Free Shipping on orders over 50$

British Pound Sterling - GBP Euro - EUR US Dollar - USD (EUR)

Welcom to Gentaur Biotech Products!

Guinea Pig Cardiac Troponin_I ELISA

Be the first to review this product

Availability: In stock

€670.37
OR

Quick Overview

[#KT-505] Guinea Pig Cardiac Troponin_I ELISA

Details

Product Tags

Use spaces to separate tags. Use single quotes (') for phrases.

(1) Hypertrophic cardiomyopathy mutations increase myofilament Ca buffering, alter intracellular Ca handling, and stimulate Ca-dependent signaling.[TOP]

Pubmed ID :29760186
Publication Date : //
Mutations in thin filament regulatory proteins that cause hypertrophic cardiomyopathy (HCM) increase myofilament Ca sensitivity. Mouse models exhibit increased Ca buffering and arrhythmias, and we hypothesized that these changes are primary effects of the mutations (independent of compensatory changes) and that increased Ca buffering and altered Ca handling contribute to HCM pathogenesis via activation of Ca-dependent signaling. Here, we determined the primary effects of HCM mutations on intracellular Ca handling and Ca-dependent signaling in a model system possessing Ca-handling mechanisms and contractile protein isoforms closely mirroring the human environment in the absence of potentially confounding remodeling. Using adenovirus, we expressed HCM-causing variants of human troponin-T, troponin-I, and α-tropomyosin (R92Q, R145G, and D175N, respectively) in isolated guinea pig left ventricular cardiomyocytes. After 48 h, each variant had localized to the I-band and comprised ∼50% of the total protein. HCM mutations significantly lowered the of Ca binding, resulting in higher Ca buffering of mutant cardiomyocytes. We observed increased diastolic [Ca] and slowed Ca reuptake, coupled with a significant decrease in basal sarcomere length and slowed relaxation. HCM mutant cells had higher sodium/calcium exchanger activity, sarcoplasmic reticulum Ca load, and sarcoplasmic/endoplasmic reticulum calcium ATPase 2 (SERCA2) activity driven by Ca/calmodulin-dependent protein kinase II (CaMKII) phosphorylation of phospholamban. The ryanodine receptor (RyR) leak/load relationship was also increased, driven by CaMKII-mediated RyR phosphorylation. Altered Ca homeostasis also increased signaling via both calcineurin/NFAT and extracellular signal-regulated kinase pathways. Altered myofilament Ca buffering is the primary initiator of signaling cascades, indicating that directly targeting myofilament Ca sensitivity provides an attractive therapeutic approach in HCM.

Authors : Robinson Paul, Liu Xing, Sparrow Alexander, Patel Suketu, Zhang Yin-Hua, Casadei Barbara, Watkins Hugh, Redwood Charles,



(2) Ginseng total saponin attenuates myocardial injury via anti-oxidative and anti-inflammatory properties.[TOP]

Pubmed ID :26199551
Publication Date : //
Ginseng total saponin (GTS) contains various ginsenosides. These ginsenosides are widely used for treating cardiovascular diseases in Asian communities. The aim of this study was to study the effects of GTS on cardiac injury after global ischemia and reperfusion (I/R) in isolated guinea pig hearts.

Authors : Aravinthan Adithan, Kim Jong Han, Antonisamy Paulrayer, Kang Chang-Won, Choi Jonghee, Kim Nam Soo, Kim Jong-Hoon,



(3) The use of antibody modified liposomes loaded with AMO-1 to deliver oligonucleotides to ischemic myocardium for arrhythmia therapy.[TOP]

Pubmed ID :24468403
Publication Date : //
MicroRNA-1 (miR-1) has been found in cardiac and skeletal tissues. It is overexpressed in ischemic cardiac tissues. Down-regulation of miR-1 could relieve arrhythmogenesis by the anti-miR-1 antisense oligonucleotides (AMO-1). To increase the therapeutic efficiency and inhibit off-target effects of AMO-1, here we explored anti-cardiac troponin I (cTnI) antibody modified liposomes loading with AMO-1 (cT-A-LIP) to deliver the oligonucleotides to ischemic myocardium tissues. Liposomal cytotoxicity was assessed by MTT assay. The targeting abilities to foci were evaluated by in vivo imaging. The uptake and bio-distribution in vitro were observed by live cell station and flow cytometry, respectively. The anti-arrhythmic effects of cT-A-LIP in vivo were evaluated by electrocardiograms (ECG), immunohistochemistry, real-time PCR and patch-clamp recording. Immunohistochemistry showed that cTnI expression had a peak at the third day after myocardial infarction (MI). After cT-LIP administration via tail vein, accumulation of fluorescent trackers in the ischemic foci was significantly increased more than that of LIP. In addition, after cT-A-LIP administration, the ischemic arrhythmias were recovered and ST segment in ECG was elevated nearly back to normal. Compared with MI group, miR-1 expression was significantly down-regulated while Kir2.1 and CX43 protein expression were increased. Patch-clamp recordings showed that cT-A-LIP as well as AMO-1 incubation increased K(+) current density in guinea pigs ventricular cardiomyocytes acting on repolarized membrane potential. In conclusion, the cT-A-LIP not only delivered AMO-1 to ischemic myocardium in MI rats, but validated AMO-1 on relieving ischemic arrhythmia by silencing of miR-1 in ischemic myocardium and restoring the depolarized resting membrane potential (RMP) in MI rats.

Authors : Liu Meifang, Li Minghui, Sun Shouli, Li Baoxin, Du Dan, Sun Jialiang, Cao Fangyuan, Li Haichun, Jia Feng, Wang Tianfu, Chang Naidan, Yu Hui, Wang Qun, Peng Haisheng,



(4) Korean Red Ginseng Induced Cardioprotection against Myocardial Ischemia in Guinea Pig.[TOP]

Pubmed ID :23946687
Publication Date : //
This study was designed to evaluate the protective effect of Korean red ginseng (KRG) against ischemia/reperfusion (I/R) injury in isolated guinea pig heart. KRG has been shown to possess various ginsenosides, which are the major components of Panax ginseng. These components are known naturally occurring compounds with beneficial effects and free radical scavenging activity. The heart was induced to ischemia for 60 min, followed by 120 min reperfusion. The hearts were randomly allocated into five groups (n=8 for each group): normal control (N/C), KRG control, I/R control, 250 mg/kg KRG group and 500 mg/kg KRG group. KRG significantly increased hemodynamics parameters such as aortic flow, coronary flow and cardiac output. Moreover, KRG significantly increased left ventricular systolic pressure (LVSP), the maximal rate of contraction (+dP/dtmax) and maximal rate of relaxation (-dP/dtmax). Also, treatment of KRG ameliorated electrocardiographic index such as the QRS, QT and RR intervals. Moreover, KRG significantly suppressed the lactate dehydrogenase, creatine kinase-MB fraction and cardiac troponin I and ameliorated the oxidative stress markers such as malondialdehyde and glutathione. KRG was standardized through ultra performance liquid chromatograph analysis for its major ginsenosides. Taken together, KRG has been shown to prevent cardiac injury by normalizing the biochemical and oxidative stress.

Authors : Lim Kyu Hee, Kang Chang-Won, Choi Jin-Yong, Kim Jong-Hoon,



(5) Myocardial contractile and metabolic properties of familial hypertrophic cardiomyopathy caused by cardiac troponin I gene mutations: a simulation study.[TOP]

Pubmed ID :21967901
Publication Date : //
Familial hypertrophic cardiomyopathy (FHC) is an inherited disease that is caused by sarcomeric protein gene mutations. The mechanism by which these mutant proteins cause disease is uncertain. Experimentally, cardiac troponin I (CTnI) gene mutations mainly alter myocardial performance via increases in the Ca(2+) sensitivity of cardiac contractility. In this study, we used an integrated simulation that links electrophysiology, contractile activity and energy metabolism of the myocardium to investigate alterations in myocardial contractile function and energy metabolism regulation as a result of increased Ca(2+) sensitivity in CTnI mutations. Simulation results reproduced the following typical features of FHC: (1) slower relaxation (diastolic dysfunction) caused by prolonged [Ca(2+)](i) and force transients; (2) higher energy consumption with the increase in Ca(2+) sensitivity; and (3) reduced fatty acid oxidation and enhanced glucose utilization in hypertrophied heart metabolism. Furthermore, the simulation indicated that in conditions of high energy consumption (that is, more than an 18.3% increase in total energy consumption), the myocardial energetic metabolic network switched from a net consumer to a net producer of lactate, resulting in a low coupling of glucose oxidation to glycolysis, which is a common feature of hypertrophied hearts. This study provides a novel systematic myocardial contractile and metabolic analysis to help elucidate the pathogenesis of FHC and suggests that the alterations in resting heart energy supply and demand could contribute to disease progression.

Authors : Wu Bo, Wang Longhui, Liu Qian, Luo Qingming,



(6) Structure of trans-resveratrol in complex with the cardiac regulatory protein troponin C.[TOP]

Pubmed ID :21226534
Publication Date : //
Cardiac troponin, a heterotrimeric protein complex that regulates heart contraction, represents an attractive target for the development of drugs for treating heart disease. Cardiovascular diseases are one of the chief causes of morbidity and mortality worldwide. In France, however, the death rate from heart disease is remarkably low relative to fat consumption. This so-called "French paradox" has been attributed to the high level of consumption of wine in France, and the antioxidant trans-resveratrol is thought to be the primary basis for wine's cardioprotective nature. It has been demonstrated that trans-resveratrol increases the myofilament Ca(2+) sensitivity of guinea pig myocytes [Liew, R., Stagg, M. A., MacLeod, K. T., and Collins, P. (2005) Eur. J. Pharmacol. 519, 1-8]; however, the specific mode of its action is unknown. In this study, the structure of trans-resveratrol free and bound to the calcium-binding protein, troponin C, was determined by nuclear magnetic resonance spectroscopy. The results indicate that trans-resveratrol undergoes a minor conformational change upon binding to the hydrophobic pocket of the C-domain of troponin C. The location occupied by trans-resveratrol coincides with the binding site of troponin I, troponin C's natural binding partner. This has been seen for other troponin C-targeting inotropes and implicates the modulation of the troponin C-troponin I interaction as a possible mechanism of action for trans-resveratrol.

Authors : Pineda-Sanabria Sandra E, Robertson Ian M, Sykes Brian D,



(7) Solution structure of human cardiac troponin C in complex with the green tea polyphenol, (-)-epigallocatechin 3-gallate.[TOP]

Pubmed ID :19542563
Publication Date : //
Heart muscle contraction is regulated by Ca(2+) binding to the thin filament protein troponin C. In cardiovascular disease, the myofilament response to Ca(2+) is often altered. Compounds that rectify this perturbation are of considerable interest as therapeutics. Plant flavonoids have been found to provide protection against a variety of human illnesses such as cancer, infection, and heart disease. (-)-Epigallocatechin gallate (EGCg), the prevalent flavonoid in green tea, modulates force generation in isolated guinea pig hearts (Hotta, Y., Huang, L., Muto, T., Yajima, M., Miyazeki, K., Ishikawa, N., Fukuzawa, Y., Wakida, Y., Tushima, H., Ando, H., and Nonogaki, T. (2006) Eur. J. Pharmacol. 552, 123-130) and in skinned cardiac muscle fibers (Liou, Y. M., Kuo, S. C., and Hsieh, S. R. (2008) Pflugers Arch. 456, 787-800; and Tadano, N., Yumoto, F., Tanokura, M., Ohtsuki, I., and Morimoto, S. (2005) Biophys. J. 88, 314a). In this study we describe the solution structure of the Ca(2+)-saturated C-terminal domain of troponin C in complex with EGCg. Moreover, we show that EGCg forms a ternary complex with the C-terminal domain of troponin C and the anchoring region of troponin I. The structural evidence indicates that the binding site of EGCg on the C-terminal domain of troponin C is in the hydrophobic pocket in the absence of troponin I, akin to EMD 57033. Based on chemical shift mapping, the binding of EGCg to the C-terminal domain of troponin C in the presence of troponin I may be to a new site formed by the troponin C.troponin I complex. This interaction of EGCg with the C-terminal domain of troponin C.troponin I complex has not been shown with other cardiotonic molecules and illustrates the potential mechanism by which EGCg modulates heart contraction.

Authors : Robertson Ian M, Li Monica X, Sykes Brian D,



(8) 3-(R)-[3-(2-methoxyphenylthio-2-(S)-methylpropyl]amino-3,4-dihydro-2H-1,5-benzoxathiepine bromhydrate (F 15845) prevents ischemia-induced heart remodeling by reduction of the intracellular Na+ overload.[TOP]

Pubmed ID :19515969
Publication Date : //
The present study investigates whether 3-(R)-[3-(2-methoxyphenylthio-2-(S)-methylpropyl]amino-3,4-dihydro-2H-1,5-benzoxathiepine bromhydrate (F 15845), a new, persistent sodium current blocker, can reduce the ischemic Na(+) accumulation and exert short- and long-term cardioprotection after myocardial infarction. First, F 15845 concentration-dependently reduced veratrine-induced diastolic contracture (IC(50) = 0.14 microM) in isolated atria. Second, F 15845 from 1 microM preserved viability in 54.2 +/- 12.5% of isolated cardiomyocytes exposed to lysophosphatidylcholine. Third, the effect of F 15845 on intracellular Na(+) of isolated hearts from control and diabetic db/db mice was monitored using (23)Na-nuclear magnetic resonance spectroscopy. F 15845 (0.3 microM) significantly counteracted [Na(+)](i) increase during no-flow ischemia in control mouse hearts. In diabetic db/db mouse hearts, the reduction in [Na(+)](i) was delayed relative to control. However, it was more marked and maintained upon reperfusion. The cardioprotective properties after myocardial infarction associated with short- (24-h) and long-term (14-day) reperfusion were measured in anesthetized rats. After 24-h reperfusion, F 15845 (5 mg/kg) significantly reduced infarct size (32.4 +/- 1.7% with vehicle and 24.2 +/- 3.4% with F 15845; P < 0.05) and decrease of troponin I levels (524 +/- 93 microg/l with vehicle versus 271 +/- 63 microg/l with F 15845; P < 0.05). It is important that F 15845 limits the long-term expansion of infarct size (35.2 +/- 2.6%, n = 19 versus 46.7 +/- 1.6%, n = 27 in the vehicle group; P < 0.001). Overall, F 15845 attenuates [Na(+)](i) and prevents (or reverses) contractile and biochemical dysfunction in ischemic and remodeling heart. F 15845 constitutes a new generation of cardioprotective agent.

Authors : Vié Bruno, Sablayrolles Sylvie, Létienne Robert, Vacher Bernard, Darmellah Amaria, Bernard Monique, Feuvray Danielle, Le Grand Bruno,



(9) Differential effects of an expected actin-tropomyosin binding region of heat shock protein 20 on the relaxation in skinned carotid artery and taenia cecum from guinea pig.[TOP]

Pubmed ID :19377274
Publication Date : //
To explore the possible role of heat shock protein 20 (HSP20) -linked regulation of actin-myosin interaction in living vascular smooth muscle contraction, we studied the effects of HSP20p and TnIp, synthetic peptides originating from an actin tropomyosin binding region of human heat shock protein 20 [residues 110-121; GFVAREFHRRYR] and that of rabbit cardiac troponin I [residues 136-147; GKFKRPTLRRVR], respectively, on the active stress and phosphorylation level of myosin regulatory light chain (MLC(20)) during relaxation of skinned (cell membrane permeabilized) preparations from "tonic" carotid artery and "phasic" taenia cecum from guinea pig. Active stress of the skinned preparations, resulting from actin-myosin interaction, biphasically decayed following Ca(2+) removal (relaxation). Decay of MLC(20) phosphorylation level by Ca(2+) removal was much faster than active stress in an exponential manner. In skinned carotid artery, HSP20p did neither affect relaxation time course nor MLC(20) dephosphorylation, whereas, in skinned taenia cecum, the peptide slowed relaxation time course through inhibition of MLC(20) dephosphorylation and slowing "latch"-bridge dissociation. On the other hand, TnIp accelerated relaxation time course without affecting MLC(20) dephosphorylation in both skinned carotid artery and skinned taenia cecum. Our present results suggest that, HSP20p slows the relaxation processes through intracellular regulatory mechanisms such as Rho A/Rho-kinase mediated pathways, which are known to be dominant in "phasic" smooth muscles but to be recessive in "tonic" smooth muscles.

Authors : Hashimoto Ryo, Yumoto Masatoshi, Watanabe Masaru, Konishi Masato, Haraoka Jo, Miki Tamotsu,



(10) Lys184 deletion in troponin I impairs relaxation kinetics and induces hypercontractility in murine cardiac myofibrils.[TOP]

Pubmed ID :18096573
Publication Date : //
To understand the functional consequences of the Lys184 deletion in murine cardiac troponin I (mcTnI(DeltaK184)), we have studied the primary effects of this mutation linked to familial hypertrophic cardiomyopathy (FHC) at the sarcomeric level.

Authors : Iorga Bogdan, Blaudeck Natascha, Solzin Johannes, Neulen Axel, Stehle Ina, Lopez Davila Alfredo J, Pfitzer Gabriele, Stehle Robert,