Simulation of Electrical Interaction of Cardiac Cells

Heppner, D. B.; Plonsey, Robert

doi:10.1016/s0006-3495(70)86352-4

Cited by 66 publications

(18 citation statements)

References 6 publications

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“…The value he calculated for specific disc resistance (3 ~ cm 2) compares very well with that predicted by Woodbury and Crill (1961) on the basis of a potential field analysis of the gap between the membrane regions forming the intercalated disc. Heppner and Plonsey (1970) confirmed their results. Similar values were found by Tanaka and Sasaki (1966) and Spira (1971).…”

supporting

confidence: 81%

Electrotonic spread of current in monolayer cultures of neonatal rat heart cells

Jongsma

Rijn

1972

J. Membrain Biol.

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The passive electrical properties of neonatal rat heart cells grown in monolayer cultures were determined. Hyperpolarizing current pulses were injected through one microelectrode via an active bridge circuit. Membrane voltage displacements caused by the injected current pulses were measured at various distances from the first with a second microelectrode. Using a modified least-squares method the experimental results were fitted to a Bessel function, which is the steady-state solution of the differential equation describing the relation between membrane voltage caused by current injection and interelectrode distance in a very large and very thin plane cell. Best fit was obtained with a space constant of 360 μm and an internal resistivity of 500 Ω cm. From these figures, specific membrane resistance was calculated to be 1,300 Ω cm(2), assuming all current to leave through the upper surface of the monolayer.The time constant of the membrane was measured from the time course of the current-induced membrane voltage displacements. From its value of 1.7 msec a membrane capacity of 1.3 μF/cm(2) was calculated.From these results and some literature data on nexus distribution (A. W. Spira,J. Ultrastruct. Res. 34:409, 1971) specific nexus resistance was calculated to range between 0.25 and 1.25 Ω cm(2), depending on the amount of folding of the intercalated discs. The results suggest that spread of activation in monolayer cultures of heart cells by means of local circuit currents is very likely.

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supporting

confidence: 81%

Electrotonic spread of current in monolayer cultures of neonatal rat heart cells

Jongsma

Rijn

1972

J. Membrain Biol.

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“…Several investigators adopted a segmented model consisting of two cellular domains with excitable membranes connected by a single resistance. 32 - 34 Lieberman et aJ, 33 using linear cables as cellular domains, reported a ratio of TJR^ of 6 as an upper limit for successful impulse transfer. Employing single cells as cellular domains, Joyner and van Capelle 36 found that the requirement of successful transmission was met with ratios of r^R;,, in the range of 1.7-10.…”

Section: Impulse Transfer and Nexal Resistancementioning

confidence: 99%

Action potential transfer in cell pairs isolated from adult rat and guinea pig ventricles.

Weingart

Maurer

1988

Circulation Research

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An enzymatic procedure was used to obtain ventricular cells from adult rat and guinea pig hearts. Isolated pairs of cells were selected to study the action potential transfer from cell to cell and determine the resistance of the nexal membrane, rn. For this purpose, each cell of a cell pair was connected to a patch pipette so as to enable whole-cell, tight-seal recording. Normal impulse transmission was observed when rn ranged from 5-265 M omega. In these cases, the action potential in both cells occurred virtually simultaneously. An occasional failure in action potential transfer was seen in cell pairs whose rn had increased to 155-375 M omega. In these cases, the impulse transfer across the nexal membrane occurred with considerable delay. Impulse transfer was completely blocked once rn was larger than 780 M omega. Assuming a single connexon conductance of 100 pS, this would mean that more than 13 connexons are necessary to allow impulse transfer from cell to cell. Two single myocytes, gently pushed together, neither showed electrotonic interaction nor impulse transfer, thus rendering unlikely the possibility of an ephaptic signal transmission.

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“…The length constant A, i.e., the distance over which the subthreshold voltage pulse decreases by a factor e, differs in various parts of the heart (Table I) but is generally reported in the range 0.5-1.5 mm (Spira, 1971 ;Weidmann, 1970;Bonke, 1973a,b;Seyama, 1976). When combined with measurements of junctional area, the junctional resistance between myocardial cells has been estimated at less than 5 Ω · c m 2 (Woodbury and Crill, 1961;Heppner and Plonsey, 1970;Matter, 1973). Measured values of longitudinal resistivity in myocardial fibers (Table I, K,) generally fall in the range of 100-500 Ω · cm.…”

Section: Cell Junctionsmentioning

confidence: 99%