Showing 4 results for Water Maze
Mohammad Reza Palizvan, Hajar Rajabian, Elahe Mirzazadeh, Yahya Jand, Ehsan Alah Ghaznavi Rad,
Volume 11, Issue 4 (12-2008)
Abstract
Background: Although the roles of steroid hormones in the activation and maintenance of reproductive function are proved well, emerging evidence indicated that these steroids influence on performance of learning and memory. These effects are complex and vary with task, gender, and age, as well as the regimens of steroid exposure. This study was carried out in order to assess the role of progesterone administration in newborns rats on Morris water maze learning ability after adolescence.
Methods and Materials : This experimental study was carried out on 36 newborns Wistar rats. Rats were divided randomly into 6 groups female progesterone, male progesterone, female sesamoide, male sesamoid rats and male and female control rats. Progesterone groups were treated with a single injection of progesterone (100 mg/kg) and sesamoid groups were received the same volume of sesamoid oil as the progesterone vehicle in day 1 or 2 after brith, 60 days later, spatial memory ability was determined in Morris water maze.
Results : The results of this study show that water maze learning can enhance by administration of sesamoid oil in newborn female pups in compared to progesterone and control groups (p<0.05). In addition, adding progesterone to sesame oil reduce water maze learning to control level.
Conclusion: The hypothesis that progesterone impaired spatial reference memory in female rats was supported by this experiment.
Mahmoud Salami, Gholam Ali Hamidi, Zahra Aghanouri, Mozhgan Dadkhah,
Volume 11, Issue 4 (12-2008)
Abstract
Background: Sensory signals and intrinsic activity of the neuronal circuits deeply influence on developing the sensory systems in early life. Light deprivation of animals is known as an established method in assessment of environmental signals in development of the nervous system. Methods and Materials: In this experimental study eighteen male rats at 75 days of postnatal age were used. The animals were divided in two groups, one reared in a cycle of 12light/12dark (light reared-LR) and the other keep in darkness since birth through experiment (Light deprived- LD). The animals were trained in a Morris water maze for spatial memory. They must navigate the maze until finding a platform hidden 1 cm below of water. Then, the time required and the distance spent to find the platform were measured for assessment of the animal behavior. Each animal was given 4 trials/day and the experiment lasted for 6 days. This stage was followed by probe and postprobe tests to evaluate how the learning is consolidated. Results: The results indicated that, compared to their LD counterparts, the LR group was superior in finding the platform where they required a noticeable shorter time to hit the platform(p<0.009). Also, animals in the LR group steered a shorter distance to find the target than did the LD animals(p<0.034). While the two groups elicited a considerable difference during the first half of the experiment both LR and LD rats demonstrated a similar behavior over the second half of the study. Conclusion: The light deprivation negatively influences the spatial navigation in water maze so that the visually deprived rats show less ability in searching the maze based on the spatial cues.
Zahra Salimi , Lotfollah Khajehpour , Farshad Moradpour , Ahmad Ali Moazedi , Ali Pourmotabbed ,
Volume 22, Issue 3 (8-2019)
Abstract
Background and Aim: Nilutamide is a pure non-steroidal antiandrogen that is used in the treatment of advanced-stage (metastatic) prostate cancer and acts as a potent and selective antagonist of the androgen receptors. Previous studies showed that there must be relationship between androgen receptors and cognitive aspects of the brain. Therefore, it seems that nilutamide affects spatial learning and memory through effect on androgen receptors. The aim of this study is to evaluate the effect of nilutamide on spatial localization in the Morris Water Maze and synaptic plasticity at the hippocampus CA1 area of male adolescent rats.
Materials and Methods: In this experimental study, male Wistar rats were randomly divided into 4 groups (n=9). Experimantal groups received vehicle (DMSO 10%) as control groups and different doses of Nilutamide (5, 10 and 15µg/2.5µl). Drug and vehicle were injected for 4 days before training.
Ethical Considerations: This study with research ethics code
EE/ 97, 24, 3061300/ scu.ac.ir has been approved by research ethics committee at Shahid Chamran University of Ahvaz.
Findings: Analysis showed that escape latency and traveled distance for finding hidden platform in the group which received nilutamide (15µg) were significantly lower than of control group at first (p < 0.05) and second (p < 0.01) training days. The results of field potential recording showed that nilutamide had not any significant effect on fEPSP and PS.
Conclusion: The results of peresent study releaved that i.c.v microinjection of nilutamide improved spatial learninig in first and second days, wherease increase of treatment (4 days) not affected spatial learning.
Fatemeh Heidari Soureshjani, Majid Kheirollahi, Parichehreh Yaghmaei, Fattah Sotoodehnejadnematalahi,
Volume 23, Issue 4 (9-2020)
Abstract
Background and Aim: Alzheimer's Disease (AD) is a neurodegenerative brain disease that gradually destroys memory and cognitive skills. The disease is caused by the formation of beta-amyloid plaques, oxidative stress, dysfunctions in the cholinergic system, neuronal killing inflammation, and ultimately brain atrophy. Donepezil and hyoscyamoside have inhibitory effects on these pathogens; therefore, their impact on the learning process of Alzheimer’s rats in the Morris Water Maze was investigated.
Methods & Materials: In the present experimental study, 60 male rats of Wistar breed with approximately 7 weeks age within the control group (rats that received normal water and food), the PBS group (underwent surgery), PBS group (received solvent Aβ), the first Alzheimer›s group (animals that received beta-amyloid by Alzheimer’s surgery, second Alzheimer’s group (after Alzheimer’s surgery, they received 1 cc of normal saline daily, and treatment groups that treated the rats with beta-amyloid after Alzheimer. In the hyoscyamoside group, they received 10 mg/kg daily of hyoscyamoside for 28 days. The donepezil group received it 4 mg/kg daily for 28 days by gavage. The Morris Water Maze test was used to evaluate learning and memory. Data were analyzed by ANOVA statistical analysis and Post Hoc test.
Ethical Considerations: The Ethics Committee in Biomedical Research, Islamic Azad University, Science and Research Branch approved the research (Code: IR.IAU.SRB.REC 1397.057)
Results: Beta-amyloid injection caused extensive damage to memory. The treatment groups with hyoscyamoside and donepezil spent less time and distance with a significant level (P<0.001) than the group of Alzheimer’s patients to find the hidden platform. In the reminder phase, where the previously hidden platform was located, they spent more time, with a significant level (P<0.001) in the local quarter.
Conclusion: Treatment of rats with hyoscyamoside and donepezil improved spatial memory in Alzheimer’s rats. They appear to play a significant role in the prevention and treatment of Alzheimer’s disease.
