Abstract
The effects of centrally acting drugs on tremor were investigated in monkeys with ventromedial tegmental lesions exhibiting hypokinesia or hypokinesia and tremor. In monkeys with resting tremor, the administration of DL-5-HTP (5-hydroxytryptophan) or of DL-DOPA (3,4-dihydroxyphenylalanine) relieves the tremor, but the simultaneous administration of DL-5-HTP or DL-DOPA and atropine results in a much more pronounced relief. These results point to an imbalance between the cholinergic and adrenergic-serotonergic systems in parkinsonism.
In monkeys exhibiting hypokinesia, the administration of harmaline evokes a marked resting tremor of the extremities contralateral to the tegmental lesion. The production of tremor by harmaline is not abolished by lowering the striatal amine levels with specific inhibitors of amine synthesis. Administration of DL-5-HTP protects monkeys from tremors induced by harmaline, which might affect the functions of the central nervous system by interaction with receptors for serotonin. The present results further demonstrate the apparent role of biogenic amines in the extrapyramidal dysfunctions.
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Selected References
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- Goldstein M., Anagnoste B., Battista A. F., Owen W. S., Nakatani S. Studies of amines in the striatum in monkeys with nigral lesions. The disposition, biosynthesis and metabolites of [3H]dopamine and [14C]serotonin in the striatum. J Neurochem. 1969 Apr;16(4):645–653. doi: 10.1111/j.1471-4159.1969.tb06864.x. [DOI] [PubMed] [Google Scholar]
- Goldstein M., Anagnoste B., Owen W. S., Battista A. F. The effects of ventromedial tegmental lesions on the disposition of dopamine in the caudate nucleus of the monkey. Brain Res. 1967 Mar;4(2):298–300. doi: 10.1016/0006-8993(67)90013-3. [DOI] [PubMed] [Google Scholar]
- HORNYKIEWICZ O. [The tropical localization and content of noradrenalin and dopamine (3-hydroxytyramine) in the substantia nigra of normal persons and patients with Parkinson's disease]. Wien Klin Wochenschr. 1963 May 3;75:309–312. [PubMed] [Google Scholar]
- Koe B. K., Weissman A. p-Chlorophenylalanine: a specific depletor of brain serotonin. J Pharmacol Exp Ther. 1966 Dec;154(3):499–516. [PubMed] [Google Scholar]
- POIRIER L. J., SOURKES T. L. INFLUENCE OF THE SUBSTANTIA NIGRA ON THE CATECHOLAMINE CONTENT OF THE STRIATUM. Brain. 1965 Mar;88:181–192. doi: 10.1093/brain/88.1.181. [DOI] [PubMed] [Google Scholar]