Study type: Medical/biological study (experimental study)

Enhancement of Anticancer Drug Delivery to the Brain by Microwave Induced Hyperthermia. med./bio.

Published in: Bioelectrochem Bioenerg 1998; 47 (2): 259-264

Aim of study (acc. to author)

To examine the effect of selective microwave hyperthermia on the transport of MTX (methotrexate) across blood-brain barrier. MTX is a prescribed antifolate in cancer chemotherapy for a variety of neoplasms. MTX concentration in brain tissue with or without microwave hyperthermia was compared. Animals received MTX immediatelay, 15, or 45 min following microwave hyperthermia treatment.



Exposure Parameters
Exposure 1: 2.45 GHz
Modulation type: CW
Exposure duration: continuous for 20 min

Exposure 1

Main characteristics
Frequency 2.45 GHz
Exposure duration continuous for 20 min
Modulation type CW
Exposure setup
Exposure source
  • 7 mm circular dielectrically loaded coaxial applicator.
Setup Rats were immobilized in a streotaxic head holder with the MW applicator placed on top of the holder in such a way that the left hemisphere of the brain was exposed.

No parameters are specified for this exposure.

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The average uptake at the posterior left hemisphere was 2.25 +/- 0.43, 10.40 +/- 2.59, and 17.23 +/- 1.13 µg of MTX per gram of brain tissue for 50, 100, and 200 mg/kg doses, respectively. Brains of rats injected 45 min after exposure were free of MTX. Rats euthanized 15 min post-irradiation had an average midbrain MTX concentration of 2.5 +/- 0.46 µg of tissue. These data indicate that MTX uptake is significantly increased in brains subjected to noninvasive microwave hyperthermia treatment. Furthermore, the increase is reversible within 45 min post-exposure.

Study character:

Study funded by