News from substantia nigra neuromelanin

Neuromelanin (NM) is thought to be a polymer especially of catecholaminergic neurons in the brain. NM of dopaminergic neurons of the substantia nigra pars compacta (SNpc) appears as “black“ while NM of the noradrenergic locus coeruleus (LC) shows “blue“ colour. In general, NM in the human SN is seen first at an age of 3–5 years of life and accumulates further up to an age of about 20 years. It is not synthesized in rodents. In many textbooks NM is regarded as “garbish“, a spill-over of dopamine/L-DOPA being responsible for this autoxidation product. But is it so? There are evidences to suggest that it does not i…