جستجوی مقالات مرتبط با کلیدواژه "radial maze" در نشریات گروه "پزشکی"

Food restriction may have beneficial or detrimental effects on the brain functions such as learning and memory. Also, dopamine receptors are involved in learning and information retrieval. This study was performed to determine the simultaneous effect of food restriction and dopamine D2 receptor inhibition on spatial memory of rats.

In this experimental study, 60 male Wistar rats were allocated into 6 groups including controls, 25%, 50% and 75%, food restriction, sulpiride (D2 receptor antagonist, 4 mg/kg/day, ip), 75% food restriction and sulpiride and treated for 21 days. To evaluate the memory, an eight-point radial arm maze was used. Then, the catalase and malondialdehyde level of the hippocampus were measured.

Twenty-five percent food restriction caused to 11.8 percent decrease in spending time to find the food compared to control group (P<0.05). The 75% food restriction and or sulpiride injection significantly increased that time by 24.4% and 18.3%, respectively (P<0.05). The group with 75% food restriction were received sulpiride showed the most increase in the time of food finding compared to all groups (P<0.05). Catalase activity was only significantly reduced in the 75% restricted groups to 17.6% and 22.2%, respectively (P<0.05). Malondialdehyde production was significantly increased in the 75% food restricted groups to 50.2% and 59.3, respectively and sulpiride-received group to 31.2% compared to the control group (P<0.05).

Simultaneous applying of food restriction and inhibition of dopamine D2 receptors resulted in increased hippocampal prooxidant levels and exacerbated memory impairment.

Introduvtion: Alzheimer's disease is one of the most common neurodegenerative diseases in the brain. The aim of this study was to evaluate the effect of lovastatin and folic acid on cognitive deficit by induced lesion in nucleus basalis magnocellularis
In this experimental study, 56 male Wistar rats were randomly divided into 8 groups: (7 rat in each group): control(intact), Nucleus basalis magnocellularis (NBM) lesion group, which received electrically- induced lesion (0.5 m A, 3s) in NBM, Sham group ( the electrode was impaled in to the NBM with no lesion), lovastatin group (NBM lesion lovastatin 1mg/kg), folic acid group (NBM lesion folic acid 5mg/kg), interaction group( NBM lesion lovastatin-folic acid), saline group( NBM lesion saline) and Dimethyl sulfoxide (DMSO) group (NBM lesion DMSO 5%). Acquisition and retention testing was done by using an eight-radial arm maze, in which, the patterns of arm entries in each group for calculating working memory errors, reference memory error and latency were recorded. Data were analyzed using one-way ANOVA and Tukey's post hoc test
Results showed that there was a significant difference between the control and lesion groups in the parameters of the reference memory error, working memory error and elapsed time (P˂ 0.05). Co-administration of lovastatin - folic acid resulted in a reduction in the reference and working memory error and the time spent in the eight-arm radial laser maze compared with lesion group
According to the results, co-administration of folic acid and lovastatin had a positive effect on spatial memory of Alzheimer's rats.

Oxidative stress causes damage in processes, such as learning and memory through affecting the nervous system. Also, using chemical drugs for treatment of stress-induced depression is often associated with attenuation of memory. In the present study, the effect of hydroalcoholic extract of Noroozak (Salvia leriifolia) root as an antioxidant along with antidepressant drug, fluvoxamine, were investigated on the spatial memory of male rats under immobilization stress.
In this experimental study, 25 adult male rats (mean weight, 170g), were randomly divided into five groups of 5 each. The animals were orally treated with different doses of drug and extract for 21 days. At the end of the treatment period, a radial 8-arm maze was used to investigate the behavioral indices. Also, malondialdehyde and catalase levels in the brain tissue homogenate and glucose and cortisol levels in blood, were measured. Data analysis was carried out using one-way analysis of variance and post-hoc Tukey’s test.
Spatial memory in the rats under immobilization stress (sham group) showed a significant decrease as compared to the control group. Administration of extract of Noroozak root improved the spatial memory in the groups receiving extract and extract-drug compared to sham and fluvoxamine groups. Also, the extract of Noroozak root improved the flovoxamine-induced attenuation of memory, increased catalase, and decreased malondialdehyde, glucose, and cortisol in the groups under treatment with extract and extract-drug compared to sham group.
The findings showed that immobilization stress and fluvoxamine administration for the treatment of stress-induced depression resulted in attenuation of spatial memory; while, the extract of Noroozak root improved memory in all groups due to powerful antioxidant property.

Alzheimer’s disease (AD) is a neurodegenerative disorder characterized clinically by progressive memory loss and subsequent dementia. The aim of this study was to evaluate the synergist effect of folic acid and vitamin B12 on spatial memory in adult male rat Alzheimer's disease.
Material and In this experimental study, 49 male Wistar rats were randomly divided into 7 groups: (7 rats in each group): control(intact), NBM lesion group, which received electrically- induced lesion (0.5 m A, 3s) in NBM, sham group ( the electrode was impaled in to the NBM with no lesion), NBM lesion folic acid 5mg/kg, NBM lesion vitamin B12 5mg/kg, NBM lesion folic acid- vitamin B12, NBM lesion saline. Acquisition and retention testing was done by using an eight-radial arm maze, in which the patterns of arm entries were recorded in each group for calculating working memory errors, reference memory error ,and latency. Data were analyzed using one-way ANOVA and Tukey's post hoc test.
The results showed that there was a significant difference between the control and lesion groups in the parameters of the reference memory error, working memory error ,and elapsed time (P˂0.05). The administration of folic acid and vitamin B12alone did not have any significant effect on spatial memory parameters compared with the lesion group. Co-administration folic acid- vitamin B12 resulted in a reduction in the reference and working memory errors and the time spent in the eight-arm radial laser maze.
According to the results, the NMB lesion resulted in a reduction in spatial memory and co-administration of folic acid and vitamin B12 resulted in improved spatial memory.

Statins, inhibitors of 3-hydroxy-3-methyl glutaryl coenzyme A reductase, are widely used as medication to lower cholesterol levels in human patients. Much evidence indicates that statins can also exert neuroprotective actions. So, this study aimed at examining the effect of lovastatin on cognition deficit induced by bilateral electrical lesion of nucleus basalis magnocellularis (NBM) in the Alzheimer’s disease model in adult male rats.
In this experimental study, 56 adult male wistar rats were divided into 8 groups (n=7): control (intact), NBM lesion group (which received electrically- induced lesion 0.5 mA in 3s), sham group (the electrode was impaled into the NBM with no lesion(, lovastatin groups (lesion, 5, 10, 20 mg/kg) and DMSO 5% group (NBM lesion ೄ 5%). Acquisition and retention testing was done by using an eight-radial arm maze in which the patterns of arm entries were recorded for calculating working memory errors, reference memory error and latency in each group.
The bilateral NBM lesion resulted in significant reduction of spatial memory in acquisition and retention tests in the form of increased working and reference memory errors compared to the control group (P The electrical NBM lesion can reduce spatial memory function and the lovastatin therapy after brain injury improved cognitive disorders. It seems that lovastatin by reducing the activity of the acetylcholinesterase enzyme and increasing acetylcholine transferase enzyme activity can cause improvement in learning and memory capability.

Cinnamom (Cinnamonum verum) has therapeutic effects such as anti-diabetic, decreasing of weight and blood lipid and sugar. The aim of this study was to evaluate the effect of aqueous extract of Cinnamon on learning and spatial memory in streptozotocin-induced diabetic rats.
In this study, 28 adult male Wistar rats weighting 200 ± 30 g were used. Rats were divided into four groups: control (C), control receiving extract (C), diabetic (D), diabetic receiving extract (D). Diabetes was induced by intraperitoneal injection of 50 mg/kg streptozotocin. The experiments were assigned to 3 weeks. In this time, the treatment of extract was carried out in a dose of 200 mg/kg. At the end of experiment the weight of the treated rats was compared to control groups. Evaluation of learning and spatial memory was done using radial eight-arm maze. The data were analyzed using repeated measure ANOVA by SPSS software.
Findings: The significant (P The aqueous extract of cinnamon attenuates the learning and the spatial memory of diabetic rats, probably due to increase of blood sugar and its destructive effects on nervous system function.