Pharmacodynamics of levodopa in Parkinson's disease

Clinical and Experimental Pharmacology & Physiology
J G Nutt

Abstract

1. Levodopa markedly reduces parkinsonism during the first years of treatment. However, with continued therapy the response to levodopa becomes erratic and is complicated by involuntary movements. To improve the therapy of parkinsonism, the challenge is to understand why fluctuations in response develop and, once developed, what controls the moment to moment motor status. 2. In patients with a fluctuating response to levodopa, three distinct responses can be recognized: a short-duration response, a long-duration response and a negative response. 3. The short-duration response, measured in minutes to hours, has a steep concentration-response relationship such that the response appears 'all or nothing.' The duration of effect is dose-responsive. The short-duration response becomes shorter during chronic therapy, possibly because of tolerance. The onset to effect becomes briefer and the magnitude of the response becomes larger during chronic therapy, possibly because of sensitization. 4. The long-duration response, measured in days to weeks, develops and decays slowly. The rate of decay is proportional to the severity of the parkinsonism and therefore this response may relate to dopamine storage capacity of remaining nerve termina...Continue Reading

References

Jan 1, 1992·Movement Disorders : Official Journal of the Movement Disorder Society·M ContinA Baruzzi
Jan 2, 1989·European Journal of Pharmacology·G S RobertsonH A Robertson
Jul 1, 1989·Neurology·T SiddiqueM Speer
Apr 13, 1988·European Journal of Pharmacology·M RubinsteinF J Stefano
Jan 1, 1986·Clinical Neuropharmacology·J A Kaye, R G Feldman
Feb 13, 1969·The New England Journal of Medicine·G C CotziasR Gellene
Feb 16, 1967·The New England Journal of Medicine·G C CotziasL M Schiffer
Jul 1, 1994·Neurology·H SugieM Ito
Apr 1, 1994·Journal of Neurology, Neurosurgery, and Psychiatry·A J HughesA J Lees
Apr 1, 1994·Journal of Neurology, Neurosurgery, and Psychiatry·G HarwoodC D Marsden

❮ Previous
Next ❯

Citations

Aug 21, 2008·Nature Reviews. Neuroscience·Peter Jenner
Nov 19, 2004·Journal of Neurology, Neurosurgery, and Psychiatry·R KatzenschlagerA J Lees
Jun 11, 2004·Clinical Neuropharmacology·Alessandra MongeGianpietro Nordera
Jul 5, 2017·Expert Review of Medical Devices·Parisa Farzanehfar, Malcolm Horne
Aug 2, 2001·Movement Disorders : Official Journal of the Movement Disorder Society·E NurmiJ O Rinne
Jun 1, 2011·Movement Disorders : Official Journal of the Movement Disorder Society·C Warren OlanowKarl Kieburtz
Jul 21, 2017·Frontiers in Neurology·Gregory L Willis, Christopher B Freelance
Sep 27, 2018·Frontiers in Computational Neuroscience·Ritesh A RamdhaniBrian H Kopell

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.