Course detail

Bioelectric Phenomena

FEKT-ABEJAcad. year: 2019/2020

Physical interpretation of electric phenomena in living tissue constitutes a special area of biophysics. The subject ‚Bioelectric phenomena‘ acquaints the students with biophysical basis of the genesis of electric signals on different structural levels , with passive electric properties a of living tissue, and with currently available methods of bioelectric measurements.

Learning outcomes of the course unit

Passing the subject, the student is able:
- to explain genesis of membrane voltage in the living cells applying the known physical laws and to define quantities that appear in the Nernst formula for equilibrium voltages,
- to describe electrical equivalent scheme of the cell,
- to explain origin of action voltages in excitable cells and mechanism of its propagation along cell fibers,
- to describe principles of the methods of measurement of membrane voltage and membrane current,
- to characterize electrical signals recorded on cellular and molecular level and to explain their mutual relations,
- to define the terms “chemical potential’’ and ‘’electrochemical potential’’,
- to describe the relation between the propagated excitation at the level of cell and genesis of electromagnetic field in the surrounding tissue,
- to explain principles of excitation-contraction coupling in muscle cells,
- to describe origin of ECG signal as a result of action voltage propagation in the net of cardiac cells (syncytium),
- to prepare physiological solutions including measurement and adjustment of their pH, to measure tissue impedance and properties of the electrodes.

Prerequisites

Knowledge of biology, mathematics and physics accordant with the subjects of previous bachelor’s study is expected.

Co-requisites

Not applicable.

Recommended optional programme components

Not applicable.

Recommended or required reading

J. Šimurda: Bioelektrické jevy I, CERM Brno, 1995 (CS)
S. Silbernagl, A. Despopoulos: Atlas fyziologie člověka, GRADA Publishing a.s. 2004 (CS)
F. Bezanilla:Electrophysiology and the Molecular Basis of Excitability. (University of California at Los Angeles) Volně dostupné na adrese http://nerve.bsd.uchicago.edu/ (EN)
T. F. Weiss: Cellular Biophysics, Massachusetts Institute of Technology,1996 (vol.2 –ISBN 0-262-23184-0)) (EN)
R.Plonsey: Bioelectric Phenomena. McGraw-Hill, New York, 1969 (EN)
R.Plonsey, R.C. Barr: Bioelectricity: A Quantitative Approach. Plenum Press, New York, 1988 (EN)
J.Šimurda, Bioelektrické jevy, elektronická skripta 2007 (CS)

Planned learning activities and teaching methods

Teaching methods depend on the type of course unit as specified in the article 7 of BUT Rules for Studies and Examinations.

Assesment methods and criteria linked to learning outcomes

Requirements for successful completion of the subject are specified by guarantor’s regulation updated for every academic year.

Language of instruction

Czech

Work placements

Not applicable.

Course curriculum

A. Cellular level
1 Origin and function of electrical signals in living cells (membrane voltage, action voltage in excitable cells, propagation of action voltage, physiological significance of electrical activity)
2 Methods of measurements of membrane voltage and membrane current (electrical contacts with cell interior, technical problems and variants of their solving)
3 Physical bases of bioelectric phenomena:
Resting membrane voltage (model of the cell, electrical equivalent scheme of the cell membrane)
Action voltage (underlying mechanisms, principal components of ionic membrane current, quantitative relation between total ionic current and action voltage configuration, classification of channels from the viewpoint of time and voltage dependence, propagation of action voltage along cellular fibres)
4 Quantitative description of electrical activity of excitable cell (Hodgkin and Huxley equations for squid nerve fibres, solution under current-clamp and voltage-clamp conditions, generalization for other excitable cells, quantitative description of propagation of excitation)
5. Thermodynamic description of bioelectric phenomena (chemical and electrochemical potential, derivation of Nernst equation, Donnan equilibrium, Nernst-Planck equation, constant electrical field model)

B. Molecular level
6 Membrane ionic channels (biological membrane, structure and function of ionic channels,
gating process, drug-channel interactions, measurements of single channel currents, principle of patch clamp method, characteristics of the current recorded on molecular level)
7 Membrane ion transporting carriers (function, Na/K and Na/Ca exchangers)

C. Excitation-contraction coupling (ECC) in muscle cell
8 Structure and function of muscle, differences between types of muscle cells
9 Main structural and functional elements of ECC in cardiac cells and signalling role of Ca ions (quantitative description of transmembrane transport of calcium ions, explanation of frequency dependence of contractions )
10 Molecular processes underlying muscle contraction

D. Tissue and organ level
11 Electromagnetic field as a consequence of action voltage propagation (related clinical diagnostic methods, passive electrical properties of living tissue)
12 Biophysical background of electrocardiography (mechanism and propagation of the wave of excitation in the heart, lead systems, ECG signal, arrhythmias and natural protective mechanisms, equivalent generators of cardiac electrical field)
13 Quantitative description of the electromagnetic field generated by biological sources (application of Maxwell equations, simplifications for cardiac electrical field)

Aims

To teach the students how to apply the knowledge acquired by previous study of physics and mathematics to understand mechanisms underlying origin of electric signals in living organisms

Specification of controlled education, way of implementation and compensation for absences

Extent and forms are specified by guarantor’s regulation updated for every academic year.

Classification of course in study plans

  • Programme BTBIO-A Bachelor's

    branch A-BTB , 3. year of study, winter semester, 5 credits, compulsory

  • Programme EEKR-CZV lifelong learning

    branch ET-CZV , 1. year of study, winter semester, 5 credits, compulsory

Type of course unit

 

Lecture

26 hours, optionally

Teacher / Lecturer

Laboratory exercise

26 hours, compulsory

Teacher / Lecturer

eLearning