In order to confirm the data of previous studies (see publication 145 and publication 9725) under more controlled conditions, rats were exposed to static magnetic fields of 4 to 19.4 Tesla in a 189 mm bore, 20 Tesla resistive magnet.
By using a resistive magnet (instead of superconducting NMR magnets as in the previous studies), field strengths could be arbitrary varied from -19.4 to 19.4 Tesla.
| Exposure | Parameters |
|---|---|
|
Exposure 1:
Exposure duration:
continuous for 30 min
|
|
|
Exposure 2:
Exposure duration:
repeated daily exposure, 30 min/day for 3 consecutive days
|
|
| Frequency | |
|---|---|
| Type | |
| Exposure duration | continuous for 30 min |
| Exposure source | |
|---|---|
| Setup | Rats were placed individually and immobilized into a Plexiglas restraining tube (56 mm inner diameter, 64 mm outer diameter). Four tubes were suspended vertically in the magnet so that the magnetic field lines were parallel. |
| Sham exposure | A sham exposure was conducted. |
| Additional info | Rats were also exposed (14 T) or sham exposed with the magnetic field lines running parallel to the dorsal ventral axis by restraining the rats in a horizontal position in the core of the magnet. |
| Measurand | Value | Type | Method | Mass | Remarks |
|---|---|---|---|---|---|
| magnetic flux density | 19.4 T | maximum | - | - | 17 T, 14 T, 7 T or 4 T |
| Frequency | |
|---|---|
| Type | |
| Exposure duration | repeated daily exposure, 30 min/day for 3 consecutive days |
| Measurand | Value | Type | Method | Mass | Remarks |
|---|---|---|---|---|---|
| magnetic flux density | 14 T | - | - | - | or -14 T (reverse polarity) |
Rearing (one or both forepaws on the side of the cage) was suppressed after exposure to 4 Tesla and above; circling was found after 7 Tesla and above. Conditioned taste aversion (see publication 145) was acquired after 14 Tesla and above.
The effects were dependent on orientation in the field: Exposure to +14 Tesla induced counter-clockwise circling, while exposure to -14 Tesla induced clockwise circling. Exposure with the rostral-caudal axis of the animal perpendicular to the magnetic field produced an attenuated behavioral response compared to exposure with the rostral-caudal axis parallel to the field.
These findings in a single resistive magnet confirm and extend the authors' earlier results using multiple superconducting magnets. The effects of exposure to 4 Tesla are clinically relevant, as 4 Tesla magnetic fields are commonly used in functional MRI assays.
This website uses cookies to provide you the best browsing experience. By continuing to use this website you accept our use of cookies.
