1. The antiparkinsonian drugs budipine and biperiden are use-dependent (uncompetitive) NMDA receptor antagonists
- Author
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Rolf Jackisch, Georg Hertting, Thomas J. Feuerstein, Willi Sauermann, and Alexander Kruchen
- Subjects
Caudate nucleus ,Budipine ,Pharmacology ,In Vitro Techniques ,Binding, Competitive ,Receptors, N-Methyl-D-Aspartate ,Biperiden ,Antiparkinson Agents ,Piperidines ,medicine ,Animals ,Chemistry ,Antagonist ,Acetylcholine ,Mechanism of action ,Competitive antagonist ,NMDA receptor ,Rabbits ,medicine.symptom ,Caudate Nucleus ,Dizocilpine Maleate ,Software ,medicine.drug - Abstract
N-Methyl-D-aspartate- (NMDA-) evoked [3H]acetylcholine release in rabbit caudate nucleus slices was inhibited by the antiparkinsonian drugs budipine (1-tert-butyl-4,4-diphenylpiperidine) and biperiden (1-bicyclo[2.2.1.]hept-5-en-2-yl-1-phenyl-3-piperidino propanol) yielding functional Ki values of 4.6 and 8.8 microM. In contrast to the competitive antagonist 2-amino-5-phosphonopentaonate, budipine and biperidene significantly reduced both the apparent KD and the Emax value of NMDA. Moreover, they displaced [3H]MK-801 specifically bound to membranes of the same tissue, although with low affinity (IC50: 38 and 92 microM). It is concluded that budipine and biperiden are use-dependent (uncompetitive) antagonists at the NMDA receptor, binding to the receptor-linked ion channel, but probably not to the MK-801 binding site. NMDA antagonism may contribute to the antiparkinsonian effects of budipine.
- Published
- 1994