Effect of ethanol on the central oscillator in essential tremor.
We investigated the effects of ethanol and diazepam on the central, mechanical, and mechanical reflex components of tremor in patients with essential tremor (ET). A double-blind crossover study (ethanol or diazepam) was conducted on 2 separate days. Dose of ethanol or diazepam was calculated in each individual according to height, weight, and age in 10 patients with ET. The postural tremor amplitude at the wrist was recorded using a three-dimensional accelerometer placed on the dorsum of the hand. Electromyogram (EMG) was recorded with surface electrodes placed on the forearm extensors and flexors. To separate central and mechanical (reflex) components, a 500-g weight was placed on the dorsum of the hand during a second tremor measurement. Tremor recordings were done at baseline and 30, 60, 90, and 120 minutes after drug ingestion. Ethanol and diazepam blood levels were measured at baseline and after 20, 40, 80, and 120 minutes. Blood ethanol and diazepam levels were highest after 40 and 80 minutes. The amplitude of the central component 60 minutes after ingestion of ethanol was decreased significantly (P = 0.029) compared with diazepam. Our findings suggest that the improvement in tremor after ethanol ingestion was due, at least in part, to an effect on a central oscillator.
Zeuner
Kirsten E
KE
Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-1428, USA.
Molloy
Fiona M
FM
Shoge
Richard O
RO
Goldstein
Susanne R
SR
Wesley
Robert
R
Hallett
Mark
M
D001683:Biological Clocks / Q000187:drug effects*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004576:Electromyography; D020329:Essential Tremor / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D000431:Ethanol / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology; D011795:Surveys and Questionnaires
D000697:Central Nervous System Stimulants; D000431:Ethanol