Striatal dopaminergic function in restless legs syndrome

Objective: To use PET to study striatal dopaminergic function in restless legs syndrome (RLS). Background: RLS is a common disorder experienced by as much as 5% of the population. It has been suggested that this condition is associated with a disturbance of dopaminergic transmission. Methods: The authors measured nigrostriatal terminal dopamine storage with 18F-dopa and striatal D2 receptor binding with 11C-raclopride PET in 13 RLS patients, five of whom were receiving treatment with l-dopa at the time of scanning. RLS results were compared with those of age-matched control subjects. Results: Mean caudate and putamen 18F-dopa uptake were mildly reduced in the RLS patients compared with control subjects, and this reached significance (p = 0.04) in the putamen. Mean D2 binding was reduced in the caudate (p = 0.01) and the putamen (p = 0.008) in RLS patients compared with control subjects. Six of the 13 RLS patients had caudate and putamen D2 binding reduced below the control range. Three other RLS patients showed only reduced putamen D2 binding. There were no significant differences in striatal 18F-dopa uptake or D2 binding between l-dopa–naive and l-dopa–treated RLS patients. Conclusions: These PET findings support the hypothesis of central dopaminergic dysfunction in RLS.

[1]  C D Marsden,et al.  Differing patterns of striatal 18F‐dopa uptake in Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy , 1990, Annals of neurology.

[2]  C Trenkwalder,et al.  Cerebral generators involved in the pathogenesis of the restless legs syndrome , 1997, Annals of neurology.

[3]  R. Myers,et al.  Quantitation of Carbon‐11‐labeled raclopride in rat striatum using positron emission tomography , 1992, Synapse.

[4]  W. Gibb,et al.  The restless legs syndrome. , 1986, Postgraduate medical journal.

[5]  S. Chokroverty,et al.  Review and videotape recognition of idiopathic restless legs syndrome , 1991, Movement disorders : official journal of the Movement Disorder Society.

[6]  A. Malhotra,et al.  Schizophrenia is associated with elevated amphetamine-induced synaptic dopamine concentrations: evidence from a novel positron emission tomography method. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[7]  A. Lammertsma,et al.  Simplified Reference Tissue Model for PET Receptor Studies , 1996, NeuroImage.

[8]  D. Brooks,et al.  Striatal D1 and D2 receptor binding in patients with Huntington's disease and other choreas. A PET study. , 1995, Brain : a journal of neurology.

[9]  D J Brooks,et al.  Comparison of Methods for Analysis of Clinical [11C]Raclopride Studies , 1996, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[10]  S. O’Keeffe,et al.  Iron status and restless legs syndrome in the elderly. , 1994, Age and ageing.

[11]  C. Prasad,et al.  REM sleep deprivation alters dopamine D2 receptor binding in the rat frontal cortex , 1995, Pharmacology Biochemistry and Behavior.

[12]  J. Jankovic,et al.  Restless legs syndrome , 1996, Neurology.

[13]  G. Sedvall,et al.  Quantitative analysis of D2 dopamine receptor binding in the living human brain by PET. , 1986, Science.

[14]  Y. Agid,et al.  Levodopa‐induced dyskinesias in Parkinson's disease phenomenology and pathophysiology , 1994, Movement disorders : official journal of the Movement Disorder Society.

[15]  D. J. Brooks,et al.  In vivo studies on striatal dopamine D1 and D2 site binding in L-dopa-treated Parkinson's disease patients with and without dyskinesias , 1997, Neurology.

[16]  R. Godbout,et al.  Treatment of restless legs syndrome and periodic movements during sleep with , 1988, Neurology.

[17]  G. Lavigne,et al.  Restless legs syndrome and sleep bruxism: prevalence and association among Canadians. , 1994, Sleep.

[18]  Christopher Earley,et al.  Toward a better definition of the restless legs syndrome , 1995, Movement disorders : official journal of the Movement Disorder Society.

[19]  C. Trenkwalder,et al.  Reflex studies and MRI in the restless legs syndrome , 1996, Acta neurologica Scandinavica.

[20]  C D Marsden,et al.  The relationship between locomotor disability, autonomic dysfunction, and the integrity of the striatal dopaminergic system in patients with multiple system atrophy, pure autonomic failure, and Parkinson's disease, studied with PET. , 1990, Brain : a journal of neurology.

[21]  M. Gilardi,et al.  Physical performance of the latest generation of commercial positron scanner , 1988 .

[22]  R. Godbout,et al.  Familial restless legs with periodic movements in sleep , 1985, Neurology.

[23]  R. Roth,et al.  Pharmacology of mesocortical dopamine neurons. , 1983, Pharmacological reviews.