To study the effects of extremely low frequency electromagnetic fields of 75 Hz on different membrane-associated enzymes.
The choice was done among integral membrane proteins (calcium-ATPase, sodium potassium ATPase, succinate dehydrogenase), peripheral membrane proteins (photoreceptor phosphodiesterase 6), and lipid-linked proteins (alkaline phosphatase, acetylcholinesterase).
| Exposure | Parameters |
|---|---|
|
Exposure 1:
75 Hz
Modulation type:
pulsed
Exposure duration:
continuous for 1, 2, 3, 5, 10, 20 and/or 30 min
|
|
|
Exposure 2:
75 Hz
Modulation type:
pulsed
Exposure duration:
continuous for 10 min
|
- |
| Frequency | 75 Hz |
|---|---|
| Type | |
| Waveform | |
| Exposure duration | continuous for 1, 2, 3, 5, 10, 20 and/or 30 min |
| Modulation type | pulsed |
|---|---|
| Additional info |
Square wave with a duty cycle of 10% |
| Exposure source | |
|---|---|
| Setup | The sample were placed in the center of the coils. Control were run in the same experimental conditions but in the absence of magnetic field. |
| Additional info | Different magnetic fields were obtained by changing the distance between the coils. |
| Measurand | Value | Type | Method | Mass | Remarks |
|---|---|---|---|---|---|
| magnetic flux density | 2.5 mT | - | measured | - | at a distance of 3 cm between the coils |
| Frequency | 75 Hz |
|---|---|
| Type | |
| Waveform | |
| Exposure duration | continuous for 10 min |
| Modulation type | pulsed |
|---|---|
| Additional info |
Square wave with a duty cycle of 10% |
| Exposure source |
|
|---|
No parameters are specified for this exposure.
The activities of three enzymes out of seven exposed to the electromagnetic field decreased approximately of about 54-61 % with field amplitudes above a threshold of 73-151 µT depending on the enzyme. The same field had no effect on the activities of either integral membrane enzymes such as calcium-ATPase, sodium potassium ATPase, succinate dehydrogenase or peripheral membrane enzymes (photoreceptor phosphodiesterase 6).
The decrease in enzyme activity of the field-sensitive enzymes was independent of the time of permanence in the electromagnetic field and was completely reversible. When these enzymes were solubilized with Triton, no effect of the field was revealed on the enzyme activity, suggesting the crucial role of the membrane in determining the conditions for enzyme inactivation.
This website uses cookies to provide you the best browsing experience. By continuing to use this website you accept our use of cookies.
