Abstract
The effects of a pyridinium metabolite (HPP +) derived from haloperidol (HP) on in vivo tyrosine hydroxylation was evaluated in freely moving rats. As an index of the in vivo activity of tyrosine hydroxylase (TH), the rat striatum was perfused with NSD-1015, and extracellular 3,4-dihydroxyphenylalanine (DOPA) levels were measured. HPP + (1 mM) gradually reduced tyrosine hydroxylation to 30% of the basal level, although the effect was less potent than 1-methyl-4-phenylpyridinium ion (MPP +). On the contrary, HPP + at a 0.1 mM dose decreased in 5-hydroxyindoleacetic acid (5-HIAA) level, but did not affect dopamine metabolites. The present study revealed that HPP + irreversible inhibited in vivo tyrosine hydroxylation by the same manner of MPP +. However, the neurotoxic effects of HPP + in vivo would be selective for serotonergic over dopaminergic neurons, which distinguishes the toxic profile of this compound compared to that of MPP +.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
