Myocam s, by IonOptix - Product details

1

Contractility Assay of Isolated Myocytes

Check if the same lab product or an alternative is used in the 5 most similar protocols

Experiments were performed as previously described⁷ with some modification. Contractility was measured in custom-fabricated cell chambers (Ionoptix) mounted on an LSM Zeiss 880 inverted confocal microscope using a 40x oil 1.4 NA objective and transmitted light camera (IonOptix MyoCam-S). Myocytes were maintained in NT solution (for freshly isolated myocytes) or culture medium (without cytochalasin D, for cultured myocytes) at room temperature and electrical field stimulation was provided at 0.5 Hz with a myopacer (IonOptix MYP100) through platinum electrodes lowered into the bath. Sarcomere length was measured optically by Fourier transform analysis (IonWizard, IonOptix). After 10–30s of 0.5 Hz pacing to achieve steady state, five traces were recorded and analyzed. If not specified, contractility data was obtained at room temperature. The number of myocytes and hearts used in each experiments and further details are listed in Supplementary Table 6.
To test whether the contractile improvement with MT destabilization remains under more physiological conditions, both 0.5 Hz and 1Hz contractions at 37˚C were recorded and analyzed in a small subset of isolated human myocytes (1 NF and 1 failing heart, Supplementary Fig. 5c).

Yingxian Chen C., Caporizzo M.A., Bedi K., Vite A., Bogush A.I., Robison P., Heffler J.G., Salomon A.K., Kelly N.A., Babu A., Morley M.P., Margulies K.B, & Prosser B.L. (2018). Suppression of detyrosinated microtubules improves cardiomyocyte function in human heart failure. Nature medicine, 24(8), 1225-1233.

+ Open protocol

+ Expand

2

Calcium Transients in Ventricular Myocytes

Check if the same lab product or an alternative is used in the 5 most similar protocols

Calcium tolerant right ventricular myocytes were loaded with fura2-AM
ratiometric dye (Sigma, St Louis, MO, USA) at room temperature. Calcium
transients were recorded at 34 ± 2°C using IonOptix Calcium and
Contractility System equipped with a Hyperswitch and MyoCam-S (IonOptix,
Westwood, MA, USA). Myocytes were paced 2–6 Hz with field pacing using
Myopacer (IonOptix, Westwood, MA, USA). Bath solution contained (mM): NaCl 148,
KCl 5.4, CaCl₂ 1.8, MgCl₂ 1, HEPES 15, NaHPO₄0.4, D-glucose 5.5 and pH adjusted to 7.4 (NaOH). Diastolic calcium ratio was
analyzed (IonWizard, IonOptix; Origin 6). Each myocyte was paced for 1 minute
before recording 10 consecutive calcium transients for analysis. Cells from WT
and R67Q^+/− mice were used and calcium transients measured at
baseline and following incubation with isoproterenol (10 nM). In a separate set
of experiments, calcium tolerant right ventricular myocytes were paced for 30 s
at 2 Hz then treated with caffeine (10 mM) and sarcoplasmic reticulum (SR)
calcium content and Na⁺/Ca²⁺-exchanger (NCX) activity were
analyzed.

Reilly L., Alvarado F.J., Lang D., Abozeid S., Van Ert H., Spellman C., Warden J., Makielski J.C., Glukhov A.V, & Eckhardt L.L. (2020). Genetic Loss of IK1 Causes Adrenergic-induced Phase 3 Early Afterdepolarizations and Polymorphic and Bi-directional Ventricular Tachycardia. Circulation. Arrhythmia and electrophysiology, 13(9), e008638.

+ Open protocol

+ Expand

3

Cardiomyocyte Contractility and Ca2+ Dynamics

Check if the same lab product or an alternative is used in the 5 most similar protocols

Cardiomyocytes were incubated for 12.5 min with 5 µM Fura‐2/Acetoxymethyl ester (AM) in Krebs solution at 37°C, before application of protocols to mimic acute exercise or control in a perfusion cell bath (Krebs solution, 37°C, pH 7.3, CaCl₂ 1.8 mM) mounted on an inverted light microscope (Eclipse‐Ti, Nikon) with 40×/1.3 NA oil‐immersion objective. Electrical stimulation of 30 min at either 3 or 0.3 Hz of 5 ms pulse‐duration twitch trains were administered by platinum electrodes from a pulse generator and voltage stimulator (Digitimer Train/Delay Generator and Digitimer Constant Voltage Isolated Stimulator). Immediately following the acute exercise mimic or control, stimulation frequency was set to 1 Hz and increased to 6 Hz in 20–30 s steps while simultaneously recording contractile function by edge‐detection (Myocam‐S, IonOptix) and intracellular Ca²⁺ handling by ratiometric epifluorescence excitation at 500 Hz of 340/380 nm light that produced Ca²⁺‐sensitive emission collected at 505–525 nm by a photomultiplier tube (Optoscan, Cairn Research), calibrated for background noise (F/F₀). Records of 10 stable, consecutive contraction–relaxation and Ca²⁺‐transient cycles after steady‐state was reached at each stimulation frequency were analyzed for amplitudes and time‐courses (IonWizard 6.1, IonOptix).

Costa A.D., Ghouri I., Johnston A., McGlynn K., McNair A., Bowman P., Malik N., Hurren J., Bingelis T., Dunne M., Smith G.L, & Kemi O.J. (2023). Electrically stimulated in vitro heart cell mimic of acute exercise reveals novel immediate cellular responses to exercise: Reduced contractility and metabolism, but maintained calcium cycling and increased myofilament calcium sensitivity. Cell Biochemistry and Function, 41(8), 1147-1161.

+ Open protocol

+ Expand

4

Evaluating Cardiomyocyte Contractility via Sarcomere Imaging

Check if the same lab product or an alternative is used in the 5 most similar protocols

We used the IonOptix sarcomere detection and fast Fourier transform (FFT) method rather than Fluo-4 confocal imaging edge detection to measure cardiomyocyte contraction because the latter may lose precision if the cell's ends move out of the focal plane during contraction. Contraction was measured using an IonOptix system (IonOptix Co.) with a high-speed camera (MyoCam-S, 240 to 1000 frames/s) to record sarcomere movement during cardiomyocyte contraction. The sarcomere pattern was then used to calculate the sarcomere length using an FFT algorithm. The fractional shortening was then calculated as the percentage of change in sarcomere length during contraction.

Jian Z., Han H., Zhang T., Puglisi J., Izu L.T., Shaw J.A., Onofiok E., Erickson J.R., Chen Y.J., Horvath B., Shimkunas R., Xiao W., Li Y., Pan T., Chan J., Banyasz T., Tardiff J.C., Chiamvimonvat N., Bers D.M., Lam K.S, & Chen-Izu Y. (2014). Mechanochemotransduction During Cardiomyocyte Contraction Is Mediated by Localized Nitric Oxide Signaling. Science signaling, 7(317), ra27.

+ Open protocol

+ Expand

5

Contractility Assay of Isolated Myocytes

Check if the same lab product or an alternative is used in the 5 most similar protocols

Experiments were performed as previously described⁷ with some modification. Contractility was measured in custom-fabricated cell chambers (Ionoptix) mounted on an LSM Zeiss 880 inverted confocal microscope using a 40x oil 1.4 NA objective and transmitted light camera (IonOptix MyoCam-S). Myocytes were maintained in NT solution (for freshly isolated myocytes) or culture medium (without cytochalasin D, for cultured myocytes) at room temperature and electrical field stimulation was provided at 0.5 Hz with a myopacer (IonOptix MYP100) through platinum electrodes lowered into the bath. Sarcomere length was measured optically by Fourier transform analysis (IonWizard, IonOptix). After 10–30s of 0.5 Hz pacing to achieve steady state, five traces were recorded and analyzed. If not specified, contractility data was obtained at room temperature. The number of myocytes and hearts used in each experiments and further details are listed in Supplementary Table 6.
To test whether the contractile improvement with MT destabilization remains under more physiological conditions, both 0.5 Hz and 1Hz contractions at 37˚C were recorded and analyzed in a small subset of isolated human myocytes (1 NF and 1 failing heart, Supplementary Fig. 5c).

Yingxian Chen C., Caporizzo M.A., Bedi K., Vite A., Bogush A.I., Robison P., Heffler J.G., Salomon A.K., Kelly N.A., Babu A., Morley M.P., Margulies K.B, & Prosser B.L. (2018). Suppression of detyrosinated microtubules improves cardiomyocyte function in human heart failure. Nature medicine, 24(8), 1225-1233.

+ Open protocol

+ Expand

6

Calcium Transient Analysis of hiPSC-CMs

Check if the same lab product or an alternative is used in the 5 most similar protocols

To study the calcium‐handling properties, hiPSC‐derived cardiomyocytes were loaded with Fura‐2 AM (Life Technologies, Carlsbad, CA), a calcium indicator, at a working concentration of 1 μM for 20 minutes. Unincorporated dye was removed, and the cells were subsequently incubated in Tyrode solution. For calcium transient measurements, field‐stimulated electrical pacing was induced by the Myopacer EP Field Stimulator (IonOptix, Westwood, MA) at 40 V cm⁻¹, 5‐millisecond pulse duration at frequencies of 0.5 Hz, 1 Hz, 1.5 Hz, and 2 Hz. The calcium fluorescence and video‐edging (contractile force) signal were simultaneously recorded by MyoCam‐S (IonOptix) using IonWizard 6.4 version 2 software (IonOptix). The acquisition rate of calcium imaging was 100 points/s. The Fura‐2 required dual‐wavelength excitation at 340 nm and 380 nm, and the emission signals were recorded at 505 nm. The calcium level was presented as a ratio of 340/380 nm (F_340/380) and calibrated with amount of free calcium (nmol/L). The calcium transients of every cardiomyocyte were recorded with background subtraction.

Lee Y., Lau Y., Cai Z., Lai W., Wong L., Tse H., Ng K, & Siu C. (2017). Modeling Treatment Response for Lamin A/C Related Dilated Cardiomyopathy in Human Induced Pluripotent Stem Cells. Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease, 6(8), e005677.

+ Open protocol

+ Expand

7

Cardiomyocyte Contractility Dynamics

Check if the same lab product or an alternative is used in the 5 most similar protocols

Cardiomyocyte contraction was measured using the IonOptix Calcium & Contractility System with a high-speed camera (MyoCam-S, 1000 frames/sec), concurrent with the fluorescence measurements of

{Ca}^{2 +}

signals. Cells were continuously perfused with BTy solution and electrically stimulated at 0.5 Hz. The cardiomyocyte’s sarcomere length (SL) was measured from the striation pattern of the cell using the real-time fast Fourier transform (FFT). The cell contraction was measured by the fractional shortening of SL calculated as the percentage of the SL shortening to the diastolic SL.

Kazemi-Lari M.A., Shimkunas R., Jian Z., Hegyi B., Izu L., Shaw J.A., Wineman A.S, & Chen-Izu Y. (2022). Modeling cardiomyocyte mechanics and autoregulation of contractility by mechano-chemo-transduction feedback. iScience, 25(7), 104667.

+ Open protocol

+ Expand

8

Simultaneous Measurement of Cardiomyocyte Contractility and Calcium Transients

Check if the same lab product or an alternative is used in the 5 most similar protocols

Simultaneous measurements of CMC contractility and Ca²⁺ transients were carried out on an IonOptix system as previously described (Kondo et al., 2006 (link)). Briefly, CMCs loaded with 1 μM of the Ca²⁺ probe Fura-2 AM (Thermo Fisher Scientific) were placed in a perfusion system and continuously perfused with perfusion buffer (HBSS without Ca²⁺ and Mg²⁺, supplemented with 1.2 mM MgSO₄, 15 mM glucose, 30 mM taurine, and 1.0 mM MgCl₂), containing 1.0 mM CaCl₂ at 37°C. Loaded cells were paced at 0.5, 1.0, and 2.0 Hz, and sarcomere shortening and Fura-2 ratio (measured at 512 nm upon excitation at 340 and 380 nm) were simultaneously recorded on a Nikon Eclipse TE-2000S inverted fluorescence microscope with a 40×/1.3 NA objective and an attached CCD camera (MyoCam-S, IonOptix). Data acquisition and analysis were performed using Ion Wizard software, version 6.6.11 (IonOptix).

Filomena M.C., Yamamoto D.L., Carullo P., Medvedev R., Ghisleni A., Piroddi N., Scellini B., Crispino R., D'Autilia F., Zhang J., Felicetta A., Nemska S., Serio S., Tesi C., Catalucci D., Linke W.A., Polishchuk R., Poggesi C., Gautel M, & Bang M.L. (2021). Myopalladin knockout mice develop cardiac dilation and show a maladaptive response to mechanical pressure overload. eLife, 10, e58313.

+ Open protocol

+ Expand

9

High-Speed Imaging of Sarcomere Dynamics

Check if the same lab product or an alternative is used in the 5 most similar protocols

The images of contracting myocytes were recorded using a high speed camera (Myocam-S, 240 up to 1000 frame/s, IonOptix system). The sarcomere pattern along the longitudinal axis was used to calculate the sarcomere length during myocyte contraction in real time, by using a Fast Fourier Transform algorithm. The myocyte contraction was measured by the shortening of sarcomere length.

Jian Z., Chen Y.J., Shimkunas R., Jian Y., Jaradeh M., Chavez K., Chiamvimonvat N., Tardiff J.C., Izu L.T., Ross R.S, & Chen-Izu Y. (2016). In Vivo Cannulation Methods for Cardiomyocytes Isolation from Heart Disease Models. PLoS ONE, 11(8), e0160605.

+ Open protocol

+ Expand

10

Cardiomyocyte Contraction Dynamics

Check if the same lab product or an alternative is used in the 5 most similar protocols

After heart dissociation, a part of ventricular cardiomyocytes was kept at 4 °C in suspension in Tyrode solution containing 1 µM 9-Cis retinal, plated on the next day at low density on laminin-coated (0.1%) coverslips and superfused with Tyrode solution at ~35 °C. Cardiomyocytes were electrically (2 ms biphasic pulses, 40 V) paced at 0.5 Hz with two platinum electrodes and a stimulator (Myotronic). Contractions of single cardiomyocytes were recorded with an edge detection system (Myocam S and IonWizard software, Ionoptix). Data was recorded and analyzed with a Powerlab system and the LabChart software (AD Instruments). The average cell shortening of 11 contractions before illumination was compared with the average cell shortening of 11 beats around the maximal peak of cell shortening. Relaxation kinetics were determined by exponential decay fit from 85 to 15% of peak height.

Makowka P., Bruegmann T., Dusend V., Malan D., Beiert T., Hesse M., Fleischmann B.K, & Sasse P. (2019). Optogenetic stimulation of Gs-signaling in the heart with high spatio-temporal precision. Nature Communications, 10, 1281.

+ Open protocol

+ Expand

Myocam s

Lab products found in correlation

Close spelling variants of this product

15 protocols using myocam s

Contractility Assay of Isolated Myocytes

Calcium Transients in Ventricular Myocytes

Cardiomyocyte Contractility and Ca2+ Dynamics

Evaluating Cardiomyocyte Contractility via Sarcomere Imaging

Contractility Assay of Isolated Myocytes

Calcium Transient Analysis of hiPSC-CMs

Cardiomyocyte Contractility Dynamics

Simultaneous Measurement of Cardiomyocyte Contractility and Calcium Transients

High-Speed Imaging of Sarcomere Dynamics

Cardiomyocyte Contraction Dynamics

About PubCompare

Ready to get started?