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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00524914
Recruitment Status : Completed
First Posted : September 5, 2007
Last Update Posted : April 11, 2008
Information provided by:
University Hospital, Toulouse

Brief Summary:
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.

Condition or disease Intervention/treatment Phase
Parkinson's Disease Drug: apomorphine Drug: placebo Not Applicable

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.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 16 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Basic Science
Official Title: Apomorphine Effect on Nociceptive Perception in Parkinson's: a Clinical and Imaging Study.
Study Start Date : September 2007
Actual Primary Completion Date : January 2008
Actual Study Completion Date : March 2008

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: 1
Drug: apomorphine
Acute apomorphine subcutaneous 3 mg

Placebo Comparator: 2
Drug: placebo
placebo subcutaneous

Primary Outcome Measures :
  1. 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. [ Time Frame: the primary outcome is measured after acute administration of apomorphine ( after 30 minutes ) ]

Secondary Outcome Measures :
  1. 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. [ Time Frame: after acute administration of apomorphine ]
  2. 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. [ Time Frame: After administration of apomorphine ]

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Ages Eligible for Study:   30 Years to 70 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00524914

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Service de Neurologie
Toulouse, France, 31059
Sponsors and Collaborators
University Hospital, Toulouse
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Principal Investigator: Christine BREFEL-COURBON, PhD University Hospital, Toulouse
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Responsible Party: LLAU Marie-Elise, University Hospital Toulouse Identifier: NCT00524914    
Other Study ID Numbers: 0602308
PHRC 2006
First Posted: September 5, 2007    Key Record Dates
Last Update Posted: April 11, 2008
Last Verified: April 2008
Keywords provided by University Hospital, Toulouse:
Parkinson's disease
Nociceptive threshold
Functional imaging
Cerebral activity
Dopamine agonist.
Additional relevant MeSH terms:
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Parkinson Disease
Parkinsonian Disorders
Basal Ganglia Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Movement Disorders
Neurodegenerative Diseases
Physiological Effects of Drugs
Autonomic Agents
Peripheral Nervous System Agents
Gastrointestinal Agents
Dopamine Agonists
Dopamine Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action