The application of L·DOPA (L-3, 4-dihydroxyphenylalanine) to the treatment of extrapyramidal disorders has been extremely beneficial for parkinsonism 1)-8). At the same time several side-effects have been recognized. Among them, the appearance of dyskinesia poses an important problem 8)-13l , but causative mechanisms of L·DOPA induced dyskinesia are not yet sufficiently elucidated. Such dyskine...

Background: DARPP-32 is implicated in L-DOPA-induced dyskinesia. Results: PKA-dependent phosphorylation of DARPP-32 in a distinct subset of striatal neurons is required for L-DOPA-induced activation of ERK and mTORC1. Conclusion: PKA-dependent phosphorylation of DARPP-32 plays a critical role in dyskinesia and associated signaling alterations. Significance: The PKA/DARPP-32 cascade is a key tar...

A direct association between aging and drug-induced dyskinesia has been reported by several investigators. Iminiodipropionitrile (IDPN), a prototype nitrile compound produces a motor syndrome in rodents, which resembles neuroleptic drug induced dyskinesia. In this investigation attempt has been made to study the effect of age on IDPN induced vestibular hair cell degeneration and resulting dyski...

Title: Drug-induced dyskinesia in Parkinson's disease. Should success in clinical management be a function of improvement of motor repertoire rather than amplitude of dyskinesia?

The present study investigated whether the rotation rate induced by amphetamine in 6-OHDA-lesioned rats was predictive of development of L-DOPA-induced dyskinesia (LID) and success of the lesion procedure in our experimental settings. We collected data from 312 6-OHDA-lesioned rats (from different sets of experiments). Rats were subjected to the amphetamine-induced rotation test (2.5mg/kg) and ...

It has been suggested, based on rodent studies, that levodopa (L-dopa) induced dyskinesia is associated with a disrupted blood-brain barrier (BBB). We have investigated BBB integrity with in vivo neuroimaging techniques in six 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) lesioned primates exhibiting L-dopa-induced dyskinesia. Magnetic resonance imaging (MRI) performed before and after in...

Electromyographic (EMG) activity of abnormal involuntary movements and their modifications after Piribedil, a dopaminergic agonist, were analysed in patients presenting with tremor or tardive dyskinesia induced by treatment with neuroleptics. Quantitative analysis of EMG bursts and of their phase relationships with bursts of antagonist muscles revealed differences between tremor and tardive dys...