AIMTo investigate the effects of oxygen-glucose deprivation on cultured rat hippocampal neurons.

METHODSThe hippocampal neurons cultured for 12 d were exposed to combined oxygen-glucose deprivation for 0.5 - 4 h and then cultured with original medium in normoxia for 28 h. Necrotic neurons were identified by 0.4% trypan blue staining and apoptotic neurons were detected by a TUNEL technique. Meanwhile, the area, perimeter and circle diameter of cell bodies were measured respectively by a photography analysis system.

RESULTSThe percentage of necrotic cells in cultured hippocampal neurons increased significantly during oxygen-glucose deprivation, but the percentage of apoptotic cells increased significantly after 28 h oxygen-glucose recovery. Photography analysis showed that area, perimeter and circle diameter of the necrotic cell bodies were larger than those of the apoptotic ones.

CONCLUSIONOxygen-glucose deprivation can lead to severe damage of cultured hippocampal neurons. The necrosis is major during acute oxygen-glucose deprivation, while the apoptosis is major 28 h after oxygen-glucose recovery.

Animals ; Cell Hypoxia ; Cells, Cultured ; Glucose ; deficiency ; Hippocampus ; cytology ; Neurons ; cytology ; Oxygen ; metabolism ; Rats ; Rats, Wistar

In the adult brain, neural stem cells have been found in two major niches: the dentate gyrus and the subventricular zone [corrected]. Neurons derived from these stem cells contribute to learning, memory, and the autonomous repair of the brain under pathological conditions. Hence, the physiology of adult neural stem cells has become a significant component of research on synaptic plasticity and neuronal disorders. In addition, the recently developed induced pluripotent stem cell technique provides a powerful tool for researchers engaged in the pathological and pharmacological study of neuronal disorders. In this review, we briefly summarize the research progress in neural stem cells in the adult brain and in the neuropathological application of the induced pluripotent stem cell technique.
Hippocampus ; cytology ; metabolism ; Humans ; Induced Pluripotent Stem Cells ; cytology ; metabolism ; Models, Biological ; Neural Stem Cells ; cytology ; metabolism ; transplantation ; Neurodegenerative Diseases ; metabolism ; pathology ; prevention & control ; Neurogenesis ; Signal Transduction

AIMTo observe the intracellular calcium ion spatio-temporal and dynamic changes in the hippocampal neuronal culture model of epilepsy induced by low magnesium ion medium, and to explore the relationship between calcium ion and epilepsy.

METHODSApplying both laser scanning confocal microscope and patch clamp to timely observe the changes of [Ca2+]i and electrophysiological in the hippocampal neuronal culture model of epilepsy, and the influence of NMDA receptor-gated channels retarder and non-NMDA receptor-gated channels retarder.

RESULTSAfter the hippocampal nerve cell broken into epileptiform discharges, [(Ca2+]i rapidly ascended to (620 +/- 70) nmol/L, NMIDA acceptor retarder (MK-801, 10 micromol/L) and non-NMDA acceptor retarder (NBQX, 10 micromol/L) reduced [Ca2+]i ascendance. Recovery of the elevated [Ca2+]i was obviously delay, after 90 min and 150 min epileptiform discharges, it took (114.8 +/- 5.2) min and (135.0 +/- 22.7) min (P < 0.05) respectively.

CONCLUSIONIn vitro status epilepticus causes sustained elevation of intracellular calcium levels in hippocampal neurons

Animals ; Animals, Newborn ; Calcium ; metabolism ; Cells, Cultured ; Hippocampus ; cytology ; metabolism ; Neurons ; metabolism ; Rats ; Rats, Sprague-Dawley ; Status Epilepticus ; metabolism ; physiopathology

OBJECTIVETo observe effects of acupuncture and moxibustion on ultrastructure and silent information regulator 1 (SIR1) in hippocampal neuron mitochondria in rats with Alzheimer's disease (AD) in order to explore its possible effective mechanism during the process of protecting mitochondria.

METHODSEighty Wistar rats were randomly divided into a normal group, a sham operation group, a model group and an acupuncture group, 20 rats in each one. The AD model was established in the model group and acupuncture group with injection of Amyloid beta Protein Fragment1-14 (Abeta1-42) into the hippocampus. Acupuncture and moxibustion was applied at "Baihui" (GV 20) and "Shenshu" (BL 23) in the acupuncture group, once a day, seven days as a treatment course and totally two course were required. The rest groups were all fed with normal diet, without any treatment. The transmission electron microscopy, immunohistochemistry and immunoblotting technique were respectively adapted to measure ultrastructure and level of STR1 in hippocampal neuron mitochondria in AD rats.

RESULTSCompared with the model group, the ultrastructure in hippocampal neuron mitochondria in the acupuncture group was effectively improved. The average optical density of SIR1 in hippocampus was 0.21 +/- 0.10 and the gray value was 136.82 +/- 47.42 in the model group, which were obviously lower than 0.47 +/- 0.09 and 281.44 +/- 57.98 in the normal group (both P < 0.01). However, levels of SIR1 in the acupuncture group, they were 0.32 +/- 0.11 and 199.52 +/- 58.12, which were significantly increased compared with those in the model group (both P < 0.05).

CONCLUSIONThe reinforcing-kidney and regulating-Governor Vessel method of acupuncture and moxibustion for AD could improve ultrastructure of mitochondria and increase levels of SIR1 to achieve the aim of recovering injury of mitochondria and protecting function of mitochondria.

Acupuncture Therapy ; Alzheimer Disease ; metabolism ; prevention & control ; therapy ; Amyloid beta-Peptides ; metabolism ; Animals ; Hippocampus ; cytology ; metabolism ; Humans ; Male ; Mitochondria ; metabolism ; Moxibustion ; Neurons ; cytology ; metabolism ; Rats ; Rats, Wistar

AIMIn order to explore the neurobiological mechanism of morphine addiction and treatment methods, the acute and chronic effects of morphine on the intracellular free calcium concentration ([Ca2+]i) in cultured hippocampal neurons were investigated.

METHODSChanges of [Ca2+]i induced by morphine in primarily cultured hippocampal neurons were measured by confocal laser scanning microscopy using Ca(2+) -sensitive dye fluo-4 as the calcium fluorescent probe.

RESULTSMorphine actually induced the increase in [Ca2+]i of hippocampal neurons. This process could be blocked by naltrindole (delta opioid receptor antagonist) pretreatment, but not by CTOP (micro opioid receptor antagonist) pretreatment. Pretreatment of the cells with thapsigargin almost completely blocked morphine-evoked response; while pretreatment of the cells with verapamil partially inhibited this response. After exposure to 100 micromol/L morphine for 24 h, intracellular [Ca2+]i increased and the increase could be intensified after adding 10 micromol/L naloxone to the medium.

CONCLUSIONMorphine induced the release of Ca2+ is mainly from inositol 1, 4, 5-trisphosphate (IP3) sensitive stores in hippocampal neuron of rats through activation of delta2 subtype opioid receptor.

Animals ; Calcium ; metabolism ; Cells, Cultured ; Hippocampus ; cytology ; Male ; Microscopy, Confocal ; Morphine ; pharmacology ; Neurons ; cytology ; drug effects ; Rats ; Rats, Wistar

AIMTo evaluate the effects of different doses of zinc on the expression of metallothionein isoforms in stressed hippocampal neurons in vitro.

METHODSThe cell stress model was developed by corticosterone. The cultured hippocampal neurons were assigned to seven groups as follows: control group, zinc deficiency group, and their corresponding stressed groups, as well as three different levels of zinc complementarity groups.

RESULTSIn zinc deficiency group, the expressions of metallothionein and MT-1 mRNA, MT-3 mRNA were downregulated. On the other hand, inductions of metallothionein and it's mRNAs in stressed zinc complementarity group were increased. In addition, the levels of supernatant IL-6 and NO were increased clearly in zinc deficiency group and corticosterone stressed groups.

CONCLUSIONOur results suggest that zinc deficiency may decrease while zinc complementarity increase the expressions of metallothioneins and MT-1 mRNA, MT-3 mRNA in stressed hippocampal neurons in vitro.

Animals ; Animals, Newborn ; Hippocampus ; cytology ; metabolism ; In Vitro Techniques ; Metallothionein ; metabolism ; Neurons ; metabolism ; RNA, Messenger ; Rats ; Zinc ; pharmacology

AIMTo observe the effect and mechanism of scopolamine on morphine(Mor)-induced mice dependence.

METHODSThe Mor-dependent mice model was established by intraperitoneal (ip) administered Mor for seven days. Pain threshold, times of jump and hippocampus intracellular free calcium ion concentration ([Ca2+]i) were determined by the heat plate test, naloxone (Nal)-precipitated jumping response and flow cytometry, respectively.

RESULTSThe pain threshold of Mor-dependent mice decreased significantly while there was a marked increase in times of jump, the rate of jumping animals and hippocampus [Ca2+]i. Co-administered scopolamine, the pain threshold of Mor-dependent mice increased significantly; the number of jump, the rate of jumping animals and hippocampus [Ca2+]i all decreased significantly.

CONCLUSIONScopolamine could antagonize the Mor-induced mice dependence, which could be related to decreasing the levels of brain intracellular free calcium.

Animals ; Calcium ; metabolism ; Hippocampus ; cytology ; drug effects ; metabolism ; Mice ; Mice, Inbred Strains ; Morphine ; pharmacology ; Morphine Dependence ; metabolism ; Scopolamine Hydrobromide ; pharmacology

OBJECTIVETo study the effect of chronic noise exposure on expression of N-methyl-D-aspartic acid receptor 2B (NR2B) and tau phosphorylation in hippocampus of rats.

METHODSTwenty-four male SD rats were divided in control group and chronic noise exposure group. NR2B expression and tau phosphorylation in hippocampus of rats were detected after chronic noise exposure (100 dB SPL white noise, 4 h/d×30d) and their mechanisms underlying neuronal apoptosis in hippocampus of rats with TUNEL staining.

RESULTSThe NR2B expression decreased significantly after chronic noise exposure which resulted in tau hyperphosphorylation and neural apoptosis in hippocampus of rats. Immunohistochemistry showed that the tau hyperphosphorylation was most prominent in dentate gyrus (DG) and CA1 region of rat hippocampus.

CONCLUSIONThe abnormality of neurotransmitter system, especially Glu and NR2B containing NMDA receptor, and tau hyperphosphorylation in hippocampus of rats, may play a role in chronic noise-induced neural apoptosis and cognition impairment.

Animals ; Apoptosis ; Hippocampus ; cytology ; metabolism ; Male ; Neurons ; cytology ; metabolism ; Noise ; adverse effects ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; metabolism ; tau Proteins ; metabolism

Animals ; Calcium ; metabolism ; Cell Hypoxia ; Cells, Cultured ; Hippocampus ; cytology ; Neurons ; drug effects ; metabolism ; Rats ; Rats, Wistar ; omega-Conotoxins ; pharmacology

To investigate the effects of ischemia-reperfusion on the levels of nitric oxide and nitric oxide synthase isoforms (nNOS and iNOS), rat organotypic hippocampus slice were cultured in vitro and subjected to ischemia by oxygen-glucose deprivation (OGD) for 30 min and then placed in the normal culture condition. The ischemia-reperfusion produced a time-dependent increase in nitrite levels in the culture medium. Reverse transcriptional-polymerase chain reaction showed augmented levels of mRNA for both nNOS and iNOS when compared with control at 12 h and remained increase at 36 h after OGD (P < 0.05). The protein levels of both nitric oxide synthase isoforms increased significantly as determined by Western Blot. OGD also caused neurotoxicity in this model as revealed by the elevated lactate dehydrogenase (LDH) efflux into the incubation solution. The results suggest that organotypic hippocampus slice is a useful model in studying ischemia-reperfusion brain injury. NO and NOS may play a critical role in the ischemia-reperfusion brain damage in vitro.
Animals, Newborn ; Cell Hypoxia ; Hippocampus/cytology ; Hippocampus/*metabolism ; Nitric Oxide/*metabolism ; Nitric Oxide Synthase Type I/*metabolism ; Nitric Oxide Synthase Type II/*metabolism ; RNA, Messenger/metabolism ; Rats, Sprague-Dawley ; Reperfusion Injury/*metabolism ; Tissue Culture Techniques