Apomorphine Effect on Nociceptive Perception in Parkinson's: a Clinical and Imaging Study (APODOUL)

Apomorphine Effect on Nociceptive Perception in Parkinson's: a Clinical and Imaging Study.

Patients suffering from Parkinson's disease (PD) frequently experienced painful sensations. We suppose that painful symptoms could be related to the neurotransmitter deficit of PD. So, we would like to evaluate the involvement of dopaminergic system in nociceptive processing in PD patients. The objectives of this study is to assess and to compare the effect of a dopamine agonist administration on the nociceptive threshold and on the cerebral activity using positrons emission tomography (PET scan) in two groups of PD patients (in 16 painful PD patients and in 16 pain free PD patients). We hypothesise that dopamine agonist could normalise nociceptive threshold and cerebral activity which were both abnormal in PD patients. Moreover, we think that painful PD patients could be more improved by dopamine agonist than pain free PD patients.

Study Overview

• Status: Completed
• Conditions: Parkinson's Disease
• Intervention / Treatment: Drug: apomorphine; Drug: placebo

Detailed Description

Patients suffering from Parkinson's disease (PD) frequently experienced painful sensations. Painful complaints with various description (muscle cramps, painful dystonia, aching, numbness, tingling, burning, vibrating, lancinating) are described and can or cannot be related to motor symptoms. Physiopathology of pain in PD is discussed. It has been suggested that the occurrence of painful symptoms could be in part due to central modification of nociception and basal ganglia damage and the dopaminergic deficit would be expected to eliminate the inhibitory influence on thalamic nociceptive activity. Recently, data have shown that PD patient had a lower nociceptive threshold than healthy volunteers. Our team has reported that levodopa administration normalised this nociceptive threshold and decreased cerebral activity measured with positrons emission tomography (PET- H215O during experimental nociceptive stimulation) in several nociceptive cortical areas which were overactive in PD. These findings suggest that central dopamine system plays an important part in the control of the nociceptive pathways in PD. Nevertheless, in the central nervous system, levodopa could be converted in dopamine but also in noradrenaline modulating noradrenergic system. In order to confirm the involvement of dopaminergic system in nociceptive processing in PD, we would like to assess a specific drug of dopamine system (a dopamine agonist, apomorphine) in PD patients.

The primary objective of this study is to assess the effect of dopamine agonist acute administration versus placebo on the nociceptive subjective threshold in two groups of PD patients (painful PD patients, n =16 and pain free PD patients, n = 16). This is a controlled cross over, double blind, randomised study.

The secondary objectives are to assess and to compare the apomorphine effect on the objective nociceptive threshold (nociceptive flexion reflex) and on the activation of cerebral areas using functional imaging (TEP- H215O) during experimental nociceptive stimulation in the two groups of PD patients.

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Toulouse, France, 31059
    • Service de Neurologie

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients suffering from Parkinson's disease
• PD patients with a Hoehn et Yahr < à 3 (Hoehn et Yahr 1967)
• PD patients treated by dopaminergic drugs (levodopa, dopamine agonist, IMAO-B, ICOMT…)
• Painful PD patients : PD patients suffering from chronic pain (> 3 months) which is related to PD and suggests neuropathic pain
• Pain free PD patients : PD patients without any pain related to PD.

Exclusion Criteria:

• Patients with chronic disease resulting in chronic pain (severe arthosis….)
• PD patients with a Hoehn et Yahr stage > 3 (Hoehn et Yahr 1967)
• Patients with cancer
• Patients who underwent a PET scan in the last three months
• Pregnancy
• Patients with a contra indication of use of apomorphine or domperidone.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: 2; Placebo	Drug: placebo; placebo subcutaneous
Experimental: 1; Apomorphine	Drug: apomorphine; Acute apomorphine subcutaneous 3 mg

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
The primary outcome of this study is subjective nociceptive threshold using thermotest. We determinate thermal nociceptive threshold using a Peltier- based contact temperature stimulation device with a contact thermode.	the primary outcome is measured after acute administration of apomorphine ( after 30 minutes )

Secondary Outcome Measures

Outcome Measure	Time Frame
Objective nociceptive threshold using the nociceptive flexion reflex (RIII) which can be elicited by a nociceptive electrical stimulation to the sural nerve and recorded in the ipsilateral Biceps Femoris muscle.	after acute administration of apomorphine
Cerebral activity using H215O PET analysis of regional Cerebral Blood Flow (rCBF) on subjects while they received alternate randomized noxious (defined as pain threshold) and innocuous stimuli.	After administration of apomorphine

Collaborators and Investigators

• Sponsor: University Hospital, Toulouse
• Investigators: Principal Investigator: Christine BREFEL-COURBON, PhD, University Hospital, Toulouse

Study record dates

Study Major Dates

• Study Start: September 1, 2007
• Primary Completion (Actual): January 1, 2008
• Study Completion (Actual): March 1, 2008

Study Registration Dates

• First Submitted: September 4, 2007
• First Submitted That Met QC Criteria: September 4, 2007
• First Posted (Estimate): September 5, 2007

Study Record Updates

• Last Update Posted (Estimate): April 11, 2008
• Last Update Submitted That Met QC Criteria: April 10, 2008
• Last Verified: April 1, 2008

More Information

Terms related to this study

• Keywords: Pain; Parkinson's disease; Functional imaging; Nociceptive threshold; Cerebral activity; Dopamine agonist.
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Parkinsonian Disorders; Basal Ganglia Diseases; Movement Disorders; Synucleinopathies; Neurodegenerative Diseases; Parkinson Disease; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Autonomic Agents; Peripheral Nervous System Agents; Gastrointestinal Agents; Dopamine Agonists; Dopamine Agents; Emetics; Apomorphine
• Other Study ID Numbers: 0602308; PHRC 2006