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Tian J, Tu C, Huang B, Liang Y, Zhou J, Ye X. Study of the union method of microelectrode array and AFM for the recording of electromechanical activities in living cardiomyocytes. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2016; 46:495-507. [PMID: 28012038 DOI: 10.1007/s00249-016-1192-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 10/08/2016] [Accepted: 11/30/2016] [Indexed: 11/28/2022]
Abstract
Electrophysiology and mechanics are two essential components in the functions of cardiomyocytes and skeletal muscle cells. The simultaneous recording of electrophysiological and mechanical activities is important for the understanding of mechanisms underlying cell functions. For example, on the one hand, mechanisms under cardiovascular drug effects will be investigated in a comprehensive way by the simultaneous recording of electrophysiological and mechanical activities. On the other hand, computational models of electromechanics provide a powerful tool for the research of cardiomyocytes. The electrical and mechanical activities are important in cardiomyocyte models. The simultaneous recording of electrophysiological and mechanical activities can provide much experimental data for the models. Therefore, an efficient method for the simultaneous recording of the electrical and mechanical data from cardiomyocytes is required for the improvement of cardiac modeling. However, as far as we know, most of the previous methods were not easy to be implemented in the electromechanical recording. For this reason, in this study, a union method of microelectrode array and atomic force microscope was proposed. With this method, the extracellular field potential and beating force of cardiomyocytes were recorded simultaneously with a low root-mean-square noise level of 11.67 μV and 60 pN. Drug tests were conducted to verify the feasibility of the experimental platform. The experimental results suggested the method would be useful for the cardiovascular drug screening and refinement of the computational cardiomyocyte models. It may be valuable for exploring the functional mechanisms of cardiomyocytes and skeletal muscle cells under physiological or pathological conditions.
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Affiliation(s)
- Jian Tian
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, 310027, People's Republic of China.,Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China
| | - Chunlong Tu
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, 310027, People's Republic of China.,Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China
| | - Bobo Huang
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, 310027, People's Republic of China.,Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China
| | - Yitao Liang
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, 310027, People's Republic of China.,Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China
| | - Jian Zhou
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, 310027, People's Republic of China.,Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China
| | - Xuesong Ye
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, 310027, People's Republic of China. .,Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China. .,State Key Laboratory of CAD and CG, Zhejiang University, Hangzhou, People's Republic of China.
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Sevcencu C, Pennisi CP, Yoshida K, Gregersen H. Simultaneous monitoring of cellular depolarization and contraction: a new method to investigate excitability and contractility in isolated smooth muscle cells. Am J Physiol Gastrointest Liver Physiol 2008; 294:G648-54. [PMID: 18187522 DOI: 10.1152/ajpgi.00040.2007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The present experiments were performed to establish a method for simultaneous monitoring of excitation and contraction in isolated smooth muscle cells. The smooth muscle cells were dissociated from the colons of Wistar rats by enzymatic digestion. All the experiments were performed on mixtures of circular and longitudinal cells. In a first set of experiments, focal extracellular potentials (FEPs) and transmembrane action potentials (APs) were simultaneously recorded from the cells by use of extracellular and intracellular pipettes, respectively. In a second set of experiments, cellular contraction induced by chemical stimulation was monitored simultaneous with the FEP recordings. The FEPs had spike and plateau amplitudes of 44.5 +/- 2.3 and 8.9 +/- 0.7 mV, respectively, and reproduced the general morphology of gastrointestinal APs. The parallel mechanical measurements from the rat colonic cells showed that they shortened with an average peak contraction of 8.8 +/- 1.4 microm and an average contraction velocity of 8.2 +/- 0.9 microm/s, to develop an average peak force of 1.2 +/- 0.2 microN, and generated an average peak power of 36 +/- 15 pW. Simultaneous monitoring of FEPs and cellular contraction demonstrates correlations between the electrical and mechanical events taking place in the investigated cells.
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Affiliation(s)
- Cristian Sevcencu
- Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
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Klauke N, Smith GL, Cooper J. Extracellular recordings of field potentials from single cardiomyocytes. Biophys J 2006; 91:2543-51. [PMID: 16844752 PMCID: PMC1562398 DOI: 10.1529/biophysj.106.085183] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Open microfluidic channels were used to separate the extracellular space around a cardiomyocyte into three compartments: the cell ends and a central partition (insulating gap). The microchannels were filled with buffer solution and overlaid with paraffin oil, thus forming the cavities for the cell ends. The central part of the cardiomyocyte rested on the partition between two adjacent microchannels and was entirely surrounded by the paraffin oil. This arrangement increased the extracellular electrical resistance to > 20 MOmega and facilitated the recording of the time course of the change in extracellular voltage and current during subthreshold and suprathreshold stimuli. The waveform of the extracellular current and voltage in response to an extracellular depolarizing stimulus comprised an initial monophasic signal followed by a biphasic signal with a delay of 2-15 ms. The latter was associated with a transient contraction and therefore caused by an action potential. The biphasic signal became monophasic after the depolarization of one cell end by raised extracellular [K+]. This form of differential recording revealed the repolarization phase of the action potential. At rest, the sarcomere length within the gap was 12% +/- 4.8% longer than outside the gap, but intracellular Ca2+ transients occurred to the same extent as that observed in the outer pools. This data demonstrate the feasibility of the use of a microfluidic bath design to limit the extracellular resistance between two ends of an isolated cardiomyocyte.
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Affiliation(s)
- Norbert Klauke
- Department of Electronics, University of Glasgow, Glasgow G12 8LT, United Kingdom.
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Riemer TL, Tung L. Stretch-induced excitation and action potential changes of single cardiac cells. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2003; 82:97-110. [PMID: 12732271 DOI: 10.1016/s0079-6107(03)00008-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mechanoelectric coupling (MEC) has been studied extensively in the heart at the tissue and organ levels, but to only a limited extent in single cells because of the technical challenges. New results are presented in which MEC was studied in 57 single frog ventricular myocytes that were held on both ends by glass holding pipettes. Axial stretch was applied either by displacement of the pipettes, or by a glass fiber around which the cell was wrapped, that was displaced in a pulsatile or sinusoidal fashion. Electrical activity of the cell was monitored either by active contraction, by intracellular action potentials, or by focal extracellular potentials. Of more than 350 stretches applied to 57 cells with amplitudes ranging from 3% to 35%, only 4 cases of mechanically induced stimulation were observed. In 252 stretches applied to 32 cells in which action potential duration (APD) was measured, no change >20% was observed, except in 3 cells in which APD increased by >100%, and in 2 cells with extended triggered activity. Thus, in contrast to studies in intact tissue, single frog ventricular myocytes are generally insensitive to direct axial stretch. However, robust mechanosensitive responses were observed in 7 of 57 ( approximately 12%) cells. The results of other single cell studies are reviewed, and the significance of differences in tissue-level and single cell results is discussed.
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Affiliation(s)
- Tara L Riemer
- Department of Biomedical Engineering, The Johns Hopkins University, 720 Rutland Avenue, Baltimore, MD 21205, USA
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