Propiverine-induced Parkinsonism: a case report and a pharmacokinetic/pharmacodynamic study in mice

Haloperidol-induced catalepsy as an animal model for parkinsonism: A systematic review of experimental studies

Several useful animal models for parkinsonism have been developed so far. Haloperidol-induced catalepsy is often used as a rodent model for the study of motor impairments observed in Parkinson's disease and related disorders and for the screening of potential antiparkinsonian compounds. The objective of this systematic review is to identify publications that used the haloperidol-induced catalepsy model for parkinsonism and to explore the methodological characteristics and the main questions addressed in these studies. A careful systematic search of the literature was carried out by accessing articles in three different databases: Web of Science, PubMed and SCOPUS. The selection and inclusion of studies were performed based on the abstract and, subsequently, on full-text analysis. Data extraction included the objective of the study, study design and outcome of interest. Two hundred and fifty-five articles were included in the review. Publication years ranged from 1981 to 2020. Most studies used the model to explore the effects of potential treatments for parkinsonism. Although the methodological characteristics used are quite varied, most studies used Wistar rats as experimental subjects. The most frequent dose of haloperidol used was 1.0 mg/kg, and the horizontal bar test was the most used to assess catalepsy. The data presented here provide a framework for an evidence-based approach to the design of preclinical research on parkinsonism using the haloperidol-induced catalepsy model. This model has been used routinely and successfully and is likely to continue to play a critical role in the ongoing search for the next generation of therapeutic interventions for parkinsonism.

Drug-induced parkinsonism

INTRODUCTION

Drug-induced parkinsonism (DIP) is the second most common cause of parkinsonism after idiopathic Parkinson's disease (iPD). Initially reported as a complication of antipsychotics, it was later recognized as a common complication of antidepressants, calcium channel antagonists, gastrointestinal prokinetics, antiepileptic drugs and many other compounds. Despite being a major health problem in certain populations, it seems to be frequently overlooked by the medical community.

AREAS COVERED

This paper approaches the concept of DIP, reviews its epidemiology, clinical features and ancillary tests recommended for a correct diagnosis. The authors discuss the different drugs and its pathogenic mechanisms. The relevance of an early recognition and recommendations for a correct management are commented.

EXPERT OPINION

Prescribers need to remain vigilant for DIP, particularly in the elderly, patients taking multiple drugs and those with genetic risk factors involved in iPD. Cessation of the causing agent is the main treatment and there is no evidence of benefit for the use of anticholinergics or levodopa. If the medication cannot be withdrawn, it should be switched to agents with a lower risk of DIP.

Drug-induced parkinsonism

Drug-induced parkinsonism (DIP) is the second cause of akinetic rigid syndrome in the Western world and its prevalence is increasing and approaching that of idiopathic Parkinson's disease due to the ageing of the population and to the rising of polypharmacotherapy. DIP was initially reported as a complication of neuroleptics in psychiatric patients, but it has also been described with a great diversity of compounds such as antiemetics, drugs used for the treatment of vertigo, antidepressants, calcium channel antagonists, antiarrythmics, antiepileptics, cholinomimetics and other drugs. Although traditionally considered reversible, DIP may persist after drug withdrawal. At least 10% of patients with DIP develop persistent and progressive parkinsonism in spite of the discontinuation of the causative drug. Irreversible or progressive DIP has been considered as an indication of presymptomatic parkinsonian deficit, unmasked but not caused by the offending drug, but it could be explained by persistent toxicity of the responsible pharmacological agents on the nigrostriatal dopamine pathway. The best treatment of DIP is prevention, including the avoidance of prescription of causative drugs whenever it is not strictly necessary. In patients who require potentially risky medication, it is necessary to perform adequate monitoring for early parkinsonian deficits and early discontinuation if these deficits appear. Atypical neuroleptics are associated with lower risk than first generation antipsychotic drugs. Special precautions are needed in elderly subjects, in patients treated with multiple drugs for prolonged periods of time and in those with familial risk factors including familial parkinsonism or tremor, or in those with genetic variants of genes involved in idiopathic Parkinson's disease.

Central nervous system safety of anticholinergic drugs for the treatment of overactive bladder in the elderly

BACKGROUND

Overactive bladder (OAB) is characterized by urgency and increased frequency of micturition, with or without urinary urge incontinence. Anticholinergic agents are important in the treatment of OAB. However, concerns have emerged about their central nervous system (CNS) safety and the associated risk of cognitive impairment.

OBJECTIVE

This article describes the CNS adverse effects of anticholinergic drugs used for the treatment of OAB, with particular emphasis on their use in the elderly. Its objective is to help physicians make optimal choices when selecting anticholinergic treatment for OAB.

METHODS

: Relevant data from the literature were identified primarily through a MEDLINE search of articles published through December 2003. The search terms included overactive bladder, central nervous system, anticholinergic, and antimuscarinic. This was not intended to be a systematic review, and articles were chosen for inclusion based on their pertinence to the focus on treatment of OAB in the elderly.

RESULTS

Several anticholinergic drugs are available for the treatment of OAB, including oxybutymn, tolterodine, trospium chloride, and propiverine (not available in the United States). Among the agents reviewed, penetration of the blood-brain barrier (as predicted by lipophilicity, polarity, and molecular size and structure) is highest for oxybutymn, lower for tolterodine, and lowest for trospium chloride; limited data are available for propiverine. The total anticholinergic drug burden may also be important in determining the potential for CNS adverse effects. The spectrum of anticholinergic CNS adverse effects ranges from drowsiness to hallucinations, severe cognitive impairment, and even coma. The immediate-release (IR) and extended-release (ER) formulations of oxybutynin have been associated with cognitive impairment. In the only published clinical trial that was identified, no significant differences in CNS adverse effects were observed between the IR and ER formulations of tolterodine. There were few clinical data on the use of propiverine in patients with OAB. Trospium chloride has shown favorable CNS tolerability in postmarketing surveillance studies.

CONCLUSION

When considering treatment choices for patients with OAB, particularly the elderly, the potential CNS adverse effects of each anticholinergic agent must be weighed against the severity of OAB symptoms.

Drug-induced parkinsonism

BACKGROUND

Drug-induced parkinsonism is common but often unrecognized. In addition to neuroleptics, many medications of diverse chemical nature may induce or exacerbate parkinsonism

REVIEW SUMMARY

Reports in the literature of drug-induced parkinsonism or of an underlying parkinsonian disorder exacerbated by a medication were located using MEDLINE, and pertinent bibliographies were reviewed. The range of medications that may induce or exacerbate parkinsonism spans the medical specialties. Along with neuroleptics, selective-serotonin reuptake inhibitors, lithium, valproic acid, calcium channel blockers, antiarrhythmics, procholinergics, chemotherapeutics, amphotericin B, estrogens, and others have been implicated.

CONCLUSIONS

This review seeks to enhance clinicians' knowledge of potential medications producing iatrogenic parkinsonism and encourage their vigilance in recognizing it.

Effects of intrathecal injection of diatrizoate on dopamine receptors

RATIONALE AND OBJECTIVES

The authors performed this study to determine whether adverse reactions similar to those that occur in patients receiving antipsychotic medication may occur after inadvertent intrathecal injections of some contrast material.

MATERIALS AND METHODS

Recombinant human dopamine-2 (D-2) receptors were incubated together with tritiated (hydrogen 3) spiperone, a D-2 receptor agonist commonly used in binding studies, and three types of contrast material (sodium/meglumine diatrizoate; meglumine iothalamate; and iohexol) in different concentrations to determine competitive binding potentials. Nonspecific binding was also assessed. Membranes were washed, filtered, and counted in a scintillation counter.

RESULTS

At several different concentrations, diatrizoate demonstrated a potential to displace the binding of spiperone to the D-2 receptors, whereas the other two contrast materials tested (iothalamate meglumine and iohexol) showed only weak binding potentials.

CONCLUSION

Diatrizoate, which has been incriminated in most adverse reactions resulting from the inadvertent intrathecal injection of a contrast material, may produce symptoms similar to those of the neuroleptic malignant syndrome by blocking neurotransmission through dopamine receptors. Although antipsychotic drugs produce this parkinsonism-like effect only after prolonged use, it is probable that diatrizoate produces the effect immediately by virtue of the high concentrations that may accumulate at the base of the brain after myelography. Also worthy of note is the fact that the two other contrast materials that have produced a number of reported adverse reactions share a molecular similarity to diatrizoate that is not found with other contrast materials.

Muscarinic receptor binding characteristics in rat tissues after oral administration of oxybutynin and propiverine

Ex vivo muscarinic receptor binding of oxybutynin and propiverine, the most commonly used anticholinergic agents for the treatment in patients with urinary incontinence, was investigated in rat tissues. The oral administration of oxybutynin (50.8 and 127 micromol/kg) caused a significant increase in the apparent dissociation constant (Kd) for specific (-)-[3H]QNB binding in the rat bladder, prostate, submaxillary gland, heart and cerebral cortex, compared with each of the control values. Also, in the submaxillary gland of these rats, there was a reduction in the maximal number of binding sites (Bmax) for (-)-[3H]QNB binding. Similarly, oral administration of propiverine at doses of 74.3-297 micromol/kg brought about a significant increase in the Kd values for (-)-[3H]QNB binding in rat tissues including the bladder, and greater increase in Kd values was seen in the rat prostate, heart and submaxillary gland. On the other hand, oral administration of propiverine, unlike oxybutynin, resulted in very little reduction in the Bmax valules for (-)-[3H]QNB binding in the submaxillary gland. In conclusion, the present study has shown that oxybutynin and propiverine, after oral administration, bind significantly to muscarinic receptors in tissues such as the bladder, which is the target organ for the treatment of urinary incontinence, and that oxybutynin appears to exhibit long-term binding to muscarinic receptors in the salivary gland.

Quantitative prediction of catalepsy induced by amoxapine, cinnarizine and cyclophosphamide in mice

Parkinsonism can be a side effect of antipsychotic drugs, and has recently been reported with peripherally acting drugs such as calcium channel blockers, antiarrhythmic agents and so on. In this study, we examined the quantitative prediction of drug-induced catalepsy by amoxapine, cinnarizine and cyclophosphamide, which have been reported to induce parkinsonism. Dose-dependent catalepsy was induced by these drugs in mice. In vivo dopamine D(1), D(2) and muscarinic acetylcholine (mACh) receptor occupancies by these drugs in the striatum were also examined. The in vitro binding affinities (K(i) values) of amoxapine and cinnarizine to dopamine D(1), D(2) and mACh receptors in rat striatal synaptic membrane were 200 and 2900 nM, 58.4 and 76.4 nM and 379 and 290 nM, respectively. Cyclophosphamide did not bind to these receptors at concentrations up to 100 microM. Twenty drugs, including those mentioned above, showed a significant correlation between the observed intensity of catalepsy and the values predicted with a pharmacodynamic model (Haraguchi K, Ito K, Kotaki H, Sawada Y, Iga T. Prediction of drug-induced catalepsy based on dopamine D(1), D(2), and muscarinic acetylcholine receptor occupancies. Drug Metab Disp 1997; 25: 675-684) based on in vivo occupancy of dopamine D(1), D(2) and mACh receptors. We conclude that occupancy of dopamine D(1) and D(2) receptors contributes to catalepsy induction by amoxapine and cinnarizine.