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Study of Human Action Potential
Kristina Pantelić, Third Belgrade Grammar School, III grade
Radnička Street 40, 11090, Belgrade
Introduction itself, that is its' changes, are examined
through the change in charge on a capacitor.
The goal of the research is modelling By changing the capacitor's charge capacity,
of action potential, using which the influence the thickness of myelin sheath is also
of various parameters on neuron's functioning changed. R 1 has a variable resistance, it
can be studied. Each living cell's stabilizes the circuit and it is a resistance
characteristic is the existence of membrane which speaks of other ions which could
potential. The value of the resting membrane appear. R 5 and R 6 resistances are other
potential is -60mV, and the inside of the cell channels.
has a more negative charge than its' outside.
When some chemical, mechanical or Results
electrical stimulant affects the membrane of
excitable cell, the membrane potential is
being changed. The change which leads to a
change in membrane potential up to +45mV
is called action potential.
Material and Methods Photo 2. The Transfer of Electrical Signal
through the Membrane
Biological equivalent of action
potential can be presented using electrical Conclusion
circuit which is composed of simple
+
components, because they have the same Na has the biggest influence on the
characteristics and can be mathematically transfer of action potential, biologically
defined by using similar (in most cases, same) presented as the R 2 resistor. The created
equations and relations. A program package model is a simple model. Therefore, realistic
called PSpice was being used, within which it data cannot be gotten, but with the use of an
was being operated* in a program called advanced model, far more parameters would
OrCAD Capture, used for making electrical be considered.
circuits.
Literature
1. Mahdavi S, Rezaei-Tavirani M, The
Different Mechanisms of Action
Potential Propagation in the Heart,
Iranian Journal of Pharmaceutical
Research (2007) 6 (1): 51-56
2. Ramasamy L, Sperelakis N.
Repolarization of the action potential
enabled by Na channel deactivation
+
Photo 1. Electrical Circuit Used in the in PSpice simulation of cardiac
Simulation Alternating sources in a circuit muscle propagation, BioMedical
represent impulses Engineering OnLine (2005)
Each ion channel and the myelin
sheath are wires which are modeled with
resistor (R). The resistor R 2 represents ion
+
channel for Na which affects the formation
of action potential the most. The membrane
