title: Therapeutic response to pramipexole in a patient with multiple system atrophy with predominant parkinsonism: positron emission tomography and pharmacokinetic assessments.
abstract: Multiple system atrophy with predominant parkinsonism (MSA-P) usually shows poor responsiveness to dopaminergic medications. We herein describe a patient with MSA-P who exhibited a good response to pramipexole but not to an ordinary dose of L-dopa. Positron emission tomography (PET) displayed severely impaired presynaptic dopaminergic availability and relatively preserved postsynaptic D2 receptor binding capacity. The pharmacokinetic analyses demonstrated relatively low bioavailability for L-dopa and adequate plasma levels of pramipexole, even at baseline, on a stable daily dose. The PET features and pharmacokinetic differences between L-dopa and pramipexole indicate the presence of unique therapeutic responses to dopaminergic medications in the patient.
authors.affiliation: Department of Neurology, Nippon Medical School, Japan. ueda@nms.ac.jp
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ueda
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Nakajima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nagayama
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nishiyama
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishii
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Katayama
mesh_terms: D000978:Antiparkinson Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D052160:Benzothiazoles / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D001921:Brain / Q000473:pathology; D015897:Comorbidity; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007980:Levodopa / Q000493:pharmacokinetics / Q000627:therapeutic use; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000453:epidemiology; D020734:Parkinsonian Disorders / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000453:epidemiology; D049268:Positron-Emission Tomography; D000077487:Pramipexole; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents; D052160:Benzothiazoles; D007980:Levodopa; D000077487:Pramipexole