Dopamine depletion in wistar rats with epilepsy.

The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model's chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo's model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.

Muscarinic Cholinergic Receptor Agonist and Peripheral Antagonist for Schizophrenia.

BACKGROUND: The muscarinic receptor agonist xanomeline has antipsychotic properties and is devoid of dopamine receptor-blocking activity but causes cholinergic adverse events. Trospium is a peripherally restricted muscarinic receptor antagonist that reduces peripheral cholinergic effects of xanomeline. The efficacy and safety of combined xanomeline and trospium in patients with schizophrenia are unknown. METHODS: In this double-blind, phase 2 trial, we randomly assigned patients with schizophrenia in a 1:1 ratio to receive twice-daily xanomeline-trospium (increased to a maximum of 125 mg of xanomeline and 30 mg of trospium per dose) or placebo for 5 weeks. The primary end point was the change from baseline to week 5 in the total score on the Positive and Negative Syndrome Scale (PANSS; range, 30 to 210, with higher scores indicating more severe symptoms of schizophrenia). Secondary end points were the change in the PANSS positive symptom subscore, the score on the Clinical Global Impression-Severity (CGI-S) scale (range, 1 to 7, with higher scores indicating greater severity of illness), the change in the PANSS negative symptom subscore, the change in the PANSS Marder negative symptom subscore, and the percentage of patients with a response according to a CGI-S score of 1 or 2. RESULTS: A total of 182 patients were enrolled, with 90 assigned to receive xanomeline-trospium and 92 to receive placebo. The PANSS total score at baseline was 97.7 in the xanomeline-trospium group and 96.6 in the placebo group. The change from baseline to week 5 was -17.4 points with xanomeline-trospium and -5.9 points with placebo (least-squares mean difference, -11.6 points; 95% confidence interval, -16.1 to -7.1; P<0.001). The results for the secondary end points were significantly better in the xanomeline-trospium group than in the placebo group, with the exception of the percentage of patients with a CGI-S response. The most common adverse events in the xanomeline-trospium group were constipation, nausea, dry mouth, dyspepsia, and vomiting. The incidences of somnolence, weight gain, restlessness, and extrapyramidal symptoms were similar in the two groups. CONCLUSIONS: In a 5-week trial, xanomeline-trospium resulted in a greater decrease in the PANSS total score than placebo but was associated with cholinergic and anticholinergic adverse events. Larger and longer trials are required to determine the efficacy and safety of xanomeline-trospium in patients with schizophrenia. (Funded by Karuna Therapeutics and the Wellcome Trust; ClinicalTrials.gov number, NCT03697252.).

Assessment of Memory Function in Pilocarpine-induced Epileptic Mice.

Cognitive impairment is one of the most common comorbidities in temporal lobe epilepsy. To recapitulate epilepsy-associated cognitive decline in an animal model of epilepsy, we generated pilocarpine-treated chronic epileptic mice. We present a protocol for three different behavioral tests using these epileptic mice: novel object location (NL), novel object recognition (NO), and pattern separation (PS) tests to evaluate learning and memory for places, objects, and contexts, respectively. We explain how to set the behavioral apparatus and provide experimental procedures for the NL, NO, and PS tests following an open field test that measures the animals' basal locomotor activities. We also describe the technical advantages of the NL, NO, and PS tests with respect to other behavioral tests for assessing memory function in epileptic mice. Finally, we discuss possible causes and solutions for epileptic mice failing to make 30 s of good contact with the objects during the familiarization sessions, which is a critical step for successful memory tests. Thus, this protocol provides detailed information about how to assess epilepsy-associated memory impairments using mice. The NL, NO, and PS tests are simple, efficient assays that are appropriate for the evaluation of different kinds of memory in epileptic mice.

Gulf War Illnesses are autoimmune conditions caused by the direct effect of the nerve gas prophylaxis drug (pyridostigmine bromide) on anergic immune system lymphocytes.

Immune system dysregulation in 1991 Gulf War Veterans was caused in part by the nerve gas prophylactic drug pyridostigmine bromide (PB) by direct agonist activation of muscarinic receptors on anergic B and T lymphocytes, leading to multiple types of autoimmune illnesses, and this effect may have been potentiated by combat stress.

A suspected case of drug-induced tubulointerstitial nephritis by pilocarpine hydrochloride.

A 63-year-old man with pharyngeal cancer had been prescribed pilocarpine hydrochloride for xerostomia after concomitant chemoradiotherapy. After 6 months of taking pilocarpine hydrochloride, he was referred to our hospital due to gradually developing renal insufficiency. The patient underwent detailed urinalysis, blood chemistry analysis, immune-serology testing. A renal biopsy was also performed. He was diagnosed with chronic tubulointerstitial nephritis (TIN) caused by lymphocytic infiltration of the interstitium, tubular atrophy, and interstitial fibrotic changes. Infections, autoimmune diseases, and genetic factors were ruled out as causes of TIN; a drug-induced lymphocyte stimulation test confirmed that he had high stimulation index scores for pilocarpine hydrochloride and a normal range stimulation score for other supplements. These results indicated that the TIN could have been induced by pilocarpine hydrochloride. Drug discontinuation partly improved his renal function and tubule marker levels. To our knowledge, this is the first report of TIN following administration of pilocarpine hydrochloride. This finding could contribute to future treatment decisions for patients with TIN and those using pilocarpine hydrochloride.

Risk of Parkinson disease in Sjögren syndrome administered ineffective immunosuppressant therapies: A nationwide population-based study.

To determine the incidence and risk of Parkinson disease (PD) in patients with Sjögren syndrome (SS) according to a nationwide population-based database.In total, 12,640 patients in the SS cohort and 50,560 in the non-SS cohort were enrolled from Taiwan's National Health Insurance Research Database from 2000 to 2010. We used the Cox multivariable proportional hazards model to determine the risk factors for PD in the SS cohort.We observed an increased incidence of PD in patients with SS, with a crude hazard ratio (HR) of 1.40 and an adjusted HR (aHR) of 1.23. The cumulative incidence of PD was 1.95% higher in the SS cohort than in the non-SS cohort. The SS cohort had an elevated HR under medication use, namely cevimeline and pilocarpine (crude HR, 1.28), hydroxychloroquine (crude HR, 1.43; aHR, 1.46), and methylprednisolone (crude HR, 2.21; aHR, 1.49). Patients receiving other non-hydroxychloroquine immunosuppressant therapies had a lower risk (aHR, 0.86) of PD. Furthermore, patients with SS aged 20 to 49 years had a 1.93-fold higher risk of PD than did those without SS (aHR, 1.93). The risk of PD was higher (aHR, 2.20) in patients with SS without comorbidities than in those with comorbidities. The aHR of PD significantly increased when the follow-up period exceeded 9 years (aHR, 1.93).We determined an increased risk of PD in patients with SS. Further investigation is warranted to determine the possible underlying mechanisms and the potential role of non-hydroxychloroquine immunosuppressants in ameliorating PD.

Efficacy and Safety of Tolterodine and Pilocarpine in Patients with Overactive Bladder.

PURPOSE: We evaluated the efficacy and safety of a combination of 2 mg tolterodine and 9 mg pilocarpine, vs tolterodine monotherapy in patients with overactive bladder. MATERIALS AND METHODS: We enrolled patients with overactive bladder symptoms in a multicenter, randomized, double-blind, parallel, active control study. Patients were randomized to the combination or 2 mg tolterodine twice daily for 12 weeks. After the double-blind period finished all patients were started on the combination for 12 weeks. Study co-primary end points were the change from baseline in the mean number of daily micturitions and cumulative incidence of dry mouth at the end of 12 weeks. Secondary end points were other overactive bladder symptoms, the total xerostomia inventory score and results of a visual analogue scale for dry mouth at the end of 12 and 24 weeks. RESULTS: The mean change in the number of daily micturitions from baseline to 12 weeks was -1.49 and -1.74 in the combination and tolterodine monotherapy groups, respectively. The mean difference was -0.26 (95% CI -0.79-0.27), confirming noninferiority. At 12 weeks the incidence of dry mouth was lower in the combination group than in the tolterodine monotherapy group (30.0% vs 42.9%, p = 0.009). All secondary and other efficacy outcomes related to overactive bladder symptoms improved in each group with no significant differences between the groups at 12 weeks. Changes from baseline in the total xerostomia inventory score and the visual analogue scale for dry mouth were significantly lower in the combination group than in the tolterodine monotherapy group. CONCLUSIONS: Tolterodine and pilocarpine alleviated dry mouth in patients with overactive bladder while maintaining anticholinergic efficacy similar to that of tolterodine.

Pharmacokinetics and Tissue Distribution of Pilocarpine After Application to Eyelid Skin of Rats.

Extending the delivery of drugs into the eyes while reducing systemic bioavailability is of utmost importance in the management of chronic ocular diseases. Topical application onto the lower eyelid skin, as an alternative to eye drops, is seen to be a valuable strategy in the treatment of chronic eye diseases. To elucidate the critical value of delivering drugs in solution onto the eyeball through the eyelid skin, pharmacokinetic studies of pilocarpine were conducted, and the results were verified using a direct pharmacodynamic study in rats. The mean residence time of pilocarpine after topical eyelid application to the eyelid skin, conjunctiva, eyeball, and plasma were 14.9, 8.50, 6.29, and 8.11 h, respectively. Conjunctiva and eyeball concentrations of pilocarpine at 8 h were 80-fold and 8-fold higher after topical eyelid application, respectively, than those for eye drops. Pupillary constriction was sustained over 8 h after topical eyelid application. Topical eyelid skin application exhibited a localized drug absorption and specific drug accumulation in the ocular tissues. Hence, it is rational to prepare topical formulations directed onto the eyelid skin, which is suitable for drugs required for long-term treatment.

Salt, sweat, and unclear? Diaphoresis and hypernatremia in end-stage kidney disease: Questions.

This quiz will discuss two patients with end-stage kidney disease (ESKD) on dialysis presenting with diaphoresis and hypernatremia.

Engineered Context-Sensitive Agonism: Tissue-Selective Drug Signaling through a G Protein-Coupled Receptor.

Drug discovery strives for selective ligands to achieve targeted modulation of tissue function. Here we introduce engineered context-sensitive agonism as a postreceptor mechanism for tissue-selective drug action through a G protein-coupled receptor. Acetylcholine M2-receptor activation is known to mediate, among other actions, potentially dangerous slowing of the heart rate. This unwanted side effect is one of the main reasons that limit clinical application of muscarinic agonists. Herein we show that dualsteric (orthosteric/allosteric) agonists induce less cardiac depression ex vivo and in vivo than conventional full agonists. Exploration of the underlying mechanism in living cells employing cellular dynamic mass redistribution identified context-sensitive agonism of these dualsteric agonists. They translate elevation of intracellular cAMP into a switch from full to partial agonism. Designed context-sensitive agonism opens an avenue toward postreceptor pharmacologic selectivity, which even works in target tissues operated by the same subtype of pharmacologic receptor.

Allergic Contact Dermatitis to Ophthalmic Medications: Relevant Allergens and Alternative Testing Methods.

Allergic contact dermatitis is an important cause of periorbital dermatitis. Topical ophthalmic agents are relevant sensitizers. Contact dermatitis to ophthalmic medications can be challenging to diagnose and manage given the numerous possible offending agents, including both active and inactive ingredients. Furthermore, a substantial body of literature reports false-negative patch test results to ophthalmic agents. Subsequently, numerous alternative testing methods have been described. This review outlines the periorbital manifestations, causative agents, and alternative testing methods of allergic contact dermatitis to ophthalmic medications.

Efficacy and safety of pilocarpine for radiation-induced xerostomia in patients with head and neck cancer: A systematic review and meta-analysis.

BACKGROUND: Pilocarpine has been used widely in the treatment of dry mouth and glaucoma. In this review, the authors assessed the efficacy and safety of pilocarpine for patients with head and neck cancer who have radiation-induced xerostomia. TYPES OF STUDIES REVIEWED: The authors conducted a systematic search including meta-analyses and randomized controlled trials in the following databases: MEDLINE, Embase, Cochrane Library, and Science Citation Index Expanded. The primary outcome was the severity of xerostomia (measured using visual analog scale [VAS] scores). Adverse events were other outcomes of interest. The authors performed meta-analyses where appropriate. The authors used the Cochrane Collaboration's tool for assessing risk of bias to assess the quality of the study. RESULTS: The authors identified 6 studies (including 752 patients in total). The results of a meta-analysis of 3 articles showed that pilocarpine was associated with a 12-point increase in VAS score (mean difference, 12.00; 95% confidence interval [CI], 1.93-22.08; P = .02) and higher rates of adverse events compared with placebo in terms of sweating (odds ratio [OR], 3.71; 95% CI, 2.34-5.86; P < .00001). There were no differences in rhinitis (OR, 1.21; 95% CI, 0.68-2.16; P = .52) and nausea (OR, 1.44; 95% CI, 0.83-2.49; P = .19). CONCLUSIONS AND PRACTICAL IMPLICATIONS: On the basis of the best available evidence, the results of this meta-analysis provide evidence that pilocarpine offers statistically significant clinical benefits for the symptomatic treatment of radiation-induced xerostomia in patients with head and neck cancer. However, the authors of this systematic review found the best available evidence in the meta-analysis in 3 studies, 1 of which showed no effect. The authors of this systematic review suggest that these patients take 5 milligrams of pilocarpine 3 times daily, and that there is need for further study.

Underactive Bladder in Older Adults.

Overactive bladder is one of the most common bladder problems, but an estimated 20 million Americans have underactive bladder (UAB), which makes going to the bathroom difficult, increases the risk of urinary tract infections, and even leads to institutionalization. This article provides an overview of UAB in older adults, and discusses the prevalence, predisposing factors, cause, clinical investigations, and treatments. At present, there is no effective therapy for UAB. A great deal of work still needs to be done on understanding the pathogenesis and the development of effective therapies.

Parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy.

BACKGROUND: This is an updated version of the original Cochrane review on parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy (published in Issue 3, 2007). Salivary gland dysfunction is a predictable side effect of radiotherapy to the head and neck region. Pilocarpine hydrochloride (a choline ester) is licensed in many countries for the treatment of radiation-induced salivary gland dysfunction. Other parasympathomimetics have also been used 'off licence' in the treatment of this condition. OBJECTIVES: To determine the efficacy and tolerability of parasympathomimetic drugs in the treatment of radiation-induced salivary gland dysfunction (specifically radiation-induced xerostomia). SEARCH METHODS: For this update, we ran searches of the Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 6), MEDLINE, EMBASE, and CINAHL in July 2015. We checked the reference lists of retrieved articles for additional studies, contacted experts in the field for unpublished and ongoing trials, and contacted relevant pharmaceutical companies for unpublished and ongoing trials. SELECTION CRITERIA: The selection criteria for the review were: 1) randomised controlled trials; 2) people suffering from radiation-induced salivary gland dysfunction; 3) people treated with parasympathomimetic drugs; and 4) assessable data available on primary outcome measure. DATA COLLECTION AND ANALYSIS: The two review authors independently collected data from the full-text version of relevant papers including: 1) citation details; 2) participants; 3) interventions; 4) assessments; 5) outcomes (that is efficacy, tolerability); and 6) quality issues.Due to a lack of appropriate data, we were unable to perform a meta-analysis. MAIN RESULTS: In the original review, three studies, including a total of 298 participants, fulfilled the inclusion criteria. All three studies involved the use of pilocarpine hydrochloride. We have included no additional studies in the update of the review; we have excluded eight additional studies.The data suggest that pilocarpine hydrochloride is more effective than placebo and at least as effective as artificial saliva. The response rate was 42% to 51%. The time to response was up to 12 weeks. The overall side effect rate was high, and side effects were the main reason for withdrawal (6% to 15% of participants taking 5 mg three times a day had to withdraw). The side effects were usually the result of generalised parasympathomimetic stimulation (for example sweating, headaches, urinary frequency, vasodilatation). Response rates were not dose dependent, but side effect rates were dose dependent. AUTHORS' CONCLUSIONS: There is limited evidence to support the use of pilocarpine hydrochloride in the treatment of radiation-induced xerostomia. Currently, there is little evidence to support the use of other parasympathomimetic drugs in the treatment of radiation-induced xerostomia. Available studies suggest that approximately half of patients will respond, but side effects can be problematic. The conclusions of the update are the same as the conclusions of the original review, since no new relevant studies have been published in the interim.

Association between Glaucoma Medication Usage and Dry Eye in Taiwan.

PURPOSE: To evaluate the relationship between glaucoma medication usage and dry eye using a Taiwan nationally representative sample. METHODS: We identified patients with glaucoma diagnoses (ICD-9-CM [International Classification of Diseases, Ninth Revision, Clinical Modification] codes 365) from Taiwan claims data. The study group included 2065 glaucoma patients with newly diagnosed dry eye (ICD-9-CM code 375.15) identified during 2000 and 2011. The control subjects were 8260 glaucoma patients without dry eye who were frequency matched for age, sex, and the year of the index date. The following variables were considered: sex (male/female) and age (12 to 34 years, 35 to 49 years, 50 to 64 years, and ≥ 65 years). Six available glaucoma drugs in Taiwan were analyzed, namely, prostaglandin analog, ß-blocker, carbonic anhydrase inhibitor, α-agonists, pilocarpine, and combination drugs. Univariate and multivariate unconditional logistic regressions were used to estimate the effects of glaucoma treatment and comorbidities on the risk of dry eye as indicated by odds ratios (ORs) with 95% confidence intervals (CIs). Further analysis was performed to assess the dose-response effect on the risk of dry eye according to the cumulative number of different types of glaucoma medications used. RESULTS: Among the 2065 dry eye case patients, 63.3% were female and 48.9% were aged 65 years and older. After adjusting for potential confounding factors, an increased risk of dry eye was observed for all glaucoma medications (prostaglandin analog: adjusted OR, 1.48; 95% CI, 1.30 to 1.69; ß-blocker: adjusted OR, 1.57; 95% CI, 1.35 to 1.83; carbonic anhydrase inhibitor: adjusted OR, 1.38; 95% CI, 1.20 to 1.59; pilocarpine: adjusted OR, 1.19; 95% CI, 1.07 to 1.32; combination drugs: adjusted OR, 1.32; 95% CI, 1.09 to 1.58) with the exception of α-agonists. The adjusted OR of having dry eye increased with the number of glaucoma medications used. Similar trends were observed for both female and male subjects. CONCLUSIONS: An increased number of glaucoma medications used may increase dry eye risk, particularly in subjects who use more than two types of glaucoma medications and in female subjects. Clinicians should be cautious when prescribing medications for glaucoma patients.

Advanced therapeutic directions to treat the underactive bladder.

Muscarinic agonists are the most commonly used agents for treating the underactive bladder (UAB). However, because of the absence of pharmacologic specificity for bladder-only effects and possibly as a result of degenerative and other post-synaptic changes involving detrusor smooth muscle cells, they are simply not effective and side effects are common. If safe and effective therapy for UAB is made available, then most experts agree that the potential market would exceed industry expectations, just as antimuscarinic agents for overactive bladder did in the late 1990 s. The pharmaceutical and biotechnology industries that have a pipeline to urology and women's health should consider UAB as a potential target condition. A rational approach to treating the pathology of UAB is presented with a discussion of potential targets that may allow the development of safe and effective agents for the treatment of UAB.

Comparison of the discontinuation rates and side-effect profiles of pilocarpine and cevimeline for xerostomia in primary Sjögren's syndrome.

OBJECTIVES: There are currently no head-to-head comparisons of sialagogues for Primary Sjögren's syndrome (pSS). We compared the tolerability and side effect profile of pilocarpine and cevimeline in patients with pSS and determined clinical, laboratory and pathological variables associated with therapeutic failure. METHODS: We retrospectively reviewed the use of pilocarpine and cevimeline in 118 patients with pSS who fulfilled the 2002 American European Consensus Group criteria in a University-based setting. Clinical, laboratory and pathological baseline variables were collected. Failure of therapy was defined as the clinician or patient's decision to stop treatment either due to lack of efficacy or side effects. RESULTS: Cevimeline was associated with lower failure rates compared to pilocarpine among first-time users: 27% vs. 47% (p=0.02), and all users: 32% vs. 61% (p<0.001). Severe sweating was the most frequent side effect leading to cessation of therapy and occurred more frequently in pilocarpine (25%) than cevimeline (11%) users (p=0.02). Patients who previously failed one secretagogue were less likely to discontinue treatment with the other agent, 52% of first-time users vs. 27% of second-time users (p=0.004). Only ANA positivity was associated with failure: [59% vs. 38%] (p=0.03). CONCLUSIONS: pSS patients were more likely to continue cevimeline than pilocarpine long-term due to fewer reported side effects with cevimeline. Therapeutic failure of one secretagogue did not predict similar results with the other since second time users were more likely to continue long-term treatment.

In vivo imaging of mGluR5 changes during epileptogenesis using [11C]ABP688 PET in pilocarpine-induced epilepsy rat model.

INTRODUCTION: Metabotropic glutamate receptor 5 (mGluR5) that regulates glutamatergic neurotransmission contributes to pathophysiology of epilepsy. In this study, we monitored the changes of mGluR5 in vivo using [11C]ABP688 PET during the epileptogenesis in a pilocarpine-induced epilepsy rat model. METHODS: In vivo mGluR5 images were acquired using [11C]ABP688 microPET/CT in pilocarpine-induced chronic epilepsy rat models and controls. We also acquired microPET/CT at acute, subacute as well as chronic periods after status epilepticus. Non-displaceable binding potential (BPND) of [11C]ABP688 was calculated using simplified reference tissue model in a voxel-based manner. mGluR5 BPND of the rat brains of epilepsy models and controls were compared. RESULTS: Status epilepticus developed after pilocarpine administration and was followed by recurrent spontaneous seizures for more than 3 weeks. In chronic epilepsy rat model, BPND in hippocampus and amygdala was reduced on a voxel-based analysis. Temporal changes of mGluR5 BPND was also found. In acute period after status epilepticus, mGluR5 BPND was reduced in the whole brain. BPND of caudate-putamen was restored in subacute period, while BPND of the rest of the brain was still lower. In chronic period, global BPND was normalized except in hippocampus and amygdala. CONCLUSIONS: In vivo imaging of mGluR5 using [11C]ABP688 microPET/CT could successfully reveal the regional changes of mGluR5 binding potential of the rat brain in a pilocarpine-induced epilepsy model. The temporal and spatial changes in mGluR5 availability suggest [11C]ABP688 PET imaging in epilepsy provide abnormal glutamatergic network during epileptogenesis.