Medical/biological study (experimental study)

Synaptosomal acetylcholinesterase activity variation pattern in the presence of electromagnetic fields med./bio.

By: Afrasiabi A, Riazi GH, Abbasi S, Dadras A, Ghalandari B, Seidkhani H, Modaresi SM, Masoudian N, Amani A, Ahmadian S

Published in: Int J Biol Macromol 2014; 65: 8-15

The enzyme acetylcholinesterase controls the concentration of acetylcholine in the synaptic clefts by hydrolizing acetylcholin to choline and acetate. Cholinergic synapses are involved in important brain functions such as learning, memory and cognition. An acetylcholinesterase dysfunction could lead to cognitive disorders.
The effect of different frequencies, exposure times and magnetic field intensities on the enzyme activity of acetylcholinesterase was tested. Data were analyzed by a software to predict acetylcholinesterase acticity pattern.

Exposure	Parameters
Exposure 1: 50–230 Hz Exposure duration: up to 120 minutes (15, 30, 45, 60, 90, 120 minutes)	magnetic flux density: 0.3 mT minimum magnetic flux density: 0.5 mT magnetic flux density: 0.7 mT magnetic flux density: 0.9 mT magnetic flux density: 1.1 mT magnetic flux density: 1.3 mT magnetic flux density: 1.5 mT magnetic flux density: 1.7 mT maximum

Exposure source	Helmholtz coils
Setup	tube of synaptosomal suspension was placed in the area of the two parallel coils with 35 cm distance and 35 cm internal diameter made of 1000 turns of coated 1.3 mm copper wire (magnetic field lines ran vertically), the device was supplied by a power generator, and frequency and intensity of magnetic field were monitored by a sensor connected to a digital multimeter and oscilloscope, temperature fluctuations were negliable
Sham exposure	A sham exposure was conducted.

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	0.3 mT	minimum	measured	-	-
magnetic flux density	0.5 mT	-	measured	-	-
magnetic flux density	0.7 mT	-	measured	-	-
magnetic flux density	0.9 mT	-	measured	-	-
magnetic flux density	1.1 mT	-	measured	-	-
magnetic flux density	1.3 mT	-	measured	-	-
magnetic flux density	1.5 mT	-	measured	-	-
magnetic flux density	1.7 mT	maximum	measured	-	-

Exposed system:

Investigated system:

Time of investigation:

The enzyme activity of the acetylcholinesterase changed according to the intensity and the frequency of the magnetic field. In the intensity range from 1.2 mT to 1.7 mT and frequency range from 50 Hz to 90 Hz, the enzyme activity was significantly decreased compared to the unexposed control. However, in the intensity range from 0.3 mT to 0.6 mT and frequency range from 50 Hz to 90 Hz, as well as in the intensity range from 0.8 mT to 1.2 mT and frequency range from 150 Hz to 230 Hz, the enzyme activity was significantly increased in comparison to the control. The exposure duration had no significant effect.
The authors conclude that exposure to extremely low frequency magnetic fields could be a promising tool in the treatment of cholinergic disorders.

Study character:

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