[Comparison between the effects of L-dopa, prodipine and amantadine on the serum and CSF amino acid levels in Parkinson's disease (author's transl)].

Patients with Parkinson's disease were treated with different antiparkinsonian drugs and the amino acid levels in serum and cerebrospinal fluid were determined. Results obtained in 43 patients (L-dopa [26]; prodipine [6]; amantadine [11]) are reported. All drugs investigated produced an increase in amino acids in serum and in CSF, this enhancement being most pronounced for neutral, long-chain amino acids. Amantadine, however, showed this effect for a short period, only. Our results lead us to assume that this increased pool of amino acids in the CSF facilities the biosynthesis of amines with transmitter function from their precursor amino acids.