The present invention pertains to a method for screening a compound useful in reducing astroglial edema, said method comprising: (i) providing a compound (ii) bringing said compound in contact with an astrocyte and (iii) determining the cAMP level in said astrocyte contacted with said compound wherein said compound is identified as a compound useful in reducing astroglial edema, if the cAMP level in the astrocyte increases after contact. The present invention further pertains to an agent elevating the cAMP level in astrocytes for use in reducing astroglial edema.