Arachidonylcyclopropylamide (ACPA) State-Dependent Memory: Involvement of Dorsal Hippocampal 5-HT1A Receptors
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Count: 1 Abstract ID: 16 subject: Cognition: Learning and Memory Presentation Type: Poster Arachidonylcyclopropylamide (ACPA) state-dependent memory: Involvement of dorsal hippocampal 5-HT1A receptors Submission Author: Majid JafariSabet Majid JafariSabet1 1. Department of Pharmacology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Background and Aim : The crucial role of cannabinoidergic and serotonergic systems of the hippocampus in modulation of memory has already been raised. The present study purposed to investigate the possible role of the dorsal hippocampal 5-HT1A serotonergic system upon arachidonylcyclopropylamide (ACPA) state-dependent memory (SDM). Methods : The dorsal hippocampal CA1 regions of adult male NMRI mice were bilaterally cannulated, and serotonergic agents were microinjected into the intended sites of injection. A single-trial step-down inhibitory avoidance task was used for the assessment of memory retrieval and state of memory in adult male NMRI mice. Results : Post-training and/or pre-test administration of a selective cannabinoid CB1 receptor agonist, ACPA (0.1 and 0.2 mg/kg, i.p.) dose-dependently induced amnesia. Pre-test injection of the same doses of ACPA reversed the post-training ACPA-induced amnesia. This event has been named ACPA SDM. Pre-test microinjection of a 5-HT1A receptor agonist, 8-OH-DPAT (0.5 and 1 μg/mouse) impaired memory retention, although the low dose of the drug (0.25 μg/mouse) did not affect memory retention. Pre-test administration of a 5-HT1A receptor antagonist, (S)-WAY-100135 (1 and 2 μg/mouse) improved memory retention, although the low dose of the drug (0.5 μg/mouse) did not affect memory retention. Pre-test microinjection of 8-OH-DPAT (0.125 and 0.25 μg/mouse) reversed the memory impairment induced by post- training administration of ACPA (0.2 mg/kg, i.p.). Moreover, pre-test administration of 8-OH- DPAT (0.125 and 0.25 μg/mouse) with an ineffective dose of ACPA (0.05 mg/kg, i.p.) significantly restored the retrieval and induced ACPA SDM. Pre-test administration of 8-OH- DPAT (0.0625, 0.125 and 0.25 μg/mouse) by itself cannot affect memory retention. In other series of experiments, pre-test microinjection of (S)-WAY-100135 (0.25 and 0.5 μg/mouse) 5 min before the administration of ACPA (0.2 mg/kg, i.p.) dose dependently inhibited ACPA SDM. Pre-test administration of (S)-WAY-100135 (0.125, 0.25 and 0.5 μg/mouse) by itself cannot affect memory retention. Conclusion : It may be proposed that the 5-HT1A receptors in the dorsal hippocampal region play a crucial role in ACPA SDM. Keywords : ACPA; 8-OH-DPAT; (S)-WAY-100135; Dorsal hippocampus; State-dependent memory Count: 2 Abstract ID: 26 subject: Cognition: Learning and Memory Presentation Type: Poster Cognitive Reserve in Female Patients with Multiple Sclerosis: Myth or Reality? Submission Author: Sara Yazdani Sara Yazdani1, Mohsen Foroughipour 2 1. Ph.D. Linguistics department, Ferdowsi University of Mashhad, Mashhad, Iran 2. Neurology Department, Mashhad University of Medical Sciences, Mashhad, Iran Background and Aim : Multiple sclerosis (MS) is a demyelinating disorder that, according to studies, specifically manifests in women, three times more than men. Along with physical and emotional problems, MS patients have to deal with cognitive difficulties. However, the question here is whether MS patients suffer from cognitive complications equally in different stages or some remain intact? Cognitive reserve shows that some patients have maintained their cognitive abilities in task processing allow them to deal better than others with the brain damage. On account of the importance of this matter and its impact on patients’ quality of life, the purpose of the present study is to evaluate the cognitive non-verbal semantic task performance in individuals with MS to measure their cognitive reserve. Methods : In this cross-sectional study, 68 female patients with definite relapsing-remitting multiple sclerosis and 68 age, gender, and educationally-matched healthy controls were selected using convenient sampling based on inclusion criteria. The patients aged from 20 to 50 years (M=29.14, SD=4.81), their years of education ranged from 12 to 18 (M=14.83, SD=1.69). The patients were divided into two groups according to their Expanded Disability Status Scale (EDSS), their Montreal Cognitive Assessment (MoCA), and their total disease duration. The EDSS of the first group of patients (N=34) ranged from 0-4 (M=2.01, SD=0.98) showed they were fully ambulatory, less cognitively impaired (M=22.61, SD=1.77) with their total disease duration ranged within 10 years of expected symptom onset (M=5.39, SD=1.83). Whereas the EDSS scores of the second group (N=34) ranged from 4.5-6.5 (M=5.45, SD= 0.65) illustrated they had more physical disabilities, higher cognitive dysfunction (M=17.17, SD=16.96) and with their total disease duration ranged more than 10 years of expected symptom onset (M=12.85, SD= 1.23). The participants had no history of neurological disorders other than MS, drug and/or alcohol abuse, brain surgery, psychiatric disorder, and uncorrected visual or auditory problems. The picture version of The Camel and Cactus Test (CCT) was selected and administered to evaluate MS patients’ ability to figure out the semantic associations. This test is an improved and difficult form of the Palm and Pyramid Trees test (PPT). Results : The results of the study showed there were statistically significant differences between groups in MoCA, and significant differences in EDSS and disease duration between patient groups (p < 0.05). Nevertheless, the results of the one-way ANOVA test showed that there was no statistically difference between groups (F (2,133) = 2.055, p = 0.132). Conclusion : The findings of this study showed disregarding the degree of neuropathology seen in MS patients (such as high EDSS scores, low cognitive function, and longer disease duration), they might be able to reserve their cognitive performance in tasks such as nonverbal semantic test. Keywords : cognitive reserve; non-verbal semantic task; multiple sclerosis; relapsing- remitting; females Count: 3 Abstract ID: 177 subject: Cognition: Learning and Memory Presentation Type: Poster Evaluation of the effects of epidermal neural crest stem cells transplantation on impairment of learning & memory in a rat model of vascular dementia Submission Author: Somayeh Akbari Somayeh Akbari1, Masoud Haghani2, Mahnaz Bayat3, Etrat hooshmandi4 1. Department of Physiology, The Medical School, Shiraz University of Medical Sciences, Shiraz, Iran 2. Department of Physiology, The Medical School, Shiraz University of Medical Sciences, Shiraz, Iran 3. Clinical Neurology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran 4. Clinical Neurology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran Background and Aim : Vascular dementia (VaD) is regarded as the loss of cognitive function and impairments of memory resulting from cerebral blood vessels disease. It is known that a moderate but chronic reduction in regional cerebral blood flow leads to the development of dementia and neurodegeneration by increasing the free radical formation and proinflammatory cytokines. These in turn impair the function of neuronal cells and contribute to brain lesions and cognitive decline.The stem cell therapy is an alternative strategy in the treatment of neurological disorders. Furthermore, the epidermal neural crest stem cells (EPI-NCSCs) have attracted great attention for cell-based therapies. EPI-NCSCs are characterized by high degree of plasticity, easy access sources, good self-renewal capacity and high expandation speed, which makes them a good option for transplantation. However, there have been no reports on the effect of the EPI-NCSC VaD rat’s model. In the present study, we tested the hypothesis that EPI-NCSCs administered intravenously reverse 2VO-induced cognitive impairments. Methods : The 40 adult male Sprague-Dawly rats weighing 250-300 g were used in this study. The rats were randomly divided into 4 groups: intact control, sham-operated, 2VO + V (bilateral carotid vessel occlusion + vehicle) and 2VO + EPI-NCSC transplanted groups. In this study, we occluded the bilateral carotid arteries of rats surgically to induce chronic cerebral hypoperfusion. Approximately 2×106cells in 300 μl medium as a 3-course infusion (on days 4, 14, 21 after the surgery) were transplanted into 2VO+EPI-NCSC group via the tail vein. The open field and passive avoidance tests were used for evaluating the anexiety-like behavior and learning & memory, respectively. Results : Although all groups learned the avoidance test with the same number of foot shocks but the passive avoidance memory was significantly impaired in 2VO group (37.7 ± 13.5; P < 0.001) compared to the sham (279 ± 21) , control (290 ± 7.23) and 2VO+ EPI-NCSC (269.42 ± 27.08 ) groups. However, the epidermal neural crest stem cells transplantation in 2VO+EPI- NCSC group restores the memory to the comparable value of sham and control groups. The open field test results indicate that in the 2VO+V group the number of grooming increased (15.65± 2.13; P < 0.001), which was significantly higher respect to the control (6 ± 2.13), sham (8.7 ± 2.76) and 2VO + EPI-NCSC (6 ± 2.07) groups. However, our data indicated that there has been a marked improvement in the number of grooming in 2VO+EPI-NCSC rats. In addition, there was no significant difference observed between groups in the time spent in border and center regions of open field test. Conclusion : Our findings demonstrated that EPI-NCSC could reverse 2VO-induced cognitive impairments and may provide an important basis for the application of stem cell transplantation to treatment of VD. Keywords : Vascular dementia, EPI-NCSC, PRP, memory, learning. Count: 4 Abstract ID: 105 subject: Cognition: Learning and Memory Presentation Type: Poster Effect of Fish oil treatment during lactation period on Novel Object Recognition task in the offspring of male rats affected by neonatal hypoxia Submission Author: Nima Badripour Nima Badripour1, Zohreh Ghotbeddin*2, Zahra Basir3, Shima Balalidehkordi4 1.