Neurogenesis by Activation of Inherent Neural Stem Cells in the Rat Hippocampus after Cerebral Infarction

Objective To investigate the changes of neural stem cells (NSCs) in the rat hippocampus after cerebral infarction (CI) and to evaluate the neurogenesis caused by the activation of NSCs. Methods CI models of rats were made and rats were assigned to 6 groups: sham-operated, 1 day, 3 days, 7 days, 14 days, and 28 days after CI. The dynamic expression of bromodeoxyuridine (BrdU), polysialylated neural cell adhesion molecule (PSA-NCAM), glial fibrillary acidic protein (GFAP), and neuronal nuclear antigen (NeuN) were determined by immunohistochemistry and immunofluorescence staining. BrdU was used to mark the proliferated NSCs. PSA-NCAM was used to mark the plasticity of activated NSCs. GFAP and NeuN were used to mark the differentiated NSCs. Results Compared with the controls, the number of BrdU+ cells in the hippocampus increased significantly at 1 day after CI (P<0.05), reached peak at 7 days after CI (P<0.05), decreased but still elevated compared with the controls at 14 days after CI (P<0.05), and nearly unchanged at 28 days after CI. The number of BrdU+/PSA-NCAM+ cells increased significantly at 7 days after CI (P<0.05), reached peak at 14 days after CI (P<0.05), and decreased but still elevated compared with the controls at 28 days after CI (P<0.05). The number of BrdU+/PSA-NCAM+ cells was equal to 60% of the number of BrdU+ cells in all the same period. The number of BrdU+/NeuN+ cells in the hippocampus increased significantly at 14 days after CI (P<0.05) and reached peak at 28 day after CI (P<0.05). The number of BrdU+/GFAP+cells in the hippocampus nearly unchanged after CI. Conclusion CI can stimulate the proliferation of inherent NSCs, and most proliferated NSCs may differentiate into neurons and represent neural plasticity.

Expression changes of hippocampal energy metabolism enzymes contribute to behavioural abnormalities during chronic morphine treatment

Dependence and impairment of learning and memory are two well-established features caused by abused drugs such as opioids. The hippocampus is an important region associated with both drug dependence and learning and memory. However, the molecular events in hippocampus following exposure to abused drugs such as opioids are not well understood. Here we examined the effect of chronic morphine treatment on hippocampal protein expression by proteomic analyses. We found that chronic exposure of mice to morphine for 10 days produced robust morphine withdrawal jumping and memory impairment, and also resulted in a significant downregulation of hippocampal protein levels of three metabolic enzymes, including Fe-S protein 1 ofNADH dehydrogenase, dihydrolipoamide acetyltransferase or E2 component of the pyruvate dehydrogenase complex and lactate dehydrogenase 2. Further real-time quantitative PCR analyses confirmed that the levels of the corresponding mRNAs were also remarkably reduced. Consistent with these findings, lower ATP levels and an impaired ability to convert glucose into ATP were also observed in the hippocampus of chronically treated mice. Opioid antagonist naltrexone administrated concomitantly with morphine significantly suppressed morphine withdrawal jumping and reversed the downregulation of these proteins. Acute exposure to morphine also produced robust morphine withdrawal jumping and significant memory impairment, but failed to decrease the expression of these three proteins. Intrahippocampal injection of D-glucose before morphine administration significantly enhanced ATP levels and suppressed morphine withdrawal jumping and memory impairment in acute morphine-treated but not in chronic morphine-treated mice. Intraperitoneal injection of high dose of D-glucose shows a similar effect on morphine-induced withdrawal jumping as the central treatment. Taken together, our results suggest that reduced expression of the three metabolic enzymes in the hippocampus as a result of chronic morphine treatment contributes to the development of drug-induced symptoms such as morphine withdrawal jumping and memory impairment.

The effects of Shuxuetong on the pathology of cerebral ischemia-reperfusion injury and GABA and TNF-α expression in gerbil models

Objective To study the protective effect and mechanism of Shuxuetong on gerbil brain tissue from the area of ischemia-reperfusion. Methods Cerebral ischemia-reperfusion animal model by transient clipping bilateral common carotid arteries in gerbils. Pathological changes in the hippocampal tissue were observed at different reperfusion time （12 h, 3 d, 7 d）. The expression levels of GABA and TNF-α in the hippocampal CA1 subfield were observed using immunohistochemitry at 12 h, 3 d after reperfusion. The difference of above indices among false operation group, ischemia-reperfusion group and treatment group were compared. Results The injuries of pathology to hippocampal area in ischemia-reperfusion group were more serious than treatment group. The expression levels of GABA in treatment group were significantly increased compared with ischemia-reperfusion group, but the expression levels of TNF-α between the two groups have no difference. Conclusion Shuxuetong has protective effect on brain tissue of ischemia-reperfusion by enhancing the expression of GABA in the hippocampal tissue.

Dual Isoflurane-induced Preconditioning Improves Neuroprotection in Rat Brain In Vitro and the Role of Extracellular Signal-regulated Protein Kinase

Objective To test the ability of isoflurane-induced preconditioning against oxygen and glucose dep- rivation （OGD） injury in vitro. Methods Rat hippocampal slices were exposed to 1 volume percentage （vol%）, 2vo1% or 3vo1% isoflurane respectively for 20 minutes under normoxic conditions （95% O2/5% CO2） once or twice （12 slices in each group） before OGD, with 15-minute washout after each exposure. During OGD experiments, hippocampus slices were bathed with artificial cerebrospinal fluid （ACSF） lacking glucose and perfused with 95% N2 and 5% CO2 for 14 minutes, followed by a 30-minute reperfusion in normal ACSF. The CA1 population spike （PS） was measured and used to quantify the degree of neuronal function recovery after OGD. To assess the role of mitogen-activated protein kinases （MAPKs） in isoflurane preconditioning, U0126, an inhibitor of extracellular signal-regulated protein kinase （ERK1/2）, and SB203580, an inhibitor of p38 MAPK, were used before two periods of 3vol% isoflurane exposure. Results The degree of neuronal function recovery of hippocampal slices exposed to 1 vol%, 2vol%, or 3vol% isoflurane once was 41.88%±9.23%, 55.05%±11.02%, or 63.18%±10.82% respectively. Moreover, neuronal function recovery of hippocampal slices exposed to 1 vol%, 2vo1%, or 3vo1% isoflurane twice was 53.75%±12.04%, 63.50%±11.06%, or 76.25%±12.25%, respectively. Isoflurane preconditioning increased the neuronal function recovery in a dose-dependent manner. U0126 blocked the preconditioning induced by dual exposure to 3vo1% isoflurane （6.13%±1.56%, P〈0.01） and ERK1/2 activities. Conclusions Isoflurane is capable of inducing preconditioning in hippocampal slices in vitro in a dose-dependent manner, and dual exposure to isoflurane with a lower concentration is more effective in triggering preconditioning than a single exposure. Isoflurane-induced neuroprotection might be involved with ERK 1/2 activities.

Activation and subcellular distribution of ERK1/2 following cerebral ischemia/reperfusion in rat hippocampus

Objective： To investigate the activation （phosphorylation） and subcellular localization of extracellular signal-regulated kinase （ERK1/2）, as well as the possible mechanism, following cerebral ischemia and ischemia/reperfusion in rat hippocampus. Methods： Transient brain ischemia was induced by the four-vessel occlusion method in Sprague-Dawley rats. Western blot analysis. Results： During cerebral ischemia without reperfusion ERK1/2 activation immediately increased with a peak at 5 min and then decreased in the cytosol fraction, which was paralleled by the increase of ERK1/2 activation in the nucleus fraction. During reperfusion, ERK1/2 was activated with peaks occurring at 10 min in the cytosol and at 30 min in the nucleus, respectively. Under those conditions, the protein expressions had no significant change. In order to clarify the possible mechanism of ERK1/2 activation, the rats were intraperitoneally administrated with N-methyl-D-aspartate （NMDA） receptor antagonist dextromethorphan （DM）, L-type voltage-gated Ca^2＋ channel （L-VGCC） antagonist nifedipine （ND） 20 rain before ischemia, finding that DM and ND markedly prevented ERK1/2 activation of nucleus fraction induced by reperfusion, not by ischemia. Conclusion： These results suggested that the nuclear translocation mainly occurred during ischemia, while ischemia-reperfusion induced ERK1/2 activation both in the cytosol and the nucleus. Two type calcium channels contributed, at least partially, to the activation of ERK1/2.

Effects of motilin in the hippocampus on the interdigestive migrating motor complex in rats

Objective ：To explore the effects of motilin in the hippocampus on the interdigestive migrating motor complex （MMC） in rats. Methods： Adult SD rats of either sex were used; 0.5 μl motilin （0. 74 retool/L） was injected into the guide cannula which was stereotaxically implanted into the hippocampus previously. Then the MMC was recorded by a RM6240B multilead physiological recording system. Resuits： （1）MMC characteristics of normal rats＇ duodenum： the frequency of phase Ⅲ was （18. 1±0. 4） bursts/min; the amplitude of phase Ⅲ was （260.5±42.3）μV; the duration of phase Ⅲ was （354.1±21.6） s; MMC cycle duration was （690.2±58.7）s. （2） After motilin was injected into the hippocampus, the duodenal MMC cycle duration was decreased significantly. However, the amplitude of phase Ⅲ and the frequency of phase Ⅲ were increased. But there were no effects on the duration of phase Ⅲ . Frequency of phase Ⅲ percentage change was much more than amplitude of phase Ⅲ percentage change （57.2±2.8 vs 39.3±5. 2）. （3） Effects of motilin in the hippocampus on MMC were completely abolished by subdiaphragmal vagotomy. （4） Effects of motilin in the hippocampus on MMC were unaffected by intravenously injected atropine, phentolamine or propranolol. （5） The anti-motilin serum partly abolished the effects of motilin in the hippocampus on MMC. Conclusion： Motilin in the hippocampus has effects on the duodenal MMC cycle duration, the amplitude of phase Ⅲ and the frequency of phase Ⅲ. Motilin in the hippocampus plays an important role in duodenal MMC.

EFFECT OF VASOPRESSIN ON DELAYED NEURONALDAMAGE IN HIPPOCAMPUS FOLLOWING CEREBRALISCHEMIA AND REPERFUSION IN GERBILS

Mongolian gerbils were used as delayed neuronal damage (DNDi animal models. At the end of 15Abstract:Mongolian gerbils were used as delayed neuronal damage (DND)animal models. At the end of 15 minute cerebral ischemia and at various reperfusion time ranging from 1 to 96 hours, the content of water and arginine vasopressin (AVP) in the CA1 sector of hippocampus were measured by the specific gravity method and radioimmunoassay. Furthermore, we also examined the effect of intracerebroventricular (ICV) injection of AVP, AVP antiserum on calcium, Na+, K+-ATPase activrty in the CA1 sector after ischemia and 96 hour reperfusion. The results showed that AVP contents of CA1 sector of hippocampus during 6 to 96 hour recirculation, and the water content of CA1 sector during 24 to 96 hour were significantly and continuously increased. After ICV inJection of AVP, the water content and calcium in CA1 sector of hippocampus at cerebral ischemia and 96 hour recirculation further increased, and the Na+, K+- ATPase activity in CA1 sector was remarkably decreased as compared with that of control. While ICV injection of AVP antiserum, the water content and calcium in CA1 sector were significantly decreased as com pared with that of control. These suggested that AVP was involved in the pathophysiologic process of DND in hippocampus following cerebral ischemia and reperfusion. Its mechanism might be through the change of intracellular action mediated by specific AVP receptor to lead to Ca ions over-load of neuron and inhibit the Na+, K+- ATPase activity , thereby to exacerbate the DND in hippocampus.

EFFECT OF ELECTROACUPUNCTURE ON SYNAPTIC PLASTICITY OF HIPPOCAMPAL NEURONS IN CEREBRAL ISCHEMIA RATS

Objective: To observe the effect of electroacupuncture (EA) on synaptic structure of hippocampal nerve felts and synaptophysin(SYN)expression in rats with cerebral ischemic injury. Methods: Sixty Wistar rats were randomized into sham-operation group, cerebral ischemia (CI) group and EA group, each of which was further divided into 1week (W) and 5W subgroups. CI injury model was established by occlusion of the bilateral common carotid arteries. 'Baihui'(百会 GV 20), 'Dazhui' (大椎 GV 14), 'Renzhong'(人中 GV 26) and 'Guangyuan'(关会 CV 4) were punctured and stimulated electrically. The brain tissue sections containing hippocampus region were stained with immu nohistochemical technique and observed under light microscope and transmission electronic microscope. Results: After CI, the ischemic injury as degeneration of the presynapse compositions, decrease of the synaptic numeral density, and low expression of SYN were observed in hippocampal CA1 area. By the 5th week after CI, the neonatal synapses of Cl and EA groups appeared, and SYN expression was upregulated. In EA group, the recovery of the numeral density of synapses was especially noticeable, being 93.8% of that of sham-operation group and significantly higher than that in Cl group (P<0.01). Compared with sham-operation group, the calibrated optical density (COD) values of SYN increased to 70% in CI group, and 93.3% in EA group, and COD value in EA group was significantly higher than that in Cl group (P<0.01). Conclusion: EA can function in promoting synaptic regeneration and enhancing and perfecting the actions of the reconstructed synapses in hippocampal CA1 area in Cl rats.

EFFECT OF ELECTROACUPUNCTURE ON GENE EXPRESSION OF α- SUBUNIT OF Go-PROTEIN IN THE HIPPOCAMPUS OF RATS WITH HYPERTENSIVE CEREBRAL HEMORRAGE

Objective: To observe the effect of electroacupuncture (EA) on gene expr ession o f α subunit of Go-protein in the brain of rats with hypertensive cerebral hem or rage and study its underlying mechanisms of EA in ameliorating cerebral hemorrag e. Methods: A total of 130 SD rats were randomly divided into nor mal control gro up (n=10), sham operation group (n=40), model group (n=40) and EA group (n=40). The latter 3 groups were further divided into 6 h, 24 h, 48 h and 72 h (tim e course s) subgroups, with 10 rats being in each subgroup. The hypertensive cerebral hem orrage model was induced by injecting 1 μL of collagenase (0.5 U/μL collagena se Type Ⅶ) and heparin (7 U/μL) into the caudate nucleus in rats with renovascul ar hypertension (by clipping the bilateral renal arteries). The gene expression of α subunit of Go-protein in the hippocampus tissue of rats was detected with No rthern blotting hybridization analysis. EA (continuous waves, 120 pulses/min in frequency, 1 mA in intensity and duration of 30 min) was applied to "Shuigou" (水沟 GV 26), bilateral "Neiguan"(内关 PC 6) and bilateral "Housanli"(Zusanl i, 足三里 ST 36). Results: The gene expression of α subunit of Go-protein in th e hippocampus tis sue of the rats was obviously downregulated in hypertensive cerebral hemorrage m odel group and significantly upregulated after EA treatment wit h the extension of time. Conlusion: EA may relieve cerebral hemorr age by regulating the gene transcription of α subunit of Go-protein and incre asing the expression of Go-α protein. This may be one of the molecular mechani sm s of EA in improving hypertensive cerebral hemorrhage.

Surgical menopause enhances hippocampal amyloidogenesis following global cerebral ischemia

Background： Prematurely menopausal women have a doubled lifetime risk of dementia and a 5-fold increased risk of mortality from neuro- logical disorders, but the molecular mechanisms underlying these risks remain unclear. We hypothesized that ischemia-induced amyloidogenesis may be enhanced in the hippocampus following prolonged loss of ovarian 17β-estradiol （E2）, which could contribute to these phenomena. Methods： The current study used a rat model of premature surgical menopause （10-week bilateral ovariectomy） with E2 therapy either initiated immediately （short-term E2 deprivation （STED）） or delayed to the end of the ovariectomy period （long-term E2 deprivation （LTED））. One week after continuous, subcutaneous E2 therapy, we subjected animals to 10-min global cerebral ischemia （GCI） to assess the effect of LTED on ischemia-induced amyloidogenesis in the hippocampal CA1. Results： The present study revealed that while hippocampal β-amyloid （Aβ） is not typically enhanced following GCI, there is a rapid, robust elevation of endogenous Aβ in LTED females after GCI. In STED females, we observed that GCI attenuates and E2 maintains A Disintegrin and Metalloprotease 10 （ADAM 10） expression in the hippocampal CA1, and concurrently, GCI increases and E2 decreases BACE1 levels in the same region. Intriguingly, however, we observed a loss of E2 regulation of ADAM 10, ADAM 17, and BACE 1 levels in the hippocampal CA I of LTED females, which provides mechanistic evidence for the enhanced post-ischemic Aβ load following LTED. We also observed loss of E2 regulation of tau hyperphosphorylation in LTED females subjected to GCI. Conclusion： Collectively, these studies partially explain the enhanced risk of dementia and mortality from neurological disorders seen in prematurely menopausal women and support timely initiation of E2 therapy to yield maximum neurological benefit.

大鼠脑缺血预处理的神经保护作用与调节核因子-KB和Hes1表达有关

目的通过钡0定大鼠脑缺血再灌注后海马核因子-KB（nuclear factor-KB，NF-KB）和HeslmRNA表达的变化来探讨脑缺血预处理的神经保护机制。方法健康雄性SD大鼠108只，随机分为脑缺血组、脑缺血预处理组和假手术组，再分为22h、48h、72h、7d、14d亚组。脑缺血预处理组大鼠在建立脑缺血再灌注损伤模型前3d通过右侧颈内动脉短暂性血流阻断10min实施缺血预处理。在脑缺血再灌注后各时问点进行神经功能评分、脑梗死体积测定并通过实时荧光定量聚合酶链反应测定海马NF-kB和HeslmRNA表达。结果脑缺血预处理组各时间点神经功能缺损评分和脑梗死体积百分比均显著低于脑缺血再灌注组（P均〈0．05）。各组NF-KB和HeslmRNA表达水平均随时间推移出现进行性降低，对同一时间点进行的比较显示，脑缺血预处理组和脑缺血再灌注组NF-KB和HeslmRNA表达水平均显著高于假手术组，但脑缺血预处理组NF-KBmRNA表达水平显著低于脑缺血再灌注组，而HeslmRNA表达水平显著高于脑缺血再灌注组（P均〈0．05）结论Hesl的上调和NF-KB的下调可能与脑缺血预处理的神经保护机制有关。

反复双侧颈总动脉闭塞小鼠海马Akt和糖原合成酶激酶-3β表达

目的探讨反复双侧颈总动脉闭塞所致血管性痴呆（vasculardementia，VaD）小鼠海马Akt和糖原合成酶激酶-3β（gtycogensynthasekinase-3β，GSK3β）蛋白表达。方法48只健康雄性C5781／6小鼠随机分为正常组、假手术组和模型组，每组16只。模型组采用反复3次间断阻断双侧颈总动脉建立小鼠VaD模型，假手术组只分离双侧颈总动脉但不阻断，正常组不接受任何处理。术后4周利用水迷宫实验和跳台实验观测各组小鼠行为学改变，采用HE染色观察海马组织病理学变化，采用蛋白质印迹法检测海马Akt、P．Akt（Ser473）、GSK3p、p-GSK3p（Set9）蛋白表达。结果水迷宫实验中，模型组学习阶段和记忆阶段游完全程时间延长（学习阶段：F=19．389，P〈0．05；记忆阶段：F=27．929，P〈0．05），错误次数增加（学习阶段：F=7．228，P〈0．05；记忆阶段：F=21．189，P〈0．05）；跳台实验中，模型组小鼠学习阶段反应时间延长（F=19．162，P〈0．05）、错误次数增加（F=6．562，P〈0．05），记忆阶段潜伏时间缩短（F=10．634，P〈0．05）、错误次数增加（F=12．890，P〈0．05）。同时，HE染色显示模型组海马CA1区神经元减少，神经胶质细胞增生；p-Akt（Ser473）（F=37．849，P〈0．05）和P—GSK3β（Set9）（F=67．725，P〈0．05）蛋白表达在术后4周较假手术组显著上调，而各组间Akt（F=1．004，P〉0．05）和GSK3β（F=0．329，P〉0．05）总蛋白表达无显著差异。结论反复双侧颈总动脉闭塞可造成小鼠学习记忆障碍，海马组织受损严重。磷酸化Akt和GSK3β表达可能参与了VaD的机制。

Duplicate preconditioning with sevoflurane in vitro improves neuroprotection in rat brain via activating the extracellular signal-regulated protein kinase

Objective Sevoflurane preconditioning has been demonstrated to reduce cerebral ischemia–reperfusion（IR） injury,but the underlying mechanisms have not been fully elucidated.Besides,different protocols would usually lead to different results.The objective of this study was to determine whether dual exposure to sevoflurane improves the effect of anesthetic preconditioning against oxygen and glucose deprivation（OGD）injury in vitro.Methods Rat hippocampal slices under normoxic conditions（95%O2/5%CO2）were pre-exposed to sevoflurane 1,2 and 3 minimum alveolar concentration （MAC）for 30 min,once or twice,with 15-min washout after each exposure.The slices were then subjected to 13-min OGD treatment（95%N2/5%CO2,glucose-free）,followed by 30-min reoxygenation.The population spikes（PSs）were recorded in the CA1 region of rat hippocampus.The percentage of PS amplitude at the end of 30-min reoxygenation to that before OGD treatment was calculated,since it could indicate the recovery degree of neuronal function.In addition,to assess the role of mitogen-activated protein kinases（MAPKs）in preconditioning,U0126,an inhibitor of extracellular signal–regulated protein kinase（MEK-ERK1/2,ERK1/2 MAPK）,and SB203580,an inhibitor of p38 MAPK,were separately added 10 min before sevoflurane exposure.Results Preconditioning once with sevoflurane 1,2,and 3 MAC increased the percentage of PS amplitude at the end of 30-min reoxygenation to that before OGD treatment,from（15.13±3.79）%（control）to（31.88±5.36）%, （44.00±5.01）%,and（49.50±6.25）%,respectively,and twice preconditioning with sevoflurane 1,2,and 3 MAC increased the percentage to（38.53±4.36）%,（50.74±7.05）%and（55.86±6.23）%,respectively.The effect of duplicate preconditioning with sevoflurane 3 MAC was blocked by U0126[（16.23±4.62）%].Conclusion Sevoflurane preconditioning can induce neuroprotection against OGD injury in vitro,and preconditioning twice enhances this effect.Besides,the activation of extracellular signal–regulated protein kinase（MEK-ERK1/2,ERK1/2 MAPK）may be involved in this process.

A selective reduction in the relative density of parvalbumin-immunoreactive neurons in the hippocampus in schizophrenia patients

Objectives To determine the relative densities of the GABAergic subpopulation defined by calcium-binding proteins and to further study the importance of changes in GABAergic interneurons on neuropathology in the hippocampus in schizophrenia cases. Methods The relative densities and neuronal body size of cells immunoreactive for the calcium-binding proteins parvalbumin and calretinin as well as the area size of the hippocampal sub-fields were determined from the hippocampal tissue sections taken from schizophrenic patients and well-matched control subjects (15 per group). Results No significant difference in the density of calretinin-immunoreactive neurons and the neuronal body size of calretinin-positive neurons was found between subject groups. Relative to normal controls, schizophrenic patients showed a significant and profound deficit in the relative densities of parvalbumin-immunoreactive neurons in all hippocampal sub-fields. These reductions were more apparent in male schizophrenic patients and were unrelated to antipsychotic drug treatment, age or duration of illness. Conclusion The findings provide further evidence to support a profound and selective abnormality of a sub-population of GABAergic neurons in the hippocampus in schizophrenia cases, and are consistent with the etiological hypothesis of the neurodevelopment of schizophrenia.

Effect of eye acupuncture on the expression of brainderived neurotrophic factor in hippocampus in rats with cerebral ischemia-reperfusion injury

Objective To observe the effects of eye acupuncture on expression of brain-derived neurotrophic factor （BDNF） in the hippocampus of rats after ischemia- reperfusion injury in order to study the mechanisms of eye acupuncture in improving ischemia-reperfusion injury. Methods SD rats were randomly divided into a normal group, a sham-operation group, a model group and an eye acupuncture group, with 8 rats in each. The cerebral ischemia-reperfusion injury model was established by thread occlusion method. Acupuncture at ＂liver＂, ＂upper-jiao＂, ＂lower-jiao＂, and ＂kidney＂ was performed for 20 min in the eye acupuncture group immediateness, 12 h and 23.5 h after the reperfusion. After 24 h of the reperfusion, the neurophysical behaviors were evaluated by Zea Longa neurophysical impairment score; the expression of ischemic hippocampus BDNF mRNA was measured by RT-PCR; the expression of ischemic hippocampus BDNF protein was detected by Western blot technique. Results After reperfusion 24 h, compared with the model group, the neurologic impairment score of the eye acupuncture group decreased significantly （P〈0.01）; the expressions of BDNF mRNA and protein in rat hippocampi after the eye acupuncture therapy were both obviously increased （P〈0.01）. Conclusion The eye acupuncture therapy is beneficial for neurofunctional rehabilitation by promoting the repair of the nerve cell which is induced by increasing hippocampus BDNF expression.

Anti-depression effects of electroacupuncture through up-regulating serum E_2 and BDNF and expression of BDNF in hippocampus in chronic depression rats

Objective：To investigate the effects of electroacupuncture （EA） at acupoints Baihui （GV 20）, Neiguan （PC 6） and Sanyinjiao （SP 6） on the levels of estradiol （E2） and brain-derived neurotrophic factor （BDNF） in serum, as well as the expression of BDNF in hippocampus in chronic depression rat models. Methods：Thirty female Wistar rats were randomly divided into three groups, including a normal control （NC） group, a model group and an EA group, 10 rats in each group. The depression model was established by using chronic unpredicted mild stress （CUMS）, such as cold-water swimming, tail clamping, electric shock to foot, etc., combined with individual caging for 21 d. Rats in the model group and EA group were randomly exposed to one of the 9 stressors each day and caged individually. After modeling, rats in the EA group were then treated with EA at Baihui （GV 20）, Neiguan （PC 6） and Sanyinjiao （SP 6） once daily for 14 d, and the model group was not treated with EA but bounded in the same way as the EA group. Serum E2 was measured by radioimmunoassay and BDNF was assessed by an enzyme-linked immunosorbent assay （ELISA） and the expression of BDNF in hippocampus was detected by using immunohistochemistry. Results：After the stress stimulation, compared with the NC group, the model group and EA group showed a significant reduction of sucrose preference rate （P〈0.01） and remarkable increase of forced-swimming immobility time （P〈0.01）. In addition, EA significantly reduced the depression-like behavior of rats in the EA group （P〈0.01）. The expressions of E2 and BDNF in serum as well as the expression of BDNF in hippocampus were remarkably lower in the model rats than those in the NC group （P〈0.01,P〈0.01,P〈0.05）. The expression of BDNF in rats’ serum and hippocampus in the EA group was significantly higher than that in the model group （P〈0.05）, while serum E2 increased but insignificantly （P〉0.05）. Conclusion：E2 and BDNF may contribute to the depression-like behaviors of the rats during CUMS period. EA may exert its anti-depression effects through promoting BDNF expression in serum and hippocampus.

Time window characteristics of cultured rat hippocampal neurons subjected to ischemia and reperfusion

Objective: To explore cell death and apoptosis in rat hippocampal neurons at different time points after ischemia, hypoxia and reperfusion injury and to elucidate time window characteristics in ischemia neuronal injury. Methods: Hippocampal neurons were obtained from rat embryo and were cultured in vitro. The ischemia and reperfusion of cultured rat hippocampal neurons were simulated by oxygen-glucose deprivation (OGD) and recovery. OGD at different time points ((0.25) h to (3.0) h) and then the same recovery (24 h) were prepared. Annexin (V-PI) staining and flow cytometry examined neuron death and apoptosis at different time after injury. Results: After OGD and recovery, both necrosis and apoptosis were observed. At different times after OGD, there were statistically significant differences in neuron necrosis rate (P<(0.05)), but not in apoptosis rate (P>(0.05)). At recovery, survival rate of hippocampal neurons further decreased while apoptosis rate increased. Furthermore, apoptosis rates of different time differed greatly (P<(0.05)). Apoptosis rate gradually increased with significant difference among those of different time points (P<(0.05)). However, 2 h after ischemia, apoptosis rate decreased markedly. Conclusions: Apoptosis is an important pathway of delayed neuron death. The therapeutic time window should be within 2 h after cerebral ischemia and hypoxia.

Effect of Transcutaneous Electrical Acupoint Stimulation on Rats with Chronic Exercise-induced Fatigue

Objective： To observe the effect of transcutaneous electrical acupoint stimulation （TEAS） on the rats with exercise-induced fatigue. Methods： Rat model of chromic exercise-induced fatigue was established with increasing load treadmill walking method. The TEAS therapy was operated immediately and 3 h after the exercise from the sixth week. Hippocampal morphology and hypothalamic morphology were observed with HE staining and the expressions of 5-hydroxytryptamine （5-HT） in hippocampus and hypothalamus were tested with immunohistochemical （IHC） staining after 2-week treatment. Results： TEAS released the damage of hippocampal morphology and hypothalamic morphology induced by exercise significantly and reduced the expression of 5-HT in hippocampus and hypothalamus. The difference between the therapy operated immediately and 3 h after exercise was not significant. Conclusion： TEAS could improve the fatigue recovery and athletic ability. The improvement of TEAS on the rats with exercise-induced fatigue was related with the decreased expression of central 5-HT and the reduction of damaged nerve cells.

Airborne fine particulate matter induces cognitive and emotional disorders in offspring mice exposed during pregnancy

Gestational exposure to PM_(2.5) is associated with adverse postnatal outcomes.PM_(2.5) can enter alveoli by using intratracheal instillation,even penetrate through lung cells into the blood circulation.Subsequently,they are transferred across the placenta and fetal blood brain barrier,causing the adverse birth outcomes of offspring.This study demonstrated that the gestational exposure resulted in cognitive and emotional disorders in female offspring although the offspring were not exposed to PM_(2.5).Placental metabolic pathways modulated fetal brain development and played a pivotal role for maternal-placentalfetal interactions in the fetal programming of adult behavioral and mental disorders.Samples of fetus,offspring hippocampus and placenta from the mice exposed to PM_(2.5) were investigated using a comprehensive approach including mass spectrometry-based lipidomics and three-dimensional imaging.The exposure induced the neuro-degeneration in hippocampus,impairment of placental cytoarchitecture,and reprogramming of lipidome,which might affect the modulation of maternal-fetal cross-talk and result in the behavior disorders of offspring.The variation of spatial distribution of lipids was profoundly affected in dorsal pallium and hippocampal formation regions of fetal brain,offspring hippocampus,as well as labyrinth and junctional zones of placenta.The abundance alteration of lipid markers associated with neurodegenerative diseases was validated in transgenic mouse model with Alzheimer’s disease and human cerebrospinal fluid from patients with Parkinson’s disease.The finding could help with the selection of more suitable heterogeneous-related substructures targeting PM_(2.5) exposure and the exploration of PM_(2.5)-induced toxicological effects on neurodegenerative diseases.

On brain activity mapping: Insights and lessons from Brain Decoding Project to map memory patterns in the hippocampus

The BRAIN project recently announced by the president Obama is the reflection of unrelenting human quest for cracking the brain code, the patterns of neuronal activity that define who we are and what we are. While the Brain Activity Mapping proposal has rightly emphasized on the need to develop new technologies for measuring every spike from every neuron, it might be helpful to consider both the theoretical and experimental aspects that would accelerate our search for the organizing principles of the brain code. Here we share several insights and lessons from the similar proposal, namely, Brain Decoding Project that we initiated since 2007. We provide a specific example in our initial mapping of real-time memory traces from one part of the memory circuit, namely, the CA1 region of the mouse hippocampus. We show how innovative behavioral tasks and appropriate mathematical analyses of large datasets can play equally, if not more, important roles in uncovering the specific-to-general feature-coding cell assembly mechanism by which episodic memory, semantic knowledge, and imagination are generated and organized. Our own experiences suggest that the bottleneck of the Brain Project is not only at merely developing additional new technologies, but also the lack of efficient avenues to disseminate cutting edge platforms and decoding expertise to neuroscience community. Therefore, we propose that in order to harness unique insights and extensive knowledge from various investigators working in diverse neuroscience subfields, ranging from perception and emotion to memory and social behaviors, the BRAIN project should create a set of International and National Brain Decoding Centers at which cutting-edge recording technologies and expertise on analyzing large datasets analyses can be made readily available to the entire community of neuroscientists who can apply and schedule to perform cutting-edge research.