Abstract:
:The effects of Cobra venom cardiotoxin (CTX) on the cellular morphology, twitch amplitude and intracellular calcium ([Ca2+]i) of the ventricular myocytes were studied. [Ca2+]i and twitch amplitude were determined with a fluorometric ratio method using Fura-2/AM and Calcium Green-1 as calcium indicators, and a videomicroscopic technique, respectively. Addition of 0.001-1 microM CTX led to a time-dependent loss of rod shaped cells, beginning at 1 min, and remaining stable by 20 min. CTX 1 microM initially caused a transient augmentation in amplitude of the electrically induced-[Ca2+]i transient and twitch amplitude in the single cardiac myocyte. This was followed by a prolongation in duration of [Ca2+]i. Eventually, cells became inexcitable and abruptly underwent contracture, and [Ca2+]i remained elevated. In the absence of electrical stimulation, 1 microM CTX induced a Ca2+ spike followed by a sustained elevation of [Ca2+]i, an effect different from that of 40 mm KCl or 10 mm caffeine, which caused a transient elevation in [Ca2+]i. Digital imaging microscopy of Calcium Green-1 fluorescence revealed that the increase in [Ca2+]i was accompanied by changes in cell shape without leakage of fluorescence dye in the early stage after administration of the toxin. In the absence of [Ca2+]o, the initial [Ca2+]i spike was reduced, but the second phase of elevation of [Ca2+]i still occurred. In addition, experiments using Mn2+ quench technique suggested that Ca2+-influx was induced by CTX, and that both ryanodine and thapsigargin, known to deplete Ca2+ from its intracellular pool, abolished the second phase of the elevation of [Ca2+]i. The effects of cardiotoxin were abolished by 10 mM Ni2+ and 10 mM -Ca2+-o, but not by 5 microM verapamil. In conclusion, the observations indicate that CTX causes an initial increase followed by a second sustained elevation in [Ca2+]i, which is accompanied by changes in cell shape-from rod to round-and hypercontracture. The initial [Ca2+]i spikes were attributed to the extracellular Ca2+ influx, while the second [Ca2+]i elevation was related to internal Ca2+ release. The high [Ca2+]i may be responsible for hypercontracture and cell death. Further studies are needed to verify it.
journal_name
J Mol Cell Cardioljournal_title
Journal of molecular and cellular cardiologyauthors
Wang HX,Lau SY,Huang SJ,Kwan CY,Wong TMdoi
10.1006/jmcc.1997.0511subject
Has Abstractpub_date
1997-10-01 00:00:00pages
2759-70issue
10eissn
0022-2828issn
1095-8584pii
S0022-2828(97)90511-3journal_volume
29pub_type
杂志文章abstract::Nitric oxide, which is produced endogenously within cardiac myocytes by three distinct isoforms of nitric oxide synthase, is a key regulator of myocardial function. This review will focus on the regulation of myocardial function by each nitric oxide synthase isoform during health and disease, with a specific emphasis ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章,评审
doi:10.1016/j.yjmcc.2008.07.015
更新日期:2008-11-01 00:00:00
abstract::Previously, we demonstrated protection against hypoxic injury in neonatal cardiac myocytes and reduced release of cardiac troponin I from perfused rat hearts by a novel peptide inhibitor [NH2-YGRKKRRQRRRMLATRALSLIGKRAISTSVCAGRKLALKTIDWVSFDYKDDDDK-] of the delta protein kinase C (δPKC) interaction with the "d" subunit ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2015.10.030
更新日期:2015-12-01 00:00:00
abstract::There is increasing evidence that pathological changes in the myocardium during chronic heart failure (CHF) are partly regulated through the activation of the renin-angiotensin system (RAS), an effect mediated by the angiotensin II type 1 receptor (AT1R). We examined the expression of cardiac AT1R mRNA in normal (atri...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1997.0458
更新日期:1997-08-01 00:00:00
abstract:BACKGROUND:Rodent cardiomyocytes (CM) undergo mitotic arrest and decline of mononucleated-diploid population post-birth, which are implicated in neonatal loss of heart regenerative potential. However, the dynamics of postnatal CM maturation are largely unknown in swine, despite a similar neonatal cardiac regenerative c...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2020.07.004
更新日期:2020-09-01 00:00:00
abstract::The specialized cardiac conduction system (CCS) consists of the sinoatrial node (SAN) and the atrioventricular (AV) conduction system (AVCS), which includes proximal (AV node, bundle of His and bundle branches) and distal (Purkinje fibers) components. In four CCS marker mice [two transgenic (cGATA6|lacZ, CCS|lacZ) and...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2007.02.008
更新日期:2007-05-01 00:00:00
abstract::AT1 receptor blockers (ARB) and in part ACE inhibitors (ACI) potentially exert beneficial effects on atherogenesis independent of AT1 receptor inhibition. These pleiotropic effects might be related to angiotensin II mediated activation of the AT2 receptor. To analyze this hypothesis we investigated the development of ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2011.12.007
更新日期:2012-03-01 00:00:00
abstract::The topic of this review is the lipidic part of the sarcolemma, the plasma membrane of the myocardial cell, and its role in (dis)function of the cardiomyocyte. First the isolation of the sarcolemma and its lipid composition are discussed. These phospholipids are not randomly distributed over the two monolayers of the ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章,评审
doi:10.1016/0022-2828(95)90080-2
更新日期:1995-02-01 00:00:00
abstract::31P-NMR was used to monitor myocardial bioenergetics in compensated and failing SHHF/MCC-fa(cp) (SHF) rat hearts. The SHHF/Mcc-fa(cp) (spontaneous hypertension and heart failure) rat is a relatively new genetic model in which all individuals spontaneously develop congestive heart failure, most during the second year o...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1997.0587
更新日期:1998-02-01 00:00:00
abstract::Previous animal experiments indicated that the effects of catecholamines on myocardial function and subcellular systems vary considerably depending on the species and type of myocardium investigated. In the present study, we used isometric force and heat measurements to investigate the influence of isoproterenol on en...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1994.1165
更新日期:1994-11-01 00:00:00
abstract::The incidence of mortality from cardiovascular diseases in higher in diabetic patients. The cause of this accelerated cardiovascular disease is multifactorial and, although atherosclerotic cardiovascular disease in association with well-defined risk factors has an influence on morbidity and mortality in diabetics, myo...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章,评审
doi:10.1016/s0022-2828(08)80016-8
更新日期:1995-01-01 00:00:00
abstract::There is currently a growing global burden of valvular heart diseases due to aging populations and changing lifestyles. Valvular heart diseases mainly include the malfunctioning of aortic and mitral valves and are characterized by extensive tissue remodeling, which includes calcification, endothelial dysfunction, and ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章,评审
doi:10.1016/j.yjmcc.2020.03.015
更新日期:2020-05-01 00:00:00
abstract::Redox stress during post-ischemic reperfusion may be the prime signal for processes leading to myocardial remodelling and hypertrophy. Nitric oxide (NO) is antioxidative, antiadhesive for neutrophils (PMN) and antiproliferative. Thus, enhancing endothelial production of NO, e.g. by inhibiting breakdown of endogenous b...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1997.0530
更新日期:1997-11-01 00:00:00
abstract::Lack of endothelial nitric oxide synthase (eNOS) may affect the sensitivity of cyclic GMP signaling through soluble guanylyl cyclase (sGC). We hypothesized that in eNOS knockout (eNOS-/-) mice, stimulation of guanylyl cyclase would have enhanced effects inhibiting cardiac contraction. We measured cell shortening and c...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2005.08.008
更新日期:2005-12-01 00:00:00
abstract::Although protection against necrosis has been observed in both hibernating (HIB) and ischemic preconditioned hearts in the second window of protection (SWOP), a comparison of the mitochondrial proteome between the two entities has not been previously performed. Anesthetized swine underwent instrumentation with a fixed...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2013.03.018
更新日期:2013-07-01 00:00:00
abstract::Myocardial protection during open heart surgery is achieved by general cooling and cold cardioplegia. However sympathetic activation during the operation causes raised circulating catecholamine levels that might negatively influence the myocardial metabolism. Moreover, local liberation of catecholamines, in "poorly pe...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/0022-2828(83)90276-6
更新日期:1983-04-01 00:00:00
abstract::We studied the presence of collagen degrading enzymes (matrix metalloproteinases, MMPs) in porcine myocardium following ischemia and late reperfusion. In nine pigs, left anterior descending coronary artery was occluded for 6 h followed by reperfusion for 3 h. Six pigs without coronary occlusion served as controls. Aft...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1998.0711
更新日期:1998-07-01 00:00:00
abstract::In view of considerable gaps in our knowledge of myocardial peroxisomes. the aim of the present study is, on the basis of extensive electron-microscopic investigations, to provide reliable results on the inducibility of a proliferation (increase in the number) of these organelles in rodents' heart by several agents an...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1996.0260
更新日期:1997-01-01 00:00:00
abstract::The question was investigated whether mild acidosis can provide energetic protection on the hypoxic myocardial cell by mechanisms other than negative inotropy. The experimental model used was quiescent ventricular cardiomyocytes isolated from the adult rat. The extracellular pH (pHe) in modified hypoxic Tyrode's solut...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/0022-2828(92)91159-3
更新日期:1992-01-01 00:00:00
abstract::Cardiac sarcoplasmic reticulum (SR) sequesters Ca2+ and plays a crucial role in the regulation of intracellular Ca2+. Its functional properties are central to the excitation-contraction (E-C) cycle of cardiac muscle. In this study, we examined the hypothesis that alterations in SR function occur during the development...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1996.0250
更新日期:1997-01-01 00:00:00
abstract::The self-perpetuation of atrial fibrillation (AF) is associated with atrial remodeling, including the degradation of the myofibril structure (myolysis). Myolysis is related to AF-induced activation of cysteine proteases and underlies loss of contractile function. In this study, we investigated which proteases are invo...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2008.08.012
更新日期:2008-11-01 00:00:00
abstract::Protein kinase C epsilon (PKCε) activation controls fibroblast growth factor-2 (FGF-2) angiogenic signaling. Here, we examined the effect of activating PKCε on FGF-2 dependent vascular growth and endothelial activation. ψεRACK, a selective PKCε agonist induces pro-angiogenic responses in endothelial cells, including f...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2013.07.006
更新日期:2013-10-01 00:00:00
abstract::The correlations between myocardial redox and energy states and atrial natriuretic peptide (ANP) secretion were studied in the perfused rat heart by exposing the hearts to global and low-flow ischemia for varying periods. Atrial and ventricular energy states and immunoreactive ANP in the effluent perfusate were measur...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/0022-2828(92)93155-d
更新日期:1992-02-01 00:00:00
abstract::Although cardiac failure can develop over time after myocardial infarction, the mechanism responsible for this is still unknown. The change of intracellular Ca2+ transport protein, such as sarcoplasmic reticulum (SR) Ca2+-ATPase (SR-Ca2+), Na+-Ca2+ exchanger (Na+-Ca2+), or cardiac phenotypic modulation of contractile ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1996.0270
更新日期:1997-01-01 00:00:00
abstract:BACKGROUNDS:Low serum cholesterol levels are associated with cardiac arrhythmias and poor prognosis in patients with chronic heart failure. However, the underlying mechanisms by which decreases in cholesterol content lead to cardiac dysfunction remain unclear. Multiple studies have implicated damage to cardiac transver...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2016.05.013
更新日期:2016-08-01 00:00:00
abstract::Quin2 is a fluorescent Ca2+-sensitive indicator which in its acetoxymethyl ester form can be loaded into the cytosolic compartment of cells without any disruption of the plasma membrane. Quin2 has been used with many cell types to measure changes of [Ca2+]i in response to hormones and other stimuli. In this report we ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/s0022-2828(86)80919-1
更新日期:1986-05-01 00:00:00
abstract::Myocardial perfusion measurement with colored microspheres may become an alternative for radioactive microsphere techniques. We use and validate a spectrophotometric method that has been previously established for large animals in the isolated perfused rat heart. The perfusion system was adapted for use in a NMR micro...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1006/jmcc.1996.0053
更新日期:1996-03-01 00:00:00
abstract::The sodium/potassium ATPase (NKA) is essential for establishing the normal intracellular [Na+] and [K+] and transmembrane gradients that are essential for many cellular functions, including cardiac electrophysiology and contractility. Different NKA isoforms exhibit differential expression levels, cellular localization...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2017.05.013
更新日期:2017-07-01 00:00:00
abstract::We studied the oxygen diffusion distance in the rabbit myocardium in untreated animals and in animals treated with thyroxine (T4) for 3 days and 16 days. The subepicardial and subendocardial regions were studied separately. Sixteen days of T4 treatment results in significant cardiac hypertrophy. After 16 days, the per...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/s0022-2828(88)80146-9
更新日期:1988-10-01 00:00:00
abstract::The effect of linoleic and arachidonic acid derivatives on ATP-dependent calcium transport was studied in the isolated vesicles from cardiac sarcoplasmic reticulum of guinea-pigs. Oxidation products of linoleic and arachidonic acids, obtained either by autoxidation or incubation with soybean lipoxygenase, effectively ...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/s0022-2828(88)80025-7
更新日期:1988-02-01 00:00:00
abstract::Neural structures have been shown to be present in valve cusp tissue. We aimed to characterise the influence of neuronal stimulation on the component structures of the aortic root and cusps. Specimens of sinus, sinotubular junction (STJ), annulus and cusp tissue were dissected from porcine aortic roots and either stim...
journal_title:Journal of molecular and cellular cardiology
pub_type: 杂志文章
doi:10.1016/j.yjmcc.2008.03.014
更新日期:2008-06-01 00:00:00