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Antiepileptogenic agents that prevent the development of epilepsy following a brain insult remain the holy grail of epilepsy therapeutics. We have employed a label-free proteomic approach that allows quantification of large numbers of brain-expressed proteins in a single analysis in the mouse (male C57BL/6J) kainate (KA) model of epileptogenesis. In addition, we have incorporated two putative antiepileptogenic drugs, postsynaptic density protein-95 blocking peptide (PSD95BP or Tat-NR2B9c) and a highly selective inducible nitric oxide synthase inhibitor, 1400W, to give an insight into how such agents might ameliorate epileptogenesis. The test drugs were administered after the induction of status epilepticus (SE) and the animals were euthanized at 7 days, their hippocampi removed, and subjected to LC-MS/MS analysis. A total of 2,579 proteins were identified; their normalized abundance was compared between treatment groups using ANOVA, with correction for multiple testing by false discovery rate. Significantly altered proteins were subjected to gene ontology and KEGG pathway enrichment analyses. KA-induced SE was most robustly associated with an alteration in the abundance of proteins involved in neuroinflammation, including heat shock protein beta-1 (HSP27), glial fibrillary acidic protein, and CD44 antigen. Treatment with PSD95BP or 1400W moderated the abundance of several of these proteins plus that of secretogranin and Src substrate cortactin. Pathway analysis identified the glutamatergic synapse as a key target for both drugs. Our observations require validation in a larger-scale investigation, with candidate proteins explored in more detail. Nevertheless, this study has identified several mechanisms by which epilepsy might develop and several targets for novel drug development. OPEN PRACTICES: This article has been awarded Open Data. All materials and data are publicly accessible as supporting information. Learn more about the Open Practices badges from the Center for Open Science: https://osf.io/tvyxz/wiki.
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Amidinas/administración & dosificación , Anticonvulsivantes/administración & dosificación , Bencilaminas/administración & dosificación , Epilepsia/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Péptidos/administración & dosificación , Animales , Epilepsia/inducido químicamente , Ácido Kaínico/administración & dosificación , Masculino , Ratones Endogámicos C57BL , Proteómica , Estado Epiléptico/inducido químicamente , Estado Epiléptico/metabolismoRESUMEN
Facilitating activation, or delaying inactivation, of the native Kv7 channel reduces neuronal excitability, which may be beneficial in controlling spontaneous electrical activity during epileptic seizures. In an effort to identify a compound with such properties, the structure-activity relationship (SAR) and in vitro ADME for a series of heterocyclic Kv7.2-7.5 channel openers was explored. PF-05020182 (2) demonstrated suitable properties for further testing in vivo where it dose-dependently decreased the number of animals exhibiting full tonic extension convulsions in response to corneal stimulation in the maximal electroshock (MES) assay. In addition, PF-05020182 (2) significantly inhibited convulsions in the MES assay at doses tested, consistent with in vitro activity measure. The physiochemical properties, in vitro and in vivo activities of PF-05020182 (2) support further development as an adjunctive treatment of refractory epilepsy.
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Descubrimiento de Drogas , Epilepsia/tratamiento farmacológico , Activación del Canal Iónico/efectos de los fármacos , Canal de Potasio KCNQ2/metabolismo , Piperidinas/farmacología , Pirimidinas/farmacología , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Electrochoque , Humanos , Canal de Potasio KCNQ2/agonistas , Microsomas/efectos de los fármacos , Estructura Molecular , Piperidinas/administración & dosificación , Piperidinas/química , Pirimidinas/administración & dosificación , Pirimidinas/química , Ratas , Relación Estructura-ActividadRESUMEN
The purpose of this study was to understand and compare patient and staff perceptions of a video-based preparatory education tool for head and neck radiotherapy. Patients and staff completed a questionnaire assessing their perceptions of whether the education tool was relevant, clear, complete and reassuring. Staff rated the video's accuracy and anticipated impact on future patient information needs. Demographic information was collected. Open-ended questions were used to elicit additional feedback. Quantitative responses from 50 patients and 48 staff were very positive and not significantly different between the two groups. Content analysis of the qualitative data provided insight into the information and approaches valued by patients and staff and how these differed. Staff members were more critical of the production quality and completeness of information related to procedures and treatment side effects. Patients valued seeing procedures acted out and desired more information about what these experiences would feel like and how to engage in self-care. Although staff-driven development may be an effective method of designing the content and approach of a preparatory education video, care should be taken to consider differences between patient and staff perceptions of information needs.
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Recursos Audiovisuales , Neoplasias de Cabeza y Cuello/radioterapia , Educación en Salud/métodos , Personal de Salud/psicología , Evaluación de Necesidades , Educación del Paciente como Asunto , Pacientes/psicología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Personal de Salud/educación , Humanos , Masculino , Persona de Mediana Edad , Participación del Paciente , Pronóstico , Investigación CualitativaRESUMEN
Intracranial electroencephalography (EEG) is commonly used to study epileptogenesis and epilepsy in experimental models. Chronic gliosis and neurodegeneration at the injury site are known to be associated with surgically implanted electrodes in both humans and experimental models. Currently, however, there are no reports on the impact of intracerebral electrodes on proteins in the hippocampus and proinflammatory cytokines in the cerebral cortex and plasma in experimental models. We used an unbiased, label-free proteomics approach to identify the altered proteins in the hippocampus, and multiplex assay for cytokines in the cerebral cortex and plasma of C57BL/6J mice following bilateral surgical implantation of electrodes into the cerebral hemispheres. Seven days following surgery, a repeated low dose kainate (KA) regimen was followed to induce status epilepticus (SE). Surgical implantation of electrodes reduced the amount of KA necessary to induce SE by 50%, compared with mice without surgery. Tissues were harvested 7 days post-SE (i.e., 14 days post-surgery) and compared with vehicle-treated mice. Proteomic profiling showed more proteins (103, 6.8% of all proteins identified) with significantly changed expression (p < 0.01) driven by surgery than by KA treatment itself without surgery (27, 1.8% of all proteins identified). Further, electrode implantation approximately doubled the number of KA-induced changes in protein expression (55, 3.6% of all identified proteins). Further analysis revealed that intracerebral electrodes and KA altered the expression of proteins associated with epileptogenesis such as inflammation (C1q system), neurodegeneration (cystatin-C, galectin-1, cathepsin B, heat-shock protein 25), blood-brain barrier dysfunction (fibrinogen-α, serum albumin, α2 macroglobulin), and gliosis (vimentin, GFAP, filamin-A). The multiplex assay revealed a significant increase in key cytokines such as TNFα, IL-1ß, IL-4, IL-5, IL-6, IL-10, IL12p70, IFN-γ, and KC/GRO in the cerebral cortex and some in the plasma in the surgery group. Overall, these findings demonstrate that surgical implantation of depth electrodes alters some of the molecules that may have a role in epileptogenesis in experimental models.
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BACKGROUND AND PURPOSE: Functional brain imaging using genetically encoded Ca2+ sensors in larval zebrafish is being developed for studying seizures and epilepsy as a more ethical alternative to rodent models. Despite this, few data have been generated on pharmacological mechanisms of action other than GABAA antagonism. Assessing larval responsiveness across multiple mechanisms is vital to test the translational power of this approach, as well as assessing its validity for detecting unwanted drug-induced seizures and testing antiepileptic drug efficacy. EXPERIMENTAL APPROACH: Using light-sheet imaging, we systematically analysed the responsiveness of 4 days post fertilisation (dpf; which are not considered protected under European animal experiment legislation) transgenic larval zebrafish to treatment with 57 compounds spanning more than 12 drug classes with a link to seizure generation in mammals, alongside eight compounds with no such link. KEY RESULTS: We show 4dpf zebrafish are responsive to a wide range of mechanisms implicated in seizure generation, with cerebellar circuitry activated regardless of the initiating pharmacology. Analysis of functional connectivity revealed compounds targeting cholinergic and monoaminergic reuptake, in particular, showed phenotypic consistency broadly mapping onto what is known about neurotransmitter-specific circuitry in the larval zebrafish brain. Many seizure-associated compounds also exhibited altered whole brain functional connectivity compared with controls. CONCLUSIONS AND IMPLICATIONS: This work represents a significant step forward in understanding the translational power of 4dpf larval zebrafish for use in neuropharmacological studies and for studying the events driving transition from small-scale pharmacological activation of local circuits, to the large network-wide abnormal synchronous activity associated with seizures.
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Encéfalo , Pez Cebra , Animales , Encéfalo/diagnóstico por imagen , Neuroimagen Funcional , Larva , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológicoRESUMEN
OBJECTIVES: Although it is widely acknowledged that radiotherapy treatments can have a negative impact on a patient's sexual health, this aspect of side effect management is not commonly addressed by radiation therapists or by other cancer specialists. It is important for radiation therapists to recognize and address possible sexual health issues to provide a holistic approach to care. This quality-improvement project was designed to help radiation therapists discuss the sexual health needs of patients undergoing radiotherapy by improving their clinical knowledge, skills, and comfort level about the topic. METHODS: This study used a cross-sectional descriptive prequestionnaire/postquestionnaire design, in which data were collected from a nonrandom sample of radiation therapists at a single urban radiation therapy center. Participants attended two 90-minute sexual health education workshops specifically designed for radiation therapists and completed online preworkshop/postworkshop questionnaires. All questions were quantitative in nature. The survey consisted of multiple-choice, multiple-select, and five-point Likert-scale questions. Descriptive analysis was used for data analysis. RESULTS: The results of this improvement project indicated that participants had introductory-level knowledge about how cancer treatments can impact patients' sexual health. Although there is potential for some changes in the general knowledge levels of the participants after the initiative, two general workshops about the topic are not enough to have radiation therapists feel comfortable enough with the topic to change their clinical practice. CONCLUSION: This project identified that although radiation therapists acknowledge the importance of discussing sexual health concerns as part of delivering holistic health care, lack of knowledge and expertise with the topic is a main barrier to initiating conversations. To help prepare radiation therapists, education and training initiatives, which build on knowledge and offer opportunities to develop and apply practical skills in both simulated and real-life situations, should be created. This can help to increase confidence in the sexual health counseling provided, which may result in more radiation therapists frequently engaging in these important sexual health conversations.
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Actitud del Personal de Salud , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud , Neoplasias/radioterapia , Salud Sexual , Personal de Salud/educación , Personal de Salud/psicología , Humanos , Calidad de la Atención de Salud , Calidad de Vida , Radiología/organización & administraciónRESUMEN
Regulatory guidelines recommend specialised safety pharmacology assessments in animals to characterise drug-induced effects on the central nervous system (CNS) prior to first-in-human trials, including the functional observational battery or Irwin test (here collectively termed neurofunctional assessments). These assessments effectively detect overtly neurotoxic drugs; however, the suitability of the in vivo assessments to readily detect more subtle drug effects on the nervous system has been questioned. A survey was formulated by an international expert working group convened by the (NC3Rs) to capture practice in CNS neurofunctional assessment tests and opinions on the perceived impact of in vivo test battery endpoints. Impact was defined as "the impact of measures alone/in combination on decision making in drug development or candidate selection when using the neurofunctional assessment". The results demonstrate that rodents are predominantly used for small molecule assessments, whereas non-rodents are frequently used to test biotherapeutics. Practice varied between respondents in terms of experimental design. Subsets of test battery endpoints were consistently considered highly impactful (e.g. convulsions, stereotypic behaviors); however, the perceived impact level of other endpoints varied depending whether drugs were designed for CNS targets. Many endpoints were considered to have no or minimal impact, whereas a subset of endpoints in CNS test batteries appears more impactful than others. A critical evaluation is required to assess whether the translational value of CNS in vivo safety pharmacology assessments could be increased by modifying or augmenting standard CNS test batteries. A revised approach to CNS safety assessment has the potential to reduce animal numbers without compromising patient safety.
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Desarrollo de Medicamentos/métodos , Evaluación Preclínica de Medicamentos/métodos , Modelos Animales , Farmacología/métodos , Animales , Sistema Nervioso Central/efectos de los fármacos , Desarrollo de Medicamentos/legislación & jurisprudencia , Desarrollo de Medicamentos/estadística & datos numéricos , Evaluación Preclínica de Medicamentos/estadística & datos numéricos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Humanos , Farmacología/legislación & jurisprudencia , Proyectos de Investigación/legislación & jurisprudencia , Proyectos de Investigación/estadística & datos numéricos , Encuestas y CuestionariosRESUMEN
BACKGROUND: The ActualHCA™ system continuously monitors the activity, temperature and behavior of group-housed rats without invasive surgery. The system was validated to detect the contrasting effects of sedative and stimulant test agents (chlorpromazine, clonidine and amphetamine), and compared with the modified Irwin test (mIT) with rectal temperature measurements. METHODS: Six male Han Wistar rats per group were used to assess each test agent and vehicle controls in separate ActualHCA™ recordings and mIT. The mIT was undertaken at 15, 30â¯mins, 1, 2, 4 and 24â¯h post-dose. ActualHCA™ recorded continuously for 24â¯h post-dose under 3 experimental conditions: dosed during light phase, dark phase, and light phase with a scheduled cage change at the time of peak effects determined by mIT. RESULTS: ActualHCA™ detected an increase stimulated activity from the cage change at 1-2â¯h post-dose which was obliterated by chlorpromazine and clonidine. Amphetamine increased activity up to 4â¯h post-dose in all conditions. Temperature from ActualHCA™ was affected by all test agents in all conditions. The mIT showed effects on all 3 test agents up to 4â¯h post-dose, with maximal effects at 1-2â¯h post-dose. The maximal effects on temperature from ActualHCA™ differed from mIT. Delayed effects on activity were detected by ActualHCA™, but not on mIT. CONCLUSIONS: Continuous monitoring has the advantage of capturing effects over time that may be missed with manual tests using pre-determined time points. This automated behavioural system does not replace the need for conventional methods but could be implemented simultaneously to improve our understanding of behavioural pharmacology.
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Conducta Animal/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Locomoción/efectos de los fármacos , Animales , Estimulantes del Sistema Nervioso Central/farmacología , Masculino , Ratas , Ratas WistarRESUMEN
Measuring the activity and temperature of rats is commonly required in biomedical research. Conventional approaches necessitate single housing, which affects their behavior and wellbeing. We have used a subcutaneous radiofrequency identification (RFID) transponder to measure ambulatory activity and temperature of individual rats when group-housed in conventional, rack-mounted home cages. The transponder location and temperature is detected by a matrix of antennae in a baseplate under the cage. An infrared high-definition camera acquires side-view video of the cage and also enables automated detection of vertical activity. Validation studies showed that baseplate-derived ambulatory activity correlated well with manual tracking and with side-view whole-cage video pixel movement. This technology enables individual behavioral and temperature data to be acquired continuously from group-housed rats in their familiar, home cage environment. We demonstrate its ability to reliably detect naturally occurring behavioral effects, extending beyond the capabilities of routine observational tests and conventional monitoring equipment. It has numerous potential applications including safety pharmacology, toxicology, circadian biology, disease models and drug discovery.
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Conducta Animal , Vivienda para Animales , Conducta Social , Temperatura , Grabación en Video/métodos , Animales , Automatización , Implantes Experimentales , Masculino , Movimiento , Dispositivo de Identificación por Radiofrecuencia , Ratas Wistar , Reproducibilidad de los Resultados , Factores de TiempoRESUMEN
Approximately 30% of epilepsy patients do not respond to antiepileptic drugs, representing an unmet medical need. There is evidence that neuroinflammation plays a pathogenic role in drug-resistant epilepsy. The high-mobility group box 1 (HMGB1)/TLR4 axis is a key initiator of neuroinflammation following epileptogenic injuries, and its activation contributes to seizure generation in animal models. However, further work is required to understand the role of HMGB1 and its isoforms in epileptogenesis and drug resistance. Using a combination of animal models and sera from clinically well-characterized patients, we have demonstrated that there are dynamic changes in HMGB1 isoforms in the brain and blood of animals undergoing epileptogenesis. The pathologic disulfide HMGB1 isoform progressively increased in blood before epilepsy onset and prospectively identified animals that developed the disease. Consistent with animal data, we observed early expression of disulfide HMGB1 in patients with newly diagnosed epilepsy, and its persistence was associated with subsequent seizures. In contrast with patients with well-controlled epilepsy, patients with chronic, drug-refractory epilepsy persistently expressed the acetylated, disulfide HMGB1 isoforms. Moreover, treatment of animals with antiinflammatory drugs during epileptogenesis prevented both disease progression and blood increase in HMGB1 isoforms. Our data suggest that HMGB1 isoforms are mechanistic biomarkers for epileptogenesis and drug-resistant epilepsy in humans, necessitating evaluation in larger-scale prospective studies.
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Epilepsia/sangre , Proteína HMGB1/metabolismo , Adolescente , Adulto , Anciano , Animales , Antiinflamatorios/farmacología , Anticonvulsivantes/farmacología , Biomarcadores/sangre , Encéfalo/metabolismo , Evaluación Preclínica de Medicamentos , Resistencia a Medicamentos , Epilepsia/tratamiento farmacológico , Femenino , Proteína HMGB1/genética , Humanos , Masculino , Persona de Mediana Edad , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Curva ROC , Ratas Sprague-Dawley , Adulto JovenRESUMEN
PURPOSE: The purpose of this study was to use a survey tool to measure the level of patient satisfaction with current health care delivery in the radiation therapy department, and provide insight into how the department can improve quality of care. METHODS: An anonymous patient satisfaction survey was distributed to radiation therapy patients near the end of their course of treatment. The survey was distributed over a 1-month timeframe to outpatients more than 18 years of age receiving a radical course of treatment. RESULTS: One hundred forty-five surveys were distributed, and 80 surveys were returned for a response rate of 55%. Patients were satisfied with their experience in terms of environmental features such as the waiting rooms and treatment rooms, accessibility and convenience of treatment including wait times, and the interpersonal relationships and clinical competence of the care providers. Results showed a variation in the use of support services depending on the treatment site. CONCLUSION: The survey tool was useful in showing that overall, patients were satisfied with the care in the radiation therapy department at the Princess Margaret Cancer Centre. The survey was also useful for comparing patients' opinions between treatment site groups. The survey responses provided few ideas for improvement strategies. For future directions, the survey may be distributed at regular intervals as a method of measuring levels of patient satisfaction on an ongoing basis.
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The C57BL/6J mouse as a model of seizure/epilepsy is challenging due to high mortality and huge variability in response to kainate. We have recently demonstrated that repeated administration of a low dose of kainate by intraperitoneal route can induce severe status epilepticus (SE) with 94% survival rate. In the present study, based on continuous video-EEG recording for 4-18 weeks from epidurally implanted electrodes on the cortex, we demonstrate that this method also induces immediate epileptogenesis (<1-5 days post-SE). This finding was based on identification of two types of spontaneous recurrent seizures; behavioral convulsive seizures (CS) and electrographic nonconvulsive seizures (NCS). The identification of the spontaneous CS, stage 3-5 types, was based on the behaviors (video) that were associated with the EEG characteristics (stage 3-5 epileptiform spikes), the power spectrum, and the activity counts. The electrographic NCS identification was based on the stage 1-2 epileptiform spike clusters on the EEG and their associated power spectrum. Severe SE induced immediate epileptogenesis in all the mice. The maximum numbers of spontaneous CS were observed during the first 4-6 weeks of the SE and they decreased thereafter. Mild SE also induced immediate epileptogenesis in some mice but the CS were less frequent. In both the severe and the mild SE groups, the spontaneous electrographic NCS persisted throughout the 18 weeks observation period, and therefore this could serve as a chronic model for complex seizures. However, unlike rat kainate models, the C57BL/6J mouse kainate model is a unique regressive CS model of epilepsy. Further studies are required to understand the mechanism of recovery from spontaneous CS in this model, which could reveal novel therapeutic targets for epilepsy.
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Electroencefalografía/métodos , Estado Epiléptico/fisiopatología , Telemetría/métodos , Grabación en Video/métodos , Animales , Anticonvulsivantes/farmacología , Diazepam/farmacología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Inyecciones Intraperitoneales , Ácido Kaínico/administración & dosificación , Ácido Kaínico/toxicidad , Masculino , Ratones Endogámicos C57BL , Monitoreo Fisiológico/métodos , Índice de Severidad de la Enfermedad , Estado Epiléptico/inducido químicamente , Estado Epiléptico/prevención & control , Factores de TiempoRESUMEN
A refined kainate (KA) C57BL/6J mouse model of status epilepticus (SE) using a repeated low dose (RLD) of KA (5 mg/kg, intraperitoneal; at 30 min intervals) was compared with the established single high dose (SHD) of KA (20 mg/kg, intraperitoneal) model. In the RLD group, increased duration of convulsive motor seizures (CMS, Racine scale stage ≥3) with a significant reduction in mortality from 21% to 6% and decreased variability in seizure severity between animals/batches were observed when compared to the SHD group. There was a significant increase in the percentage of animals that reached stage-5 seizures (65% versus 96%) in the RLD group. Integrated real-time video-EEG analysis of both groups, using NeuroScore software, revealed stage-specific spikes and power spectral density characteristics. When the seizures progressed from non-convulsive seizures (NCS, stage 1-2) to CMS (stage 3-5), the delta power decreased which was followed by an increase in gamma and beta power. A transient increase in alpha and sigma power marked the transition from NCS to CMS with characteristic 'high frequency trigger' spikes on the EEG, which had no behavioral expression. During SE the spike rate was higher in the RLD group than in the SHD group. Overall these results confirm that RLD of KA is a more robust and consistent mouse model of SE than the SHD of KA mouse model.
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Conducta Animal/efectos de los fármacos , Ácido Kaínico/administración & dosificación , Estado Epiléptico/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Electroencefalografía/métodos , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
INTRODUCTION: We have evaluated the ability of a semi-automated, optomotor reflex method to assess drug-induced visual dysfunction, in albino and pigmented rats and mice. METHODS: Male Han Wistar (HW) and Long Evans (LE) rats and mice (CD-1 and C57BL/6) were tested in a chamber formed by 4 computer monitors displaying a rotating vertical grating, to elicit head-tracking movements. The highest visible grating frequency was taken as the threshold of visual acuity, in cycles per degree (c/d). Animals received an intravenous infusion of either sodium iodate (50mg/kg) or 0.9% w/v NaCl (aq). They were tested 2h later, then re-tested daily for a further 3 days. The time course of the effect was assessed in HW rats over a 6-week period, including electron microscopy, and immunohistochemical analysis of markers of injury and repair in the retina. RESULTS: Baseline visual acuities for HW and LE rats were 0.355 ± 0.007 and 0.530 ± 0.004 c/d, respectively, and 0.296 ± 0.003 c/d and 0.370 ± 0.001 c/d for CD-1 and C57BL/6 mice, respectively (n=10 for each). In HW rats there was a dramatic loss of visual acuity 2h after administration of sodium iodate (0.021 ± 0.021 c/d; P<0.001). Less dramatic decreases in visual acuity were seen in LE rats and in the two mouse strains. In HW rats, visual acuity was restored after 4 weeks. This paralleled the histopathological recovery of the peripheral retina, whereas the central retina did not recover. DISCUSSION: The method proved to be very convenient, and the stability of visual acuity in vehicle control rats over a 6-week period also demonstrated its suitability for inclusion in long-term toxicity studies. Both albino and pigmented mice and rats are suitable for assessment of retinotoxicity using this method, but albino rats are the most sensitive to sodium iodate.