[Neurobiologic and pharmacologic studies on the pathogenesis of Parkinson disease]

Parkinson's disease is characterized especially by a degeneration of pigmented brain regions, like substantia nigra. These changes are accompanied by a variety of biochemical disturbances of dopaminergic and noradrenergic systems. Also the reduction of serotonin can be related to degenerative processes occurring in subareas of the raphe. Furthermore amino acid transmitters like GABA and a variety of peptidergic neuromodulators are changed. Additional cholinergic hypofunction due to degeneration of the nucleus basalis Meynert is able to impair the quality of life due to loss of intellectual capacity. A variety of biochemical mechanisms compensate for a long time the progression of neuronal loss. Modern treatment strategies (combined L-dopa therapy, dopaminergic agonists, MAO-B inhibitors, amantadine) are able to substitute the deficiency especially of the catecholamines. For the development of more causal therapies, a new animal model has been developed 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes parkinsonism after peripheral administration and leads to denervation of the dopaminergic nigrostriatal system. It is the hope that this new model, which is described here in detail, will lead to decisive data underlying the cause of Parkinson's disease.