Role of Stretch-Activated Channels in Stretch-Induced Changes of Electrical Activity in Rat Atrial Myocytes
The Korean Journal of Physiology and Pharmacology
;
: 33-41, 2004.
Article
in English
| WPRIM
| ID: wpr-728505
ABSTRACT
We developed a cardiac cell model to explain the phenomenon of mechano-electric feedback (MEF), based on the experimental data with rat atrial myocytes. It incorporated the activity of ion channels, pumps, exchangers, and changes of intracellular ion concentration. Changes in membrane excitability and Ca2+ transients could then be calculated. In the model, the major ion channels responsible for the stretch-induced changes in electrical activity were the stretch-activated channels (SACs). The relationship between the extent of stretch and activation of SACs was formulated based on the experimental findings. Then, the effects of mechanical stretch on the electrical activity were reproduced. The shape of the action potential (AP) was significantly changed by stretch in the model simulation. The duration was decreased at initial fast phase of repolarization (AP duration at 20% repolarization level from 3.7 to 2.5 ms) and increased at late slow phase of repolarization (AP duration at 90% repolarization level from 62 to 178 ms). The resting potential was depolarized from -75 to -61 mV. This mathematical model of SACs may quantitatively predict changes in cardiomyocytes by mechanical stretch.
Full text:
Available
Index:
WPRIM (Western Pacific)
Main subject:
Action Potentials
/
Muscle Cells
/
Myocytes, Cardiac
/
Ion Channels
/
Membrane Potentials
/
Membranes
/
Models, Theoretical
Type of study:
Prognostic study
Limits:
Animals
Language:
English
Journal:
The Korean Journal of Physiology and Pharmacology
Year:
2004
Type:
Article
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