Basic research on dopamine in Parkinson's disease and the discovery of the nigrostriatal dopamine pathway: the view of an eyewitness.

The article recapitulates some of the historical facts that led up to the recognition of dopamine (DA) as a biologically active substance in the brain and its crucial role in Parkinson's disease (PD). Three events to which the writer has been an eyewitness are specially highlighted and placed in their proper historical perspective: (1) the discovery of the striatal DA deficit in the PD brain; (2) the development of the DA replacement treatment with L-dopa, and (3) the 'birth' of the nigrostriatal DA pathway. The opposition to the new observations and their unexpected and far-reaching consequences will be illustrated by briefly discussing the strongly negative opinions expressed by some famous brain scientists of the day about the relationship between the substantia nigra, PD, and the DA-containing nigrostriatal fiber connection.