@2024 Afarand., IRAN

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ISSN: 2252-0805    The Horizon of Medical Sciences 2014;20(1):23-27

Background
From various areas of the brain, Hippocampus area has a very important role concerning memory, learning and fixing any kind of memory [1, 2, 3]. Brain ischemia disrupts brain’s activity and makes an increase in brain oxidants in the lipid peroxidation process [4, 5]. By trapping free radicals, antioxidants cause the body to detoxify [9]. Flavonoid compounds, including Gallic acid, are of powerful antioxidants [10].
Previous Studies
Brain ischemia results in severe loss of memory [11]; and oxidative stresses cause inflammatory reactions [12], while Gallic acid prevents these reactions [13]. Gallic acid has antioxidant effect [14].
Aim(s)
The aim of this study was to assess the effect of Gallic acid on level of passive avoidance memory among mature female rats, under brain’s bilateral ischemic conditions.
Research type
Method of the study is experimental.
Research society, place and time
Research society was the population of mature female rats with mean weight 200 gr to 250 gr (Animal Reproduction and Breeding Center, Ahwaz University of Medical Sciences, Iran). The study was conducted in Islamic Azad University, Fars Science and Research Branch.
Sampling method and number
84 mature female rats were studied. The animals were under 12 hour darkness, 12 hour light, and temperature20-22℃ conditions; they were fed with compressed food and water (Pars Tehran, Iran). The rats were randomly divided into 6 groups of 14, as follows: Control (C; without any manipulation of carotid artery and treatment) Gallic Acid Control (CGA; without any manipulation of carotid artery and with Gallic acid treatment) Ischemia Control (CI; with manipulation of carotid artery, but without obstruction and without treatment) Ischemia (I; complete and bilateral obstruction of carotid arteries and without treatment) Solvent Ischemia (IS; complete and bilateral obstruction of carotid arteries under normal saline gavage) Gallic Acid Ischemia (IGA; complete and bilateral obstruction of carotid arteries under Gallic acid gavage) For ischemia conditions, after 8 hours of food deprivation, the animals were anesthetized. Then, creating a gap in the ventral neck and removing adipose tissue and thyroid, carotid arteries were obstructed by means of skin suture instruments and with tight knot around vessels. All prescriptions were applied for 10 days, and after that avoidance memory test was performed. To habituate, the animals were placed in the light part behind the guillotine door, and after 30 seconds with animal’s head turning towards the door, the guillotine door was slowly opened allowing the animal to enter the dark part. Immediately after that, the door was closed. Then, the animal was taken from the dark part and it was transferred into a cage. This step was repeated in 3 stages, after 30 minutes. 30 minutes after adaptation session, learning acquisition was conducted. The animals were placed in the light part. After 30 seconds, the guillotine door was opened. The animal entering the dark part, the door was closed and one mA shock was applied in the animal’s feet for 5 seconds with 50 Hz frequency. Then, allowing the animal to exit from the dark place, after 30 seconds it was taken from the light part and it was returned to the cage. After 2 minutes, if the animal’s behavior was as its own behavior before the experiment and there was no entrance into the dark part for 2 seconds, successful acquisition was registered. Nevertheless, if this was not so, the door was closed and the animal received a shock for second time. 24 hours, 72 hours, and 7 days after training, the rats were tested for retrieval test; in this manner that at first the animals were put in the light part, and after 30 seconds, the guillotine door being opened, time latency before the first entrance into the dark part (Strep-Through Latency; STL) was measured and registered for various groups. Higher STL showed a stronger memory.
Used devices&materials
To assess passive avoidance learning behavior, Shuttle Box device (Kimia Kahroba-ye-mobin; Iran) was used. The device is composed of “training box” and “control box”. Data were analyzed, by the use of One-way Variance Analysis test (in order to assess differences between groups), LSD Support test (in order to compare each pair of groups), and SPSS 18 software.
Findings by Text
24 hours, 72 hours, and 7 days after applying electrical shock, STL time for each of the groups I and IS had a significant decrease than CI group. 24 hours, 72 hours, and 7 days after applying electrical shock, STL time for IGA group had a significant increase than group I. 72 hours after applying electrical shock, STL time for CGA group had a significant increase than CI group. 7 days after applying electrical shock, STL time for IGA group had a significant decrease than CI group.
Main comparison to the similar studies
Non-declared
Suggestions
Non-declared
Limitations
Non-declared
Conclusions
Gallic acid results in increasing passive avoidance memory in rats with brain ischemia.
Acknowledgments
The researchers feel grateful to Research Deputy of Islamic Azad University, Fars Science and Research Branch, and officials of Research Center of Ahwaz University of Medical Sciences.
Conflict of interest
Non-declared
Ethical Permissions
The research’s protocol was prepared according to international laws for care of laboratory animals; and ethic committee of the university approved it.
Funding Sources
Non-declared

TABLES and CHARTS

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