Apomorphine effect on pain threshold in Parkinson's disease: a clinical and positron emission tomography study.
Patients with Parkinson's disease (PD) frequently experience pain that could be in part due to central modification of nociception. In this randomized controlled double blind study, we compared the effect of apomorphine versus placebo on pain thresholds and pain-induced cerebral activity in 25 patients with PD. Subjective pain threshold (using thermal stimulation, thermotest), objective pain threshold (nociceptive flexion reflex), and cerebral activity (H(2)(15)O PET) during noxious and innocuous stimulations were performed. Neither subjective nor objective pain thresholds nor pain activation profile were modified by apomorphine compared with placebo in 25 PD patients. Apomorphine has no effect on pain processing in PD. We suggest that other monoamine systems than dopaminergic system could be involved.
Inserm, Imagerie cérébrale et handicaps neurologiques, Toulouse, France. estelle.dellapina@inserm.fr
Estelle
E
Dellapina
Angélique
A
Gerdelat-Mas
Fabienne
F
Ory-Magne
Laure
L
Pourcel
Monique
M
Galitzky
Fabienne
F
Calvas
Marion
M
Simonetta-Moreau
Claire
C
Thalamas
Pierre
P
Payoux
Christine
C
Brefel-Courbon
D000368:Aged; D000978:Antiparkinson Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001058:Apomorphine / Q000494:pharmacology* / Q000627:therapeutic use; D002540:Cerebral Cortex / Q000000981:diagnostic imaging; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000175:diagnosis / Q000209:etiology; D010103:Oxygen Isotopes; D017288:Pain Threshold / Q000187:drug effects*; D010300:Parkinson Disease / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D049268:Positron-Emission Tomography / Q000379:methods
D000978:Antiparkinson Agents; D010103:Oxygen Isotopes; D001058:Apomorphine