Astrocytes and microglia in the substantia nigra and caudate-putamen in Parkinson's disease

There is evidence that astrocytes and microglia can release agents which might have a protective effect on damaged neurons. However the associations of glia with dopaminergic neurons in Parkinson's disease are not defined. Our studies showed that in post mortem parkinsonian nigra healthy neuronal somata were enveloped by astrocyte processes but these withdrew from fragmenting neurons and amoeboid microglia occupied the vacated peri-somal space. Thus, during the course of the disease both classes of glia are appropriately sited to release protective molecules onto failing neurons, but this may be inadequate for their long-term survival.