ABSTRACT
Background and aim: Our environment is exposed to electromagnetic fields by development and industrialization of life. The aim of this investigation was to evaluate the effects of extremely low frequency electromagnetic fields [5 and 25 Hz] during fetal life on adulthood learning in male rat
Methods: In this study forty eight Sprague Dawley pregnant rats [150+/-20g] were divided into six groups of eight: control, sham, and 5 or 25Hz and 50 or 500micro T. Duration of exposure was 4 hours per day [continuously from 8 to 12 A.M.] from first day to 15th day of gestation. We evaluated learning, body weight, brain weight, brain volume, brain weight to body weight ratio and brain density of 60 days-old male offsprings. The learning task was performed by shuttle box in the form of one-way active avoidance conditioning. The number of conditioning responses and latency periods was recorded. Data was statistically analyzed by Kruskal-wallis test
Results: Fetal life exposure to ELF EMF [25Hz/50micro T] improved learning, decreased body weight and increased brain weight to body weight ratio in male rat [P<0.05]. Fetal life exposure to 25 Hz/500 micro T, 5 Hz/500 micro T and 5 Hz/50 micro T increased body weight
Conclusion: Fetal life exposure to ELF EMF [25Hz/50micro T] could improve learning in male rats
ABSTRACT
Reports on agmatine are controversial showing that it may improve memory, it can deteriorate memory and some did not notice any interference with learning and memory. In the present study, the effect of directly intra-CA1 agmatine microinjection on water maze learning and memory has been assessed. The cannuls were implanted in hippocampal CA1 regions of rats in a sterotaxic frame after general anesthesia. After one week recovery period, the animals were assessed in the reference memory version of water maze. Agmatine [1, 10, 100 or 200 microg/0.5 microl] or saline were infused 20 minutes before or immediately after training. Agmatine-treated rats did not show any significant difference neither in water maze acquisition nor in consolidation task in comparison with control and sham groups. Agmatine does not affect water maze learning and memory
ABSTRACT
Diabetes mellitus is a common metabolic disorder that associates with structural and functional changes in central and peripheral nervous system and progressive decline in cognitive abilities. Recent experimental and clinical data suggested that C-peptide replacement during type 1 diabetes exerts beneficial effects on diabetic rats. Determine the effect of intraperitoneal [IP] injection of c-peptide on cognitive dysfunction in type 1 diabetic rats. 24 male Sprague dawly rats [230-300 gr] used for this project divided into 3 groups: 1. control group, 2. type 1 diabetic group and 3. Diabetic group that receive C-peptide [25 nmol/kg/daily for 28 day/IP]. Diabetes induced with IV injection of Streptozotocin [60mg/kg]. Twenty one days after onset of diabet, behavioral tests conducted for seven days. In reference memory assessment, the latency of finding platform during four days decline significantly in all groups [P<0.05]. Mean escape time in diabetic group was significantly longer in comparison to other groups [P<0.05] but in comparison to diabetic group with C-peptide group, memory impairement decline significantly [P< 0.05]. During three days of working memory test, the latency required for finding platform decreased significantly [P<0.05] but this time was longer in diabetic group [P<0.05]. C-peptide could improve memory in diabetic group. C-peptide had significant role in control and inhibition of memory disorder progression