Abstract：
:This study was aimed to assess the relationship among the voltage-dependent processes underlying the excitation-contraction coupling, viz. force restitution (FR), transmembrane Ca fluxes and Ca release. The experiments (n = 22) were performed on voltage-clamped dog trabeculae in which force and slow inward current were measured. Standard steady-state was achieved by clamp driving at 0.5 Hz, 300 ms, 70 mV depolarizing pulses from holding = resting potential at 30 degrees C. Voltage and duration of single pulses and intervals in between were varied according to five protocols. The voltage dependence of Ca release was tested by varying single pulses at equal steady-state, i.e., at equal Ca availability. Contractions could be elicited in absence of ICa (20-30 mV step) and in the presence of disproportionately small ICa (above 80 mV). The voltage dependence of Ca availability for the release was tested by constant test pulses following either a variable conditioning clamp pulse or a period of rest at a variable voltage. After a low voltage pulse and, hence, depressed or absent ICa, the test contraction is diminished in presence of normal or even augmented Isi at any test interval (i.e., FR is depressed). Diminished Ca influx thus reduces the Ca availability of the subsequent beat. During prolonged depolarization (by 60 mV and more) a tonic response appears, but a phasic response cannot be elicited (FR is inhibited). Upon subsequent repolarization FR starts from zero and is significantly enhanced. It is concluded that, during depolarization, Ca release channels are in an open state, thus allowing free recirculation of Ca, but no build-up of a sufficient Ca gradient at the release site.
journal_name
Basic Res Cardioljournal_title
Basic research in cardiologyauthors
Bravený P,Simurda J,Simurdová Mdoi
10.1007/BF00795054keywords:
subject
Has Abstractpub_date
1992-09-01 00:00:00pages
418-27issue
5eissn
0300-8428issn
1435-1803journal_volume
87pub_type
杂志文章abstract：:Cardiomyopathy is one of the most common causes of chronic heart failure worldwide. Mutations in the gene encoding nexilin (NEXN) occur in patients with both hypertrophic and dilated cardiomyopathy (DCM); however, little is known about the pathophysiological mechanisms and relevance of NEXN to these disorders. Here, w...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-015-0522-5
更新日期：2016-01-01 00:00:00
abstract：:Protection from postconditioning has been documented in in situ animal models and it has been proposed that it is targeting circulating leukocytes. We therefore tested whether postconditioning can protect leukocyte-free, buffer-perfused rabbit hearts. Infarct size was measured with triphenyltetrazolium staining. In co...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-004-0498-4
更新日期：2005-01-01 00:00:00
abstract：:Atrial fibrosis is important for the pathogenesis of atrial fibrillation (AF) but the underlying signal transduction is incompletely understood. We therefore studied the role of microRNA-21 (miR-21) and its downstream target Sprouty 1 (Spry1) during atrial fibrillation. Left atria (LA) from patients with AF showed a 2...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-012-0278-0
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-017-0654-x
更新日期：2017-09-30 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章,评审
doi：10.1007/s003950050207
更新日期：1998-01-01 00:00:00
abstract：:Alterations in myocardial membrane phospholipids may play an important role in the pathogenesis of ischaemic myocardial cell injury. Studies in canine myocardium, perfused rat heart, and cultured myocardial cells have demonstrated that the accumulation of free arachidonic acid correlates with the development of irreve...
journal_title：Basic research in cardiology
pub_type： 杂志文章,评审
doi：10.1007/978-3-662-08390-1_15
更新日期：1987-01-01 00:00:00
abstract：:A methodological approach based on Frank's pressure-volume (P-V) diagram and model calculations for analyzing the determinants of stroke volume (SV) under conditions of altered ventricular geometrical configuration is discussed with respect to the underlying geometrical models. The approach is generalized in the sense...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF02190551
更新日期：1991-03-01 00:00:00
abstract：:The focal adhesion and microfilament-associated protein VASP is a major substrate of both cAMP- and cGMP-dependent protein kinase in intact human platelets. The recent elucidation of the primary VASP structure and identity of VASP binding proteins suggest that VASP is an important component of focal contacts which lin...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF00788712
更新日期：1996-09-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF00788873
更新日期：1993-11-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-010-0092-5
更新日期：2010-07-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF00788668
更新日期：1992-11-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章,评审
doi：10.1007/s00395-006-0616-1
更新日期：2006-09-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-008-0757-5
更新日期：2009-05-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-005-0532-9
更新日期：2005-07-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF01906388
更新日期：1975-09-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF00788284
更新日期：1994-09-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-010-0143-y
更新日期：2011-05-01 00:00:00
abstract：:Ischaemic preconditioning is one of the most potent experimental modalities known to decrease infarct size after ischaemia and reperfusion. Much interest has been stimulated by the phenomenon of remote ischaemic conditioning (RIC), in which the preconditioning stimulus is applied to a limb remote from the heart to sti...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-013-0377-6
更新日期：2013-09-01 00:00:00
abstract：:Persistent inflammatory responses participate in the pathogenesis of adverse ventricular remodeling after myocardial infarction (MI). We hypothesized that regulatory T (Treg) cells modulate inflammatory responses, attenuate ventricular remodeling and subsequently improve cardiac function after MI. Acute MI was induced...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-011-0232-6
更新日期：2012-01-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/978-3-642-72461-9_10
更新日期：1991-01-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF01935807
更新日期：1984-01-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s00395-004-0482-7
更新日期：2004-09-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF01923191
更新日期：1983-01-01 00:00:00
abstract：:Local photodynamic therapy was used to prevent neointimal hyperplasia after stenting. Slotted tube stents were placed with 16 atmospheres in porcine femoral arteries with the external diameter to match the diameter at 10 atmospheres. Animals were randomly allocated to Group 1 (stenting only); or Group 2 with stenting,...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s003950200003
更新日期：2002-03-01 00:00:00
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journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF01907787
更新日期：1976-01-01 00:00:00
abstract：:We investigated whether preconditioning could protect several cultured cell lines, to determine whether the protection is specific for cells derived from different myogenic and non-myogenic sources. Ischemia was simulated by centrifugation of cells into a pellet, and cell viability was determined by hypotonic trypan b...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/BF00788726
更新日期：1996-11-01 00:00:00
abstract：:The authors have retracted this article [1] because of modifications in the control lanes of Figs. 2a and 8a of the COX1 blot obtained for 18-week-old rats (rotation, horizontal flipping and re-use of the control lanes for the 35-week-old rats blot). In light of the concerns raised, the conclusions drawn in this artic...
journal_title：Basic research in cardiology
pub_type： 杂志文章,撤回出版物
doi：10.1007/s00395-018-0680-3
更新日期：2018-04-18 00:00:00
abstract：:Ischaemic preconditioning has not been demonstrated to reduce infarct size following global ischaemia in murine myocardium. Eighteen mouse hearts were isolated, perfused in the Langendorff mode, and randomised to control or preconditioning groups. Preconditioned hearts received four periods of five minutes global isch...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/s003950050106
更新日期：1998-10-01 00:00:00
abstract：:Cardioprotection aims at infarct size reduction and improvement of clinical outcome from myocardial infarction. The translation of cardioprotection from preclinical and promising proof-of-concept studies to clinical benefit for patients has been largely disappointing. Almost all of these studies which did not translat...
journal_title：Basic research in cardiology
pub_type： 杂志文章,评审
doi：10.1007/s00395-019-0756-8
更新日期：2019-10-15 00:00:00
abstract：:We investigated the force-frequency relationship (0.5-3 Hz) in non-failing human myocardium and in end-stage failing human myocardium due to dilated cardiomyopathy or subacute myocarditis. In non-failing myocardium, force of contraction increased with increasing stimulation frequency. In end-stage heart failure, the f...
journal_title：Basic research in cardiology
pub_type： 杂志文章
doi：10.1007/978-3-642-72474-9_17
更新日期：1992-01-01 00:00:00
