Abstract

Clinical and neuropharmacological evidence indicates the involvement of dopaminergic mechanisms in Parkinson's disease and schizophrenia, as well as in iatrogenic Parkinsonism and drug-induced schizophrenia-like syndrome. The evidence hitherto presented stresses the existence of a reversed relationship between Parkinson's disease and schizophrenia and implicates the possibility that dysfunction of dopamine-receptors may be a central phenomenon in both diseases. In view of the recent demonstration of two separate dopamine-receptors, it is postulated that a striatal receptor blockade may cause Parkinson's disease, whereas a limbic receptor blockade may result in schizophrenia. The recent discovery that several autoimmune diseases, such as myasthenia gravis, are the result of an immunopharmacological block at receptor sites, together with several observations of immunological disorders in Parkinson's disease and schizophrenia, suggests the possibility that certain types of Parkinson's disease and schizophrenia might be the consequence of an autoimmune blockade of striatal or limbic dopamine-receptors, respectively.