TOWARDS AND IMPROVED SURVIVAL OF RAT-BRAIN NEURONS IN CULTURE BY CEREBROSPINAL-FLUID OF PATIENTS WITH SENILE DEMENTIA OF ALZHEIMERS TYPE

Neuronal cell survival was investigated in rat brain cortical cultures in the presence of increasing concentrations of human brain extracts or cerebrospinal fluid (CSF) from control and Senile Dementia of Alzhe imer's type (SDAT) patients. Using hippocampal brain extracts, convert ed 4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) wa s compared to the content of the neuronal marker MAP2 in foetal rat br ain neuronal cultures in order to test converted MTT as a quantitative parameter for neuronal cell survival. A significant correlation was f ound between both parameters. SDAT frontal cortex brain extracts induc ed a two to four-fold increase in neuronal cell survival at 25 to 125 mug protein extract, whereas control brain extracts induced at similar protein concentrations a decline in neuronal cell survival. The enhan ced survival yielded by SDAT brain extracts was fully abolished in the presence of control brain extract. Control CSF concentration-dependen tly increased neuronal cell survival in postnatal rat brain neuronal c ultures independent of the difference in the protein content of CSF sa mples and age of the patients. SDAT CSF also concentration-dependently enhanced neuronal cell survival, however, the effect was more pronoun ced compared to control CSF. These observations are in favour of the h ypothesis that there might be a higher neurotrophic activity in SDAT b rain tissue.