente , Miócitos Cardíacos/efeitos dos fármacos , Nitroglicerina/toxicidade , Ácido Peroxinitroso/toxicidade , Animais , Apoptose/efeitos dos fármacos , Masculino , Contração Miocárdica/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/patologia , Ácido Peroxinitroso/metabolismo , Ratos , Ratos Sprague-Dawley , Tirosina/análogos & derivados , Tirosina/biossíntese
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA