Study type: Medical/biological study (experimental study)

Analysis of the effects of pulsed microwaves on cardiac activity. med./bio.

Published in: Bioelectrochem Bioenerg 1993; 30: 303-311

Aim of study (acc. to editor)

This study was conducted to evaluate the effects of pulsed microwaves exposure on isolated hearts of chicken embryos for two different physiological conditions: regular and irregular heartbeat.

Background/further details

The experiments were carried out on isolated living hearts of 8-9 days old chicken embryos.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.45 GHz
Modulation type: pulsed
Exposure duration: repeated exposures in the order of 1 min

Exposure 1

Main characteristics
Frequency 2.45 GHz
Type
Exposure duration repeated exposures in the order of 1 min
Modulation
Modulation type pulsed
Duty cycle 10 %
Additional info

pulse rates of 1-3 Hz

Exposure setup
Exposure source
  • coaxial MW radiator
Chamber A pre-oxygenated avian Ringer's solution kept at 37°C was perfused in the sample holder.
Setup The heart was placed in the sample holder with its main axis perpendicular to the EF in the max. field area and irradiated from the bottom by a tapered open coaxial section.
Additional info In cases of regular heartbeat, the MW pulse rate was set a little higher than the unperturbed natural heart rate. In cases of arrhythmia, a constant pulse rate was selected within physiological limits (1-3 Hz). Usually, the beating heart allowed to conduct tests for about 6 h.
Parameters
Measurand Value Type Method Mass Remarks
power density 3 mW/cm² peak value - - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • before exposure
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

An appropriate pulse repetition rate caused regularization of irregular heartbeat. During regular heartbeat, an increase of pulse repetition rate similarly increased the heartbeat frequency, until an irregular heartbeat appeared. By applying microwaves, when an arrhythmia occured, a regular heartbeat appeared after a few seconds.
These results suggest a mechanism for the synchronization effect induced by pulse-modulated microwaves on heart cells.

Study character:

Study funded by

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