Advances in myocardiology最新文献_第9页

Enhanced relaxation and reduced positive inotropic effects of amrinone in ventricular muscle from cats with subacute heart failure. Implications for drug therapy. 亚急性心力衰竭猫心室肌中氨利酮增强松弛和减少正性肌力作用。对药物治疗的启示。

Advances in myocardiology Pub Date : 1985-01-01

A L Bassett, M S Gaide, N J Lodge, J S Cameron

{"title":"Enhanced relaxation and reduced positive inotropic effects of amrinone in ventricular muscle from cats with subacute heart failure. Implications for drug therapy.","authors":"A L Bassett, M S Gaide, N J Lodge, J S Cameron","doi":"","DOIUrl":"","url":null,"abstract":"Previously, we reported that amrinone increases isometric twitch force but relaxes K+-induced contracture in muscles from normal cat right ventricle. This study evaluated its effects on diseased cardiac tissue. Right-ventricular papillary muscles were obtained from cats with subacute right-ventricular failure (3-14 days after partial pulmonary-artery ligation) and studied in vitro during stimulation (0.5 Hz) and exposure to high-K+ Tyrode solution. Active isometric twitch force and rate of force development (dP/dt) were significantly lower in muscles from hearts with right-ventricular failure compared to control muscles. In addition, while time to peak force was not different, duration of the twitch was significantly longer. In contrast to its positive inotropic actions in control muscles, amrinone (5.3 X 10(-4) M) had no significant effects on twitch force and dP/dt in muscles from failed ventricles. Time to peak force was not changed by amrinone in either group, but unlike its action in control muscle, duration of the twitch was reduced in failed muscle. Amrinone reduced K+-contracture force similarly in both control and failed muscles. Isoproterenol (10(-6) M) significantly increased twitch force and dP/dt and reduced K+-contracture force in both muscle groups. Since amrinone appears to be a phosphodiesterase inhibitor, our data indicate that cyclic AMP (cAMP)-related relaxation processes, but not cAMP-related contractile processes, can be enhanced by phosphodiesterase inhibitors in experimental heart failure. Furthermore, amrinone's reduced positive inotropic effect in failed myocardium suggests that its improvement of ventricular function in patients reflects, in part, enhancement of relaxation.","PeriodicalId":77831,"journal":{"name":"Advances in myocardiology","volume":"6 ","pages":"629-36"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14120322","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

Terminal nervous plexus of the atrioventricular junction of the rat. Microanatomical aspects and regional specialization. 大鼠房室交界处的末梢神经丛。微观解剖方面和区域专业化。

Advances in myocardiology Pub Date : 1985-01-01

M Moravec, A Courtalon, J Moravec

{"title":"Terminal nervous plexus of the atrioventricular junction of the rat. Microanatomical aspects and regional specialization.","authors":"M Moravec, A Courtalon, J Moravec","doi":"","DOIUrl":"","url":null,"abstract":"The paraformaldehyde-fixed hearts of adult rats were embedded in paraffin. Serial sections throughout the interatrial septum and the atrioventricular junction were examined in the optical microscope after having been silver stained. The density and the distribution of different nervous elements in the perinodal nerve plexus were studied and the results compared with the electron-microscopic data. These data confirm that at the level of the atrioventricular junction, a dense terminal network can be seen. It is composed of both terminal nerve fibers and ganglionic cells forming a small ganglion adjacent to the lower edge of the bundle of His and a thin ganglionic lamina in the interatrial septum. Apart from small neurons, previously described as cholinergic, large neurosecretory cells could also be demonstrated in some of the serial thin sections through the Hissian ganglion. The neuromuscular junctions between the terminal nerve fibers and specialized cells exhibit regional specialization. While the distal portion of the atrioventricular node and the bundle of His receive essentially efferent fibers, afferent coiled endings prevail in the reticular portion of the atrioventricular node and in the adjacent interatrial septum. Similar structures, larger in diameter, can also be seen around the muscular fibers and around the capillaries of the interventricular septum. The functional significance of the aforedescribed regional specialization of the terminal innervation of the atrioventricular junction is briefly discussed.","PeriodicalId":77831,"journal":{"name":"Advances in myocardiology","volume":"6 ","pages":"13-23"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15105853","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

Evidence for three catalytic sites in heart sarcolemmal phospholipid N-methylation. 心脏肌层磷脂n -甲基化三个催化位点的证据。

Advances in myocardiology Pub Date : 1985-01-01

P K Ganguly, V Panagia, N S Dhalla

引用次数: 0

The role of intracellular [Ca2+] and [H+] in contractile failure of the hypoxic heart. 细胞内[Ca2+]和[H+]在缺氧心脏收缩性衰竭中的作用。

Advances in myocardiology Pub Date : 1985-01-01

C H Orchard, D G Allen, P G Morris

{"title":"The role of intracellular [Ca2+] and [H+] in contractile failure of the hypoxic heart.","authors":"C H Orchard, D G Allen, P G Morris","doi":"","DOIUrl":"","url":null,"abstract":"When oxidative metabolism is inhibited in heart muscle, developed tension often increases slightly before decreasing below control. We have examined the possible mechanisms underlying these changes in developed tension in two series of experiments. In the first series of experiments, the photoprotein aequorin was used to monitor intracellular free [Ca2+] [( Ca2+]i) in papillary muscles during inhibition of oxidative phosphorylation, using either cyanide or hypoxia. The observed changes of developed tension were independent of changes in [Ca2+]i. It was therefore possible that these changes of tension were due to changes of intracellular pH (pHi). We tested this idea in a second series of experiments, using 31P nuclear magnetic resonance to monitor pHi, [ATP], and phosphocreatine concentration [( PCr]) in Langendorff-perfused ferret hearts. During the application of cyanide, pHi increased transiently before decreasing to below control. [PCr] decreased throughout this period, but [ATP] did not change. It is concluded that the observed changes of pHi could account for most of the observed changes of developed tension. It is suggested that the initial increase of pHi is due to PCr breakdown and the subsequent decrease of pHi to accelerated anaerobic glycolysis.","PeriodicalId":77831,"journal":{"name":"Advances in myocardiology","volume":"6 ","pages":"417-27"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15106648","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

Insulin action on cardiac glucose transport. Studies on the role of the sodium pump. 胰岛素对心脏葡萄糖转运的作用。钠泵作用的研究。

Advances in myocardiology Pub Date : 1985-01-01

J Eckel, H Reinauer

引用次数: 0

Infarct-size limitation--real or artifactual. Studies with flurbiprofen using a reperfusion model. 梗死面积限制——真实的或人为的。氟比洛芬再灌注模型的研究。

Advances in myocardiology Pub Date : 1985-01-01

D M Yellon, M P Maxwell, D J Hearse, S Yoshida, L Eddy, J M Downey

{"title":"Infarct-size limitation--real or artifactual. Studies with flurbiprofen using a reperfusion model.","authors":"D M Yellon, M P Maxwell, D J Hearse, S Yoshida, L Eddy, J M Downey","doi":"","DOIUrl":"","url":null,"abstract":"With the use of tetrazolium staining and risk-zone analysis, flurbiprofen has previously been shown to limit infarct size at 6 hr but not at 24 hr following coronary embolization in the dog heart. This study was designed to assess whether this delay in the development of a histologically defined infarct was real or an artifact arising from the effect of the drug on tetrazolium staining characteristics. With the use of a closed-chest bead-embolization model with a capability for reperfusion, hearts were made ischemic for 4 hr by injecting a 2.5 mm bead attached to a silk thread through a special cannula into the coronary vasculature. Immediately following occlusion, radioactive microspheres (141Ce) were administered to define the zone at risk of infarction. Hearts were divided into treatment (flurbiprofen, 1 mg/kg every 6 hr, N = 7) and control (saline, N = 7) groups. Following 4 hr of ischemia, the ischemic area was reperfused by withdrawing the thread and attached bead. Twenty hours later, the hearts were removed and transverse sections (3 mm) were prepared. The area of necrosis was visualized by tetrazolium staining and the risk zone by microsphere autoradiography. In control hearts, 24.7 +/- 5.0% of the zone at risk deteriorated to necrotic tissue; in the flurbiprofen-treated hearts, 17.4 +/- 4.3% of the risk zone became necrotic (NS, p greater than 0.10). Thus, despite earlier findings, these results suggest that the apparent delay in the development of tissue injury may be artifactual.","PeriodicalId":77831,"journal":{"name":"Advances in myocardiology","volume":"6 ","pages":"619-27"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15103909","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

The role of lysosomes and microtubules in cardiac protein degradation. 溶酶体和微管在心脏蛋白降解中的作用。

Advances in myocardiology Pub Date : 1985-01-01 DOI: 10.1007/978-1-4757-1287-2_10

K Wildenthal, J S Crie, J M Ord, J R Wakeland

引用次数: 3

Accelerated recovery of ischemic canine myocardium induced by AMP. Preliminary report. AMP对犬缺血心肌加速恢复的初步报道。

Advances in myocardiology Pub Date : 1983-07-01 DOI: 10.1016/0022-2828(83)91070-2

H. Sami, J. Koke, N. Bittar

引用次数: 1

Abstract of free communicationsUltrastructure of sarcoplasmic reticulum in the ischemic myocardium 自由通讯摘要缺血心肌肌浆网的结构

Advances in myocardiology Pub Date : 1983-07-01 DOI: 10.1016/0022-2828(83)91038-6

K. Akiyama, Takashi Katagiri, N. Konno, T. Yanagishita, F. Tanno, H. Kanaya, S. Sekita, M. Yokoyama, Y. Takeyama, Hirokazu Niitani, Yasumitsu Nakai

引用次数: 3

Perturbations of sarcolemmal and microsomal enzymes by amphiphilic lipids and drugs. 两亲性脂类和药物对肌上皮和微粒体酶的干扰。

Advances in myocardiology Pub Date : 1983-07-01 DOI: 10.1016/0022-2828(83)91063-5

W. Weglicki, J. Kramer, F. F. Kennett, T. Knauer, K. Owens

引用次数: 1