Cardioscience最新文献_第5页

Delayed doxorubicin cardiomyopathy in the rat: possible role of reduced food intake. 大鼠迟发性阿霉素心肌病:食物摄入减少的可能作用。

Cardioscience Pub Date : 1994-06-01

M Canepari, V Cappelli, E Monti, L Paracchini, C Reggiani

引用次数: 0

Carnitine and cardiac interstitium. 肉毒碱和心脏间质。

Cardioscience Pub Date : 1994-06-01

W C Hülsmann, A Peschechera, E Arrigoni-Martelli

引用次数: 0

Secretion of atrial and brain natriuretic peptides from human cardiac atrial explants in culture: effect of dynorphin. 培养的人心脏心房外植体分泌心房和脑利钠肽:动啡的影响。

Cardioscience Pub Date : 1994-06-01

A Ationu, C Hassall, E Moules, M Patton, D R Singer, G Burnstock, N D Carter

引用次数: 0

Infusion of oxidized glutathione enhances postischemic segment-shortening in dog hearts. 灌注氧化谷胱甘肽增强狗心脏缺血后节段缩短。

Cardioscience Pub Date : 1994-06-01

H Krieter, S F Bauer, K Schwarz, K van Ackern, U B Brückner, J C Rüegg

{"title":"Infusion of oxidized glutathione enhances postischemic segment-shortening in dog hearts.","authors":"H Krieter, S F Bauer, K Schwarz, K van Ackern, U B Brückner, J C Rüegg","doi":"","DOIUrl":"","url":null,"abstract":"Oxidized glutathione (GSSG) but not its reduced form (GSH) is taken up by intact myocardial cells, and is rapidly converted into GSH. Reduced glutathione is an important intracellular defense against oxygen-derived free radicals and has been found to enhance calcium sensitivity in skinned cardiac fibers. We have investigated the effects of intravenous GSSG on left ventricular systolic pressure, maximal rate of rise of pressure and regional segment-shortening in dogs subjected to occlusion of the left anterior descending artery for 30 minutes, followed by 45 minutes reperfusion. Starting 10 minutes before reperfusion, the dogs were randomly treated with either GSSG (100 mM, 5 ml/min, n = 5) or Ringer's solution (5 ml/min, n = 5) until 30 minutes of reperfusion. Myocardial blood flow was measured by radioactive microspheres. Infusion of GSSG increased total glutathione content in both ischemic (47 +/- 16 mumol/g protein) and nonischemic myocardium (71 +/- 17 mumol/g protein) as compared to controls (23 +/- 2 mumol/g protein, p < 0.05). In both groups paradoxical wall motion occurred in the ischemic region during occlusion. On reperfusion, regional dyskinesia persisted in controls; while, in glutathione-treated dogs, systolic segment-shortening reached half the baseline values (p < 0.05, treated vs controls, at 15, 30, 45 minutes reperfusion). During ischemia the area of pressure-length loops, obtained from simultaneous recordings of left ventricular pressure and regional segment length, decreased to 30 +/- 7% of baseline in controls and to 40 +/- 18% of baseline in GSSG-treated animals. After 45 minutes reperfusion it was restored to 78 +/- 22% baseline in treated hearts but was still 36 +/- 16 of baseline in controls (p < 0.05). We conclude that infusion of GSSG increases the intracellular stores of glutathione and improves the contractile state of postischemic myocardium.","PeriodicalId":9629,"journal":{"name":"Cardioscience","volume":"5 2","pages":"115-26"},"PeriodicalIF":0.0,"publicationDate":"1994-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18917931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Usefulness and limitations of the positive protosystolic peak of coronary arterial blood flow as an index of epicardial arterial compliance. 冠状动脉血流原收缩阳性峰值作为心外膜动脉顺应性指标的有效性和局限性。

Cardioscience Pub Date : 1994-06-01

G Verlato, R Poltronieri

{"title":"Usefulness and limitations of the positive protosystolic peak of coronary arterial blood flow as an index of epicardial arterial compliance.","authors":"G Verlato, R Poltronieri","doi":"","DOIUrl":"","url":null,"abstract":"The aim of the study was to investigate the physiological meaning of the positive peak which appears at the onset of ventricular ejection on traces of blood flow in the left coronary artery. It was proposed that the protosystolic peak could represent systolic charging of epicardial coronary arterial compliance, i.e. the compliance which is not squeezed by myocardial contraction and which resides in superficial coronary arteries. To verify this hypothesis, blood flow was recorded from the left circumflex coronary artery in five anesthetized open-chest dogs and the protosystolic peak was identified by visual analysis or on the basis of zero-crossing of the first derivative. An index of epicardial compliance (delta V/delta P) was derived by dividing the peak area (delta V) by the aortic pulse pressure (delta P). Under basal conditions, the estimate of epicardial compliance, amounting to 0.271 +/- 0.149 x 10(-3) ml/mmHg (2.04 +/- 1.12 x 10(-12) m4s2kg-1; mean +/- SD), fell in the lower part of the range of values found by different authors and increased during hemorrhagic hypotension, due to nonlinearities of compliance in general. Similar values of epicardial compliance were obtained when a lumped resistance-capacitance parallel model was fitted to systolic coronary blood flow. Unexpectedly, however, the protosystolic peak was greatly decreased during coronary reactive hyperemia. We conclude that the protosystolic peak can be used as an index of epicardial compliance, but only at basal coronary vasomotor tone.","PeriodicalId":9629,"journal":{"name":"Cardioscience","volume":"5 2","pages":"87-94"},"PeriodicalIF":0.0,"publicationDate":"1994-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18917937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A characterized model of left ventricular hypertrophy in the rabbit. 兔左心室肥厚的特征性模型。

Cardioscience Pub Date : 1994-06-01

M A McIntosh, M N Hicks, K A Kane, A C Rankin, S M Cobbe

{"title":"A characterized model of left ventricular hypertrophy in the rabbit.","authors":"M A McIntosh, M N Hicks, K A Kane, A C Rankin, S M Cobbe","doi":"","DOIUrl":"","url":null,"abstract":"A rabbit model of left ventricular hypertrophy is characterized with respect to blood pressure, heart mass and ventricular refractoriness. Hypertension and left ventricular hypertrophy was induced by unilateral nephrectomy plus wrapping of the contralateral kidney in cellophane. Control or sham operated animals were subjected to a similar procedure except that the kidney was not wrapped in cellophane. No change in conscious mean arterial blood pressure was shown in the 11 sham operated animals (75 +/- 2 mmHg before operation and 75 +/- 3 mmHg 4-5 weeks after). Mean arterial pressure was increased from 73 +/- 2 to 99 +/- 3 mmHg by 4-5 weeks and had reached a plateau of 110 +/- 3 mmHg 5-6 weeks after operation in the 16 animals in which the kidney was wrapped. The ratios of left ventricular dry weight to body weight and of whole heart wet weight to body weight were significantly (p < 0.05) higher in the wrap group (0.38 +/- 0.01 and 2.97 +/- 0.12, respectively) than in the sham group (0.29 +/- 0.01 and 2.44 +/- 0.08 respectively). Effective refractory period, recorded from the left side of the arterially perfused interventricular septum, was greater in the wrap (266.1 +/- 8.9 ms) than in the sham group (228.2 +/- 3.5 ms). Linear correlations were shown between mean arterial pressure or effective refractory period vs the ratio of left ventricular dry weight to body weight or ratio of whole heart to body weight. This study has shown that hypertension induced by perinephritis caused left ventricular hypertrophy which was associated with a prolongation in ventricular refractoriness in the rabbit.","PeriodicalId":9629,"journal":{"name":"Cardioscience","volume":"5 2","pages":"95-100"},"PeriodicalIF":0.0,"publicationDate":"1994-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18915835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanical and metabolic responses to extracorporeal regional hypoperfusion of the porcine heart. 猪心脏体外局部灌注不足的机械和代谢反应。

Cardioscience Pub Date : 1994-06-01

R Tukkie, P F Gründeman, J W de Jong, P J Klopper

{"title":"Mechanical and metabolic responses to extracorporeal regional hypoperfusion of the porcine heart.","authors":"R Tukkie, P F Gründeman, J W de Jong, P J Klopper","doi":"","DOIUrl":"","url":null,"abstract":"Controversy exists as to whether hibernating myocardium is ischemic (with evidence of lactate production and ATP breakdown) during sustained coronary hypoperfusion or whether the oxygen supply is balanced by the oxygen requirements of contractile function. To investigate the mechanical and metabolic response to a moderate reduction in regional coronary blood flow, selective coronary perfusion was performed by a carotid-coronary shunt using a small roller pump circuit in six pigs. Flow was reduced for 45 minutes to 40% of base line followed by 2 hours reperfusion at normal blood flow. No hemodynamic changes occurred during flow reduction and reperfusion. Reduction of coronary blood flow to 40% resulted in a reduction in wall motion to 40.8 +/- 6.1% of base line. Two hours of reperfusion resulted in myocardial stunning shown by persistence of wall motion abnormalities (reduction to 64.6 +/- 6.0% of base line) without histologic and electron microscopic evidence of necrosis. The metabolic response to hypoperfusion varied from nil to substantial, measured as nucleotide catabolism and lactate production. We found no correlation between the base line normoxic contractile state and the magnitude of ischemic metabolite efflux. The efflux of lactate, inosine and uridine did not correlate with wall motion at each time during coronary flow reduction. Initial contractile recovery correlated with maximal lactate and uridine efflux during hypoperfusion. The results provide evidence that, in the in-vivo porcine myocardium, moderate coronary hypoperfusion can exist without metabolic evidence of ischemia.","PeriodicalId":9629,"journal":{"name":"Cardioscience","volume":"5 2","pages":"107-14"},"PeriodicalIF":0.0,"publicationDate":"1994-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18917930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Altered nucleus/cytoplasm relationship and degenerative structural changes in human dilated cardiomyopathy. 扩张型心肌病的核/细胞质关系改变和退行性结构改变。

Cardioscience Pub Date : 1994-06-01

D Scholz, W Diener, J Schaper

{"title":"Altered nucleus/cytoplasm relationship and degenerative structural changes in human dilated cardiomyopathy.","authors":"D Scholz, W Diener, J Schaper","doi":"","DOIUrl":"","url":null,"abstract":"We investigated systematically the structure of the myocardium obtained from patients with dilated cardiomyopathy undergoing transplantation because of intractable heart failure. Hearts were explanted at the time of surgery from 12 patients (10 men and 2 women, aged 31-57 years, ejection fraction < 20%) and numerous samples were taken for light and electron microscopy. Biopsies from the left ventricle of 8 patients during operations for atrial septal defect served as control tissue. The most obvious qualitative findings were focal hypertrophy and atrophy of myocytes, enlargement and bizarre shape of nuclei, lack of contractile material and occurrence of numerous small mitochondria. On a quantitative level, the nuclear density was reduced (18%, p < 0.05) but the nuclear profile area was significantly increased (85%, p < 0.001). Thus the nucleus/cytoplasm relationship was altered. The volume density of the contractile filaments was decreased (25%, p < 0.001), but the mitochondrial volume density was unchanged. There was an increase in cell width (39%, p < 0.01) and of the connective tissue content (= fibrosis) (112%, p < 0.001). It is suggested that the nuclear abnormalities may be the primary event in the pathogenesis of dilated cardiomyopathy. These may then lead to a reduced transcriptional rate which most probably is the cause of the lack of myofilaments and other degenerative changes. The deterioration of the structural quality of the hypertrophied myocytes results finally in atrophy and fibrosis and may be the structural correlate of functional disturbances in dilated cardiomyopathy.","PeriodicalId":9629,"journal":{"name":"Cardioscience","volume":"5 2","pages":"127-38"},"PeriodicalIF":0.0,"publicationDate":"1994-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18917932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preconditioning with hypoxia versus global ischemia in the isolated rat heart: effect on function and metabolism. 缺氧预处理对离体大鼠心脏缺血的影响:功能和代谢。

Cardioscience Pub Date : 1994-06-01

J A Moolman, S Genade, R Winterbach, A Lochner

{"title":"Preconditioning with hypoxia versus global ischemia in the isolated rat heart: effect on function and metabolism.","authors":"J A Moolman, S Genade, R Winterbach, A Lochner","doi":"","DOIUrl":"","url":null,"abstract":"It has recently been shown that hypoxia and ischemia are equally effective to precondition the myocardium of the rat. A comparison of the metabolic changes caused by transient ischemia and hypoxia has not yet been made and may help to elucidate the metabolic factors involved in eliciting preconditioning. The aim of this study was to compare the changes in tissue high energy phosphates, glycogen and lactate during and after hypoxic and ischemic preconditioning in isolated perfused rat hearts. Isolated rat hearts were subjected to global ischemia of 30 minutes duration, with and without preconditioning consisting of a single episode of 5 minutes global ischemia or hypoxia (PO2 = 12kPa). The post-ischemic recovery of aortic flow of the nonpreconditioned group was significantly less than that of the two preconditioned groups: 0.5 +/- 0.5 ml/min vs. 23.3 +/- 3.4 and 20.7 +/- 3.6 ml/min for ischemic and hypoxic preconditioning respectively. The only common metabolic factor between the two preconditioned groups was the similar extent of glycogenolysis after transient ischemia or hypoxia: glycogen decreased from 22 +/- 0.8 in non-preconditioned hearts to 16 +/- 0.5 and 16 +/- 1.5 mumoles glucose per g wet tissue in ischemic and hypoxic preconditioned hearts respectively. There was also no difference in lactate production between the two groups during the sustained episode of ischemia. We conclude that oxygen deprivation, rather than other metabolic factors, is the important factor in eliciting preconditioning.","PeriodicalId":9629,"journal":{"name":"Cardioscience","volume":"5 2","pages":"73-80"},"PeriodicalIF":0.0,"publicationDate":"1994-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18917935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Trials and tribulations of cardiac metabolism: the beginning. 心脏代谢的考验和磨难:开始。

Cardioscience Pub Date : 1994-06-01

R J Bing

引用次数: 0