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Water Maze Test (water + maze_test)
Kinds of Water Maze Test Selected AbstractsThe orally combined neuroprotective effects of sodium ferulate and borneol against transient global ischaemia in C57 BL/6J miceJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2010Xiao-hong Chen Abstract Objectives, This study aimed to investigate the possible modification of the neuroprotective effect of sodium ferulate, when orally co-administered with borneol, in transient global cerebral ischaemia-induced functional, histological and cellular alterations in mice. Methods, The bilateral common carotid artery occlusion was conducted in C57 BL/6J mice for 25 min. The mice were then subjected to a water maze test over an extended recovery period, followed by an assessment of neuronal loss in the CA1 region of the hippocampus (haematoxylin and eosin staining). The blood,brain barrier permeability (Evans blue tracing), brain oedema and oxidative stress were assayed and histological sections were also immunostained for gliofibrillar acid protein (GFAP) expression. Key findings, The ischaemia reperfused mice were associated with long-lasting spatial learning deficits in the absence of other behavioural impairments and with neurodegeneration in the hippocampal CA1 region. However, the histological injuries were significantly attenuated by oral co-administration of sodium ferulate and borneol. Furthermore, combined treatment with sodium ferulate and borneol resulted in a significant reduction in brain oedema, GFAP-positive cells, malonaldialdehyde levels and blood,brain barrier permeability, but an increase in superoxide dismutase activity. Conclusions, Borneol may have benefits for the neuroprotective effect of sodium ferulate against injury induced in the brain by ischaemia/reperfusion. [source] The protective effects of melatonin from oxidative damage induced by amyloid beta-peptide 25,35 in middle-aged ratsJOURNAL OF PINEAL RESEARCH, Issue 2 2002Y. X. Shen This work investigated the ability of melatonin to prevent oxidative damage in brain tissue induced by injection of beta-amyloid peptide 25,35 (A,25,35) in middle-aged rats. The Morris water maze was used to evaluate the cognitive function of the rats. Thiobarbituric acid-reactive substances and antioxidative enzymes (superoxide dismutase and glutathione peroxidase) activities were measured. It was found that injection of (A,25,35) (20 ,g) into the rat hippocampus caused an increase in the latency (the time to find the platform), the total swimming distance to the platform, and the starting angles in (A,25,35)-treated rats. Furthermore, a significant rise in lipid peroxidation and decrease in antioxidative enzyme activities in brain tissue were found. Melatonin (0.1, 1, and 10 mg/kg, i.g. × 10 days) improved the spatial resolution of amnesic rats in the Morris water maze test. Meanwhile, melatonin antagonized the lipid peroxidation in both the mitochondria (P < 0.01) at the doses of 0.1, 1.0, and 10 mg/kg and in the cytoplasm at the doses of 0.1 and 1.0 mg/kg. Also in the amnesic rats, melatonin (0.1, 1.0, and 10 mg/kg, i.g. × 10 days) stimulated the antioxidative enzyme activities. The results show that melatonin effectively reduced lipid peroxidation and enhanced the antioxidative enzyme activities in A,25,35 -treated rats, which may contribute to the improvement of rats' learning and memory impaired by A,25,35. [source] Procyanidins extracted from the lotus seedpod ameliorate scopolamine-induced memory impairment in micePHYTOTHERAPY RESEARCH, Issue 12 2009Jiqu Xu Abstract The major purpose of this study was to determine the effect of procyanidins extracted from the lotus seedpod (LSPC) on the learning and memory impairments induced by scopolamine (1 mg/kg, i.p.) in mice. The capacities of memory and learning were evaluated by the Morris water maze and the step-down avoidance test. LSPC (50, 100, 150 mg/kg BW, p.o.) significantly reversed scopolamine-induced learning and memory impairments in the Morris water maze test, as evaluated by shortened escape latency and swimming distance. In the step-down avoidance test, LSPC (50, 100, 150 mg/kg BW, p.o.) treatment significantly reduced the number of errors and shortened latency compared with that of scopolamine. In addition, LSPC was also found to inhibit acetyl cholinesterase (AChE) activity. These results of this study suggest that LSPC may play a useful role in the treatment of cognitive impairment caused by AD and aging. Copyright © 2009 John Wiley & Sons, Ltd. [source] The newly synthesized linoleic acid derivative DCP-LA ameliorates memory deficits in animal models treated with amyloid-, peptide and scopolaminePSYCHOGERIATRICS, Issue 4 2005Tetsu NAGATA Abstract Background:, In our earlier study, 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA), a newly synthesized linoleic acid derivative with cyclopropane rings instead of cis -double bonds, facilitated hippocampal synaptic transmission by stimulating glutamate release from presynaptic terminals as mediated via ,7 acetylcholine (Ach) receptors under the influence of protein kinase C. The present study assessed the possibility of using DCP-LA as a cognitive enhancer in animal models. Methods:, Amyloid-,1,40 peptide (300 pM/day) or saline was continuously injected in the right lateral ventricle of rats for 2 weeks. Then, the water maze test was carried out, once per day for 7 days, 1 h after the intraperitoneal injection with DCP-LA or saline. In a different set of experiments, rats were intraperitoneally injected with scopolamine (1 mg/kg) and the water maze test was performed twice per day, with the first test taking place 1 h after the intraperitoneal injection with DCP-LA, galantamine or saline, and the second test starting 2 min after the end of the first. Results:, Continuous intraventricular injection with amyloid-,1,40 peptide in the rat lateral ventricle prolonged the latency for acquisition in the water maze test. DCP-LA (1 mg/kg, intraperitoneal (i.p.)) significantly improved the impairment, which reached a level similar to the latency for sham. Furthermore, DCP-LA (1 mg/kg, i.p.) significantly ameliorated learning and memory deficits in rats treated with scopolamine and was, if not more, effective than galantamine, a modest inhibitor of acetylcholinesterase with nicotinic ACh receptor modulation. Conclusion:, The results of the present study show that DCP-LA ameliorates learning and memory deficits induced by amyloid-,1,40 peptide or scopolamine. DCP-LA may thus offer new hope for dementia patients. [source] PROTECTIVE EFFECTS OF ICARIIN ON COGNITIVE DEFICITS INDUCED BY CHRONIC CEREBRAL HYPOPERFUSION IN RATSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2009Rui-Xia Xu SUMMARY 1Icariin is a major constituent of flavonoids derived from the Chinese medicinal herb Epimedium revicornum Maxim. The aim of the present study was to investigate whether icariin has protective effects on learning ability and memory in a rat model of chronic cerebral hypoperfusion. 2Chronic cerebral hypoperfusion was induced by permanent ligation of the common carotid artery in Wistar rats for 4 months. One month after permanent artery occlusion, rats were adminitered icariin at doses of 0, 30, 60 or 120 mg/kg per day, p.o., for 3 months. Neurobehavioural and neurobiochemical parameters were examined to evaluate the effects of icariin on cognitive deficits induced by chronic cerebral hypoperfusion. 3The Morris water maze test revealed that learning ability and memory were severely impaired in untreated rats, but were significantly improved in icariin-treated rats. Icariin treatment also ameliorated chronic cerebral hypoperfusion-induced oxidative stress in the brain, as evidenced by reduced malondialdehyde formation and maintained superoxide dismutase activity. In addition, the decreased hippocampal levels of acetylcholine, acetylcholinesterase and choline acetyltransferase associated with chronic cerebral hypoperfusion were significantly prevented by icariin treatment. 4In conclusion, icariin protects against cognitive deficits induced by chronic cerebral hypoperfusion in rats. These effects appear to be mediated through its anti-oxidant effects, as well as its effects on the circulatory and cholinergic systems. [source] Overexpression of APP provides neuroprotection in the absence of functional benefit following middle cerebral artery occlusion in ratsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Jared Clarke Abstract Cerebral ischaemia leads to a transient accumulation of ,-amyloid precursor protein (APP) and ,-amyloid (A,) peptides adjacent to the ischaemic lesion. There is conflicting evidence that APP/A, fragments may either enhance neuronal plasticity or be neurotoxic. The aim of the current study was to assess the effect of overexpression of human APP in rats on functional recovery following cerebral ischaemia. Adult APP-overexpressing (hAPP695 Tg) rats subjected to transient middle cerebral artery occlusion (MCAO) had significantly smaller infarct volumes than non-transgenic littermates, yet did not perform better on a series of sensorimotor or learning tests during a 6-month follow-up period. In fact, transgenic animals were found to be significantly more impaired in both the beam-walking and Morris water maze tests following MCAO. Immunohistochemistry showed human A,-positive staining in the cortex and hippocampus of APP transgenic rats. The present data suggest that while overexpression of APP in rats may provide some histological neuroprotection in the event of cerebral ischaemia, this does not translate into significant functional recovery. [source] Impaired long-term depression in P2X3 deficient mice is not associated with a spatial learning deficitJOURNAL OF NEUROCHEMISTRY, Issue 5 2006Yue Wang Abstract The hippocampus is a brain region critical for learning and memory processes believed to result from long-lasting changes in the function and structure of synapses. Recent findings suggest that ATP functions as a neurotransmitter or neuromodulator in the mammalian brain, where it activates several different types of ionotropic and G protein-coupled ATP receptors that transduce calcium signals. However, the roles of specific ATP receptors in synaptic plasticity have not been established. Here we show that mice lacking the P2X3 ATP receptor (P2X3KO mice) exhibit abnormalities in hippocampal synaptic plasticity that can be restored by pharmacological modification of calcium-sensitive kinase and phosphatase activities. Calcium imaging studies revealed an attenuated calcium response to ATP in hippocampal neurons from P2X3KO mice. Basal synaptic transmission, paired-pulse facilitation and long-term potentiation are normal at synapses in hippocampal slices from P2X3KO. However, long-term depression is severely impaired at CA1, CA3 and dentate gyrus synapses. Long-term depression can be partially rescued in slices treated with a protein phosphatase 1,2 A activator or by postsynaptic inhibition of calcium/calmodulin-dependent protein kinase II. Despite the deficit in hippocampal long-term depression, P2X3KO mice performed normally in water maze tests of spatial learning, suggesting that long-term depression is not critical for this type of hippocampus-dependent learning and memory. [source] | |||||||||||||