The antiparkinsonian drug budipine binds to NMDA and sigma receptors in postmortem human brain tissue.

We have estimated the affinity of the antiparkinsonian drug budipine to the PCP binding site of the NMDA receptor and to sigma 1 binding sites in membranes from postmortem human brain frontal cortex. The affinity of budipine to both binding sites is in a concentration range that may be reached under therapeutic conditions (Ki-values of about 12 and 2 microM at the PCP and sigma 1 binding site, respectively). Interactions with NMDA receptors as well as sigma 1 binding sites may contribute to the antiparkinsonian effects of budipine.