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One hundred patients with Parkinson's disease (PD) aged 60 and above treated with levodopa were enrolled in this cross section study.The general conditions,medication,unified Parkinson's disease rating scale (UPDRS) scores and the incidence of levodopa-induced dyskinesia (LID) were documented.The incidence rate of LID in this group of PD patients was 37.0％ (37/100).The incidence was significantly higher in patients with levodopa treatment ≥ 4 years than that in patients with levodopa treatment ＜ 4 years (55％ vs.26％,x2 =8.770,P =0.003).The incidence rate ofpeak dosage dyskinesia in tremor-dominant PD patients was lower than that in rigidity-dominant PD patients(x2 =4.399,P =0.036).The incidence rate of LID was correlated with the duration of levodopa therapy.Amantadine may reduce the incidence of off dystonia.
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Objective To study the behavioural changes and biological effects of selective adenosine A2A receptor antagonist (CSC) in a rat model of levodopa(L-DOPA) -induced dyskinesia (LID).Methods The hemi-parkinsonian rat model was produced by stereotaxically injecting 6-OHDA to the right medial forebrain bundle. Rats were randomly divided into 4 treatment groups with a random number generating program to receive intraperitoneal injections twice daily for 21 days (n = 10): saline, L-DOPA at 25 mg/kg with benserazide at 6. 25 mg/kg, CSC at 2. 5 mg/kg alone and CSC at 2.5 mg/kg with L-DOPA at 25 mg/kg plus benserazide at 6. 25 mg/kg. Forepaw adjusting steps, abnormal involuntary movements (AIM) and rotational response duration were observed on 2, 9, 11,18 and 21 d. After sacrifice, the expression of adenosine A2A R and mGluR5 was observed by Western blot. Results Co-administration of LDOPA with CSC significantly increased the forelimb adjusting steps of parkinsonian rats during 21 days of treatment when compared to L-DOPA alone. CSC treatment alone increased the forelimb adjusting steps significantly. Co-administration of L-DOPA with CSC ( ( 11 ± 5 ) score) significantly decreased the AIM scores of limb and orolingual muscles when compared to L-DOPA alone (( 17 ± 4) score; t = 2. 44, P ＜0. 05). The subchronic L-DOPA treatment upregulated the striatal expression of adenosine A2A R and mGluR5. However, co-administration of L-DOPA with CSC reversed the shortening of the rotational motor response duration induced by L-DOPA administration during the period of the treatment and attenuated the LDOPA-induced upregulation of adenosine A2A R and mGluR5 expressions. Conclusions CSC improves motor function in a hemi-parkinson rat model, potentiates the antiparkinsonian effects with L-DOPA and partly attenuates LID. Co-administration of L-DOPA with CSC reverses the L-DOPA-induced upregulated expression of A2A R and mGluR5, indicating the involvement of both A2A R and mGluR5 in the onset and progression of LID. Adenosine A2AR antagonists may be promising drugs for treatment of LID.
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Introducción: Los síntomas extrapiramidales y en especial las disquinesias tardías, son la mayor limitante de la terapia con antipsicóticos, debido a la frecuencia de aparición durante el tratamiento y la falta de recursos para controlar estas reacciones adversas, por lo cual es necesario investigar nuevos recursos para el manejo de las disquinesias tardías. Objetivo: Evaluar el efecto de la ivermectina sobre las disquinesias tardías inducidas por haloperidol en ratas. Métodos: En un modelo de dosis única de haloperidol con ratas Sprague Dawley, se evalúo la capacidad de la ivermectina para evitar cambios en la conducta motora y la aparición de movimientos anormales. Adicionalmente, se implementó un modelo animal crónico conocido como VCM (vacuous chewing movements), donde se evaluó la frecuencia de movimientos orofaciales durante seis meses, al recibir simultaneamente haloperidol e ivermectina a dosis diferentes, comparandolo con un grupo control y otro grupo al que se le administró haloperidol. Resultados: La ivermectina no evitó los cambios inducidos por haloperidol en el comportamiento motor, ni la aparición de movimientos anormales en el modelo agudo. Tampoco modificó la frecuencia de movimientos orofaciales en el modelo de administración crónica de haloperidol. La ivermectina no indujo cambios en la conducta motora, ni la aparición de movimientos anormales en los modelos agudo y crónico. Conclusiones: Los hallazgos de este trabajo descartan a la ivermectina como candidata para el manejo de las disquinesias tardías y no permite aportar argumentos a la hipótesis GABAérgica en la fisiopatología de las disquinesias tardías. Adicionalmente, la ivermectina no induce movimientos anormales.
Introduction: Extrapiramidal symptoms and tardive dyskinesia are common problems associated with antypsychotic therapy. Basic and clinical research is warranted due to the lack of effective therapies aimed to the prevention and treatment of antipsychotic side effects. Objective: To evaluate the effect of ivermectin in rats with haloperidol induced tardive dyskinesia. Methods: The effect of ivermectin on motor behavior and abnormal movements was tested in Sprague-Dawley rats treated with a single dose of haloperidol. In addition, a chronic animal model known as VCM (vacuous chewing movements) was implemented with the objective to evaluate the effect of ivermectin on the frequency of orofacial movements during a period of six months. Results: Ivermectin does not prevent the motor behavior and frequency of abnormal movements induced by haloperidol in the acute model. Orofacial movements were not reduced with ivermectin in the chronic model. In addition, ivermectin was not associated with changes in motor behavior and abnormal movements in the acute and chronic model. Conclusions: Ivermectin is not a good candidate for the treatment of tardive dyskinesia and the results of this study do not support the GABAergic hypothesis in the physiopathology of tardive dyskinesia. Additionally, ivermectin does not induce abnormal movements.
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Rats , Antipsychotic Agents , Dyskinesia, Drug-Induced , Haloperidol , Ivermectin , RatsABSTRACT
Objective To study the effect of MK801 on behavioral changes and the possible mechanisms. Methods To observe the behavioral changes of levodopa induced dyskinesia (LID) rats during the period of chronic MK801 treatment, immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to measure the changes in expression of FosB, preproenkephalin (PPE) mRNA and prodynorphin (PDyn) mRNA in striatum, respectively. Double labling technique including immunohistochemistry of FosB and retrograde HRP transport tracing was used to observe the cell distribution of FosB. Results Pulsatile treatment with levodopa induced Abnormal involuntary movements (AIM) in PD rats, similar to LID in PD patients. FosB positive neurons and expressions of PPE mRNA and PDyn mRNA in striatum of 6-OHDA-lesioned hemisphere were increased in LID rats, and AIM scores of LID rats were reduced by MK801 treatment(41.9?15.6 vs 7.2?3.0), accompanied by the decrease in expressions of FosB and PDyn mRNA, but not PPE mRNA. Neurons immunoreactive for FosB were mainly located in striatonigral neurons which were labeled by cholera toxin-HRP (CT-HRP) injected in the substantia nigra pars reticulata (SNr). Conclusions MK801 could prevent the occurrence of dyskinesias induced by chronic levodopa treatment. The mechanism might be involved in the high expression of immediate early gene FosB and specific gene PDyn on the direct pathway. It suggests that LID might be related to the abnormal activity of direct pathway.
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0.05). A significant excess of C allele was in patients with TD compared to those without TD(? 2 =4.36,?=1,p0.05). Conclusion:Our result suggest that the T102C polymorphism in 5-HT2A receptor gene may be association with TD in chronic male schizophrenic patients