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Ole Isacson: Development of New Therapies for Parkinson's Disease
23:53

Ole Isacson: Development of New Therapies for Parkinson's Disease

Published on: April 29, 2007

Modification of the actions of some neuroactive drugs by growth hormone

L C Tang, G C Cotzias

    Archives of Neurology
    |February 1, 1976
    PubMed

    Insights

    Growth hormone (GH) increases during levodopa treatment for Parkinson's disease. Animal studies suggest GH may influence levodopa's effectiveness and brain chemistry, potentially impacting Parkinson's symptoms.

    Area of Science:

    • Neuroscience
    • Endocrinology
    • Pharmacology

    Background:

    • Parkinson's disease patients exhibit altered serum growth hormone (GH) levels.
    • Levodopa treatment for Parkinson's disease induces diurnal rises in GH.
    • Chronic GH elevation may contribute to the "on-off" phenomenon in Parkinson's patients.

    Purpose of the Study:

    • To investigate the effects of growth hormone (GH) on brain chemistry and levodopa response in a mouse model.
    • To explore the potential role of GH in modulating dopaminergic pathways relevant to Parkinson's disease.

    Main Methods:

    • Mice were pretreated with growth hormone (GH).
    • Cerebral concentrations of dopa and dopamine were measured in levodopa-treated mice.
    • Accumulation of tritiated apomorphine and thymidine in the brain was assessed.
    • Behavioral responses to various dopaminergic agents were evaluated.

    Main Results:

    • GH pretreatment increased cerebral dopa and dopamine levels in levodopa-treated mice.
    • GH enhanced the brain accumulation of injected tritiated apomorphine and thymidine.
    • GH administration potentiated behavioral responses to levodopa and other related compounds.

    Conclusions:

    • Growth hormone influences central dopaminergic activity and neurotransmitter metabolism.
    • GH may modulate the efficacy of levodopa therapy in Parkinson's disease.
    • These findings support further investigation into GH's role in Parkinson's disease pathophysiology and treatment.

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