Add to ORKGOne of the problems in biomedical research is to understand the relationship between a drug-evoked gross reaction in vivo and different effects measured in vitro. The TET induced brain edema that has been the subject of our studies as reported in this thesis is an example of this statement. The TET edema itself has been localized predominantly in the white matter of the central nervous system and is demonstrated by chemical methods and electron microscopy. The development of the edema can be described chemically as an increase of the sodium and water content in the central white matter; electronmicroscopical studies reveal large vacuoles at the position of the intraperiod line between the lamellae of the myelin-sheaths of the white matter.....