CEREBROSPINAL-FLUID OF PARKINSONS-DISEASE PATIENTS INHIBITS THE GROWTH AND FUNCTION OF DOPAMINERGIC-NEURONS IN CULTURE

We report the possible existence of an inhibitory factor in the CSF of Parkinson's disease patients that inhibits the function and growth of dopaminergic neurons in rat mesencephalic culture. After 40 hours' ex posure to the <10 kd fraction of CSF from PD patients, the high-affini ty dopamine uptake was 66% of that of cultures exposed to CSF from con trols. However, the number of dopaminergic neurons remained unchanged at this time. After 90 hours' exposure to the <10 kd fraction of CSF f rom PD patients, the number of dopaminergic neurons decreased to 10% o f that in cultures exposed to CSF from controls, and the size of the r emaining dopaminergic neurons in the culture became smaller. This inhi bitory factor did not affect the growth of other types of neurons. The chemical nature of this inhibitory factor is under investigation.