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1.
BACKGROUND: In addition to neuroprotective genes, the targeted genes of hypoxia-inducible factor 1α (HIF-1α) include pro-apoptotic genes. However, the influence of HIF-1α on neuronal apoptosis in hypoxia-ischemia remains poorly understood. OBJECTIVE: To investigate the relationship between HIF-1α expression and neuronal apoptosis in hypoxia or hypoxia-ischemia brain injury and to determine the role of HIF-1α in regulating neuronal apoptosis. DESIGN, TIME AND SETTING: A randomized, controlled animal experiment was performed at the Laboratory of Children Neurology of Sichuan University between May 2006 and May 2007. MATERIALS: In situ cell death detected kit was provided by Roche, USA; rabbit anti-mouse HIF-1α polyclonal antibody was purchased from Santa Cruz Biotechnologies, USA; rabbit anti-mouse cleaved caspase-3 polyclonal antibody was purchased from Chemicon, USA. METHODS: A total of 36 Sprague Dawley rats aged 10 days were randomly assigned to 3 groups: sham-surgery, hypoxia, and hypoxia-ischemia, with 12 rats per group. The rats were treated at 3 time points: 4, 8, and 24 hours, with 4 rats per time point. In the hypoxia-ischemia group, the right common carotid artery was exposed and permanently ligated through a midline cervical incision. A 2.5-hour exposure to hypoxia (8% O2/92% N2) was used to induce hypoxia-ischemia injury. In the hypoxia group, rats were exposed to hypoxia without ligation of the common carotid artery. In the sham-surgery group, the common carotid artery was exposed without ligation or hypoxia. MAIN OUTCOME MEASURES: Histopathological changes, HIF-1α and activated caspase-3 protein expression, integrated optical density of positive cells, and apoptosis-positive cells. RESULTS: Hematoxylin and eosin staining showed that neuronal degeneration and edema was most prominent at 24 hours after hypoxia-ischemia. HIF-1α protein expression was significantly upregulated at 4 hours, peaked at 8 hours, and decreased at 24 hours after hypoxia or hypoxia-ischemia. HIF-1α protein expression was significant greater in the hypoxia and hypoxia-ischemia groups compared with the sham-surgery group (P 〈 0.01). Activated caspase-3 protein expression began to increase at 4 and 8 hours following hypoxia or hypoxia-ischemia and was significantly upregulated at 24 hours. Activated caspase-3 protein expression remained at low levels in the sham controls compared with the hypoxia and hypoxia-ischemia groups (P〈 0.01). TUNEL staining showed that the number of apoptotic cells significantly increased at 24 hours after hypoxia or hypoxia-ischemia. In addition, HIF-1α protein expression was greater in the hypoxia group compared with the hypoxia-ischemia group at the same time point (P 〈 0.05). However, activated caspase-3 expression and the number of TUNEL-positive cells were less in the hypoxia group compared with the hypoxia-ischemia group at the same time point (P〈 0.05). CONCLUSION: HIF-1α played a neuroprotective role following hypoxia-ischemia brain injury.  相似文献   

2.
BACKGROUND: Recent studies have suggested that mitochondrial ATP-sensitive K+ channel openers could reduce myocardium infarct size, and protect the function of the mitochondria. OBJECTIVE: To investigate the changes of cerebral infarction volume and the activity of marker enzymes in brain mitochondria of rats given the ATP-sensitive K+ channel opener, nicorandil, before focal cerebral ischemia/reperfusion (I/R). DESIGN, TIME AND SETTING: Randomized, controlled animal experiment, completed at the Brain Scientific Research Center of the Affiliated Hospital of Qingdao University from July to November 2007. MATERIALS: Sixty healthy male Wistar rats weighing 280-300 g. Nicorandil, 5-hydroxydecanoate (5-HD) and cytochrome C were purchased from Sigma in the USA. Standard malondialdehyde (MDA) and protein were purchased from Nanjing Jiancheng Biotechnology Institute. METHODS: Sixty rats were randomly divided into a sham operation group, a middle cerebral artery occlusion (MCAO) group, a nicorandil group and a nicorandil+5-HD group. MCAO for 2 hours was performed in the MCAO group, nicorandil group and nicorandil+5-HD group. A total of 5 mL saline were given to the MCAO group before MCAO. The nicorandil group was injected with the ATP-sensitive K+ channel opener nicorandil 10 mg/kg intraperitoneally 30 minutes before MCAO. The nicorandil+5-HD group was injected with 5-HD 10 mg/kg intravenously 15 minutes before the same treatment as the nicorandil group. MAIN OUTCOME MEASURES: Infarct volume by total brain slice calculation, activities of succinate dehydrogenase (SDH) and cytochrome oxidase (CO), and content of MDA were observed at 22 hours of reperfusion after 2 hours MCAO. RESULTS: Sixty rats were included in the final analysis, without any loss. (1) Infarct volume: compared with the MCAO group and nicorandil+5-HD group, the percentage of infarct volume was significantly decreased in the nicorandil group (P 〈 0.01). (2) The content of MDA, expression of  相似文献   

3.
BACKGROUND: Stellate ganglion block (SGB) plays a protective role on the brain, but the precise mechanism of action is not clear. OBJECTIVE: To simulate SGB by transection of the cervical sympathetic trunk (TCST) and to investigate the TCST effects on changes in cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury. DESIGN, TIME AND SETTING: A complete randomized control animal experiment was performed at the Institute of Neurological Diseases of Taihe Hospital, Yunyang Medical College from February to December 2005. MATERIALS: A total of 101 healthy Wistar rats, weighing 280-320 g, of both genders, aged 17-18 weeks, were used in this study. 2, 3, 5-triphenyltetrazolium chloride (TTC) was purchased from Changsha Hongyuan Biological Company. Superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) assay kits were provided by Nanjing Jiancheng Bioengineering Institute. METHODS: Rats were randomly divided into a TCST group, a model group and a sham operation group. Successful models were included in the final analysis, with at least 20 rats in each group. After TCST, rat models of focal cerebral ischemia/reperfusion injury were established in the TCST group by receiving middle cerebral artery occlusion (MCAO) by the intraluminal suture method for 2 hours, followed by 24 hours of reperfusion. Rat models of focal cerebral ischemia/reperfusion injury were made in the model group. Rats in the sham operation group underwent experimental procedures as for the model group, threading depth of 10 mm, and middle cerebral artery was not ligated. MAIN OUTCOME MEASURES: Brain tissue sections of ten rats from each group were used to measure cerebral infarct volume by TTC staining. Brain tissue homogenate of another ten rats from each group was used to detect SOD activities, MDA contents and NO levels. Rat neurological function was assessed by neurobehavioral measures. RESULTS: Cerebral infarct volume was bigger in the  相似文献   

4.
BACKGROUND: The stellate ganglion block (SGB) plays a protective role in focal cerebral ischemia/reperfusion injury. The human SGB can be simulated by transection of the cervical sympathetic trunk (TCST) in rats. OBJECTIVE: To observe the effects of TCST on inducible nitric oxide synthase (iNOS) levels and cerebral infarct volume in the hippocampus of rats with cerebral ischemia/reperfusion injury, and to analyze the mechanism of action. DESIGN, TIME AND SETTING: A completely randomized, controlled, neuropathological experiment was performed at the Institute of Neurological Disease, Taihe Hospital, Yunyang Medical College between March and September 2006. MATERIALS: A total of 93 Wistar rats, aged 1718 weeks, of either gender, were used for this study. 2, 3, 5-triphenyl tetrazolium chloride was purchased from Changsha Hongyuan Biological Reagent Company China. Rabbit iNOS antibody and goat anti-rabbit IgG antibody were the products of Wuhan Boster Biological Reagent Co., Ltd., China. METHODS: Ten rats were randomly selected for the sham-operated group. Cerebral ischemia/reperfusion injury was induced by middle cerebral artery occlusion (MCAO) using the suture method in the remaining rats. Forty successful rat models were randomly and equally divided into the following two groups: (1) TCST group: subsequent to TCST, MCAO was performed for 2 hours, followed by 24 hours reperfusion; (2) model group: rats underwent experimental procedures similar to the TCST group, with the exception of TCST. Rats in the sham-operated group were subjected to experimental procedures similar to the model group; however, the thread was only introduced to a depth of 10 mm. MAIN OUTCOME MEASURES: Following 24 hours of reperfusion, functional neurological deficits were scored. Brain tissue sections from ten rats of each group were used to measure cerebral infarct volume by TTC staining. Hippocampal tissue sections of an additional ten rats from each group were used to detect iNOS levels using the s  相似文献   

5.
BACKGROUND: Hypoxia-inducible factor 1 (HIF-1) can lead to the adaptative reaction of body for hypoxia and ischemia. HIF-1 plays an important role in the response of ischemia-hypoxia. At present, there has been no overall report on the significance for the expression of HIF-1 following experimental cerebral ischemia. OBJECTIVE: To observe the expression of HIF-1 after middle cerebral artery occlusion (MCAO) by immunohistochemical method. DESIGN: Completely randomly grouped controlled animal experiment. SETTING: Second Hospital, Xi'an Jiaotong University. MATERIALS: Thirty-six Sprague-Dawley healthy male rats, with body mass of 250–330 g, were used in this study. Thirty-six rats were randomized into 3 groups: pre-ischemia group, sham-operation group and control group, with 12 rats in each. METHODS: This study was carried out in the clinical laboratory, People's Hospital of Ningjin County of Shandong Province from March 2006 to January 2007. Rats in the pre-ischemia group were created into pre-ischemia models by two embolisms twice. Three days after ischemic preconditioning, middle cerebral artery (MCA) was occluded for 2 hours with the same method. After being perfused for 22 hours, the rats were euthanized. In the sham-operation group, rats were not given the treatment of pre-ischemia. In the first operation, only common carotid artery (CCA) and its crotch were exposed in the first operation, and MCA was not blocked by inserting embolism. At postoperative 3 days, rats were euthanized after being subjected to MCAO for 2 hours and reperfusion 22 hours by the same procedure as that in the pre-ischemia group. As for each rat in the control group, only CCA and its crotch were exposed, and no any other treatment was carried out on them. MAIN OUTCOME MEASURES: Brain tissue of each rat was performed immunohistochemical staining at reperfusion 22 hours after pre-ischemia, HIF-1 expression and brain infarct volume were detected. RESULTS: Thirty-six Sprague-Dawley rats were involved in the experiment. During the experiment, 8 rats dropped out, and another 8 rats were supplemented. The infarct volume of rats in the pre-ischemia group was significantly smaller than that in the sham-operation group (t =3.22, P < 0.01). HIF-1 expression was not found in the control group, but many HIF-1 positive cells were found in the other two groups. Absorbance in the pre-ischemia group was significantly higher than that in the sham-operation group (t =4.31, P < 0.01). CONCLUSION: Slight ischemia caused preconditioning can increase HIF-1 content, and it is one of protective mechanisms for nerve cells.  相似文献   

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8.
BACKGROUND: Inhibitory signals, i.e. neurite growth inhibitors (NGIs), presenting on central nervous system (CNS) myelin have been shown to play a crucial role in inhibiting lesioned axonal sprouting and leading to less functional recovery. Vaccines targeting NGIs may provide multifactorial protection against brain insults by overcoming the inhibitory effects of these NGIs and boosting the body's immune repair mechanisms. OBJECTIVE: To evaluate the effect of poststroke DNA immunization against NGIs on the rehabilitation for sensorimotor function of rat models of local cerebral ischemia. DESIGN: Completely randomized grouping design, and controlled experiment. SETTING: Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore. MATERIALS: Sixty adult male Sprague-Dawley rats ranging in age from 45 to 120 days and in weight from 180 to 250 grams were provided by Animal Center of Department of Anatomy, Faculty of Medicine, National University of Singapore. pcDNA3.1(+)-neurite growth inhibitors (pcDNA-NGIs) a gift was provided by Dr. Xiao from Department of Clinical Research, Singapore General Hospital, Singapore. METHODS: The experiment was carried out at Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore from August 2003 to April 2005. (1)The involved rats were randomized into 3 groups: pcDNA-NGIs group (group A), pcDNA3.1 (+) group (group B) and model group (group C), with 20 rats in each group. Left focal cerebral ischemia (FCI) was permanently induced through middle cerebral artery occlusion (MCAO) with the assistance of an operating microscope. Successful MCAO was determined by a 20% decrease to baseline in the ipsilateral cerebral blood flow. 100 μg of pcDNA-NGIs eluted in phosphate-buffered saline (PBS) was intramuscularly injected into the tibial muscle once a week after MCAO for 6 weeks in group A. As control, pcDNA3.1 (+) was also administrated in the same way in group B and nothing was administrated in group C. (2) The modified neurological severity score (mNSS), a composite of motor, sensory, reflex and balance tests, was used to test the sensorimotor deficit. The mNSS was graded on a scale of 0 - 18, i.e. normal score was 0, maximal deficit score was 18, and 1 point was warded for the inability to perform the tasks or the lack of a tested reflex. (3) The newly generated axons of corticorubral projection were traced by stereotaxic guided injection of 100 g/L biotinylated dextran amine. Rats were sacrificed two weeks after tracing, and cryostat coronal sections of midbrains (30μm) were reacted to BDA according to the manufacturer's instruction by the free-floating method. Images were captured on a DM RXA2 LEICA Microscope with a Spot Digital Camera system (Germany), and the numbers of labeled axons on the denervated side in four standard coronal sections including the red nucleus were manually quantified. MAIN OUTCOME MEASURES: (1) The number of newly generated axons of corticorubral projection. (2)The improvement in sensorimotor deficit. RESULTS: All the involved 60 rats entered the stage of final analysis. (1) The number of newly generated axons of corticorubral projection of rats: Only ipsilateral axons of CRP were noted with little evidence of fibers crossing to the contralateral red nucleus in rats of groups B and C. More BDA-positive fibers crossing the midline and terminating in the contralateral red nucleus in appropriate target areas mirroring the non-differentiated red nucleus were found in rats of group A. Quantitative analysis showed that BDA-labeled axons in the denervated side of rats in group A were more than those in group B (P 〈 0.05). (2) Improvement in sensorimotor deficit of rats: At 2 weeks after immunization, significant improvement in sensorimotor deficit was found in rats of group A. There were significant differences of improvement in sensorimotor deficit of rats between group A and group B or group C at 12 and 14 weeks after immunization (P 〈 0.05). CONCLUSION: (1) Poststroke DNA immunization against NGIs leads to increased sensorimotor recovery following FCI and compensatory newly growth of axons from corticorubral projection.  相似文献   

9.
Rhodioloside has been shown to protect cells from hypoxia injury,and bone marrow mesenchymal stem cells have a good efrect on tissue repair.To study the effects of rhodioloside and bone marrow mesenchymal stem cells on spinal cord injury,a rat model of spinal cord injury was established using the Infinite Horizons method.After establishing the model,the rats were randomly divided into five groups.Rats in the control group were intragastrically injected with phosphate buffered saline(PBS)(5μL).PBS was injected at 6 equidistant points around5 mm from the injury site and at a depth of 5 mm.Rats in the rhodioloside group were intragastrically injected with rhodioloside(5 g/kg)and intramuscularly injected with PBS.Rats in the mesenchymal stem cell(MSC)group were intramuscularly injected with PBS and intramuscularly with MSCs(8×10~6/mL in a 50-μL. cell suspension).Rats in the Ad-HIF-MSC group were intragastrically injected with PBS and intramuscularly injected with HIF-1 adenovirus-infected MSCs.Rats in the rhodioloside+Ad-HIF-MSC group were intramuscularly injected with MSCs infected with the HIF-1 adenovirus and intragastrically injected with rhodioloside.One week after treatment,exercise recovery was evaluated with a modified combined behavioral score scale.Hematoxylin-eosin staining and Pischingert's methylene blue staining were used to detect any histological or pathological changes in spinal cord tissue.Levels of adenovirus IX and Sry mRNA were detected by real-time quantitative polymerase chain reaction and used to determine the number of adenovirus and mesenchymal stem cells that were transfected into the spinal cord.Immunohistochemical staining was applied to detect HIF-1 protein levels in the spinal cord.The results showed that:(1)compared with the other groups,the rhodioloside+Ad-HIF-MSC group exhibited the highest combined behavioral score(P0.05),the most recovered tissue,and the greatest number of neurons,as indicated by Pischingert's methylene blue staining.(2)Compared with the PBS group,HIF-1 protein expression was greater in the rhodioloside group(P0.05).(3)Compared with the Ad-HIF-MSC group,Sry mRNA levels were higher in the rhodioloside+Ad-HIF-MSC group(P0.05).These results confirm that rhodioloside combined with bone marrow mesenchymal stem cells can promote the recovery of spinal cord injury and activate the HIF-1 pathway to promote the survival of bone marrow mesenchymal stem cells and repair damaged neurons within spinal cord tissue.This experiment was approved by the Animal Ethics Committee of Gansu University of Traditional Chinese Medicine,China(approval No.2015KYLL029)in June 2015.  相似文献   

10.
BACKGROUND: Numerous studies have shown that transient ischemic preconditioning induces cerebral ischemic tolerance. However, the underlying mechanisms of endogenous protection following ischemic preconditioning remain unclear. OBJECTIVE: To dynamically measure erythropoietin and hypoxia-inducible factor-1α (HIF-1α) mRNA and protein expression at various times following preconditioning, and to investigate effects of erythropoietin and HIF-1α on cerebral ischemic tolerance in a model of focal ischemia/reperfusion established using the twice suture method. DESIGN, TIME AND SETTING: The randomized, controlled study was performed at the Institute of Anatomy, Medical College, Qingdao University, China from March 2006 to March 2007. MATERIALS: Rabbit anti-rat HIF-1α monoclonal antibody and biotinylated goat anti-rabbit IgG (Boster, China), rabbit anti-rat erythropoietin monoclonal antibody (Santa Cruz Biotechnology, USA), and one-step RT-PCR kit (Qiagen, Germany) were used in this study. METHODS: A total of 99 healthy, male, Wistar rats were randomly assigned to three groups: sham surgery (n = 9), non-ischemic preconditioning (n = 45), and ischemic preconditioning (n = 45). In the ischemic preconditioning group, rat models of pre-ischemia-reperfusion-ischemia-reperfusion were established by occluding the left middle cerebral artery using the twice suture method. In the non-ischemic preconditioning group, pre-ischemia was replaced by sham surgery. Subsequently, the ischemic preconditioning and non-ischemic preconditioning groups were equally divided into five subgroups according to time of first reperfusion, including 1-, 3-, 7-, 14-, and 21-day subgroups. The sham surgery group received the sham surgery twice. MAIN OUTCOME MEASURES: HIF-la and erythropoietin protein expression was measured in the cerebral cortex, corpus striatum, and hippocampus of the ischemic hemisphere. HIF-1α and erythropoietin mRNA expression were determined in the frontal and parietal cortex of the ischemic hemisphere. RESULTS: (1) Intergroup comparison: compared with the non-ischemic preconditioning group, HIF-1α protein expression significantly increased in the rat cerebral cortex, corpus striatum, and hippocampus in the ischemic hemisphere at 1,3, and 7 days following reperfusion in the ischemic preconditioning group (P 〈 0.05 or P 〈 0.01). Erythropoietin protein expression significantly increased in the cerebral cortex, corpus striatum, and hippocampus, as well as HIF-1α and erythropoietin mRNA expression in the frontal and parietal cortex in the ischemic hemisphere, at 3 and 7 days following reperfusion in the ischemic preconditioning group (P 〈 0.05). (2) Temporal expression: HIF-1α protein expression in the rat cerebral cortex, corpus striatum, and hippocampus, as well as HIF-la mRNA expression in the frontal and parietal cortex, in the ischemic hemisphere increased at 3 days, and gradually decreased from 7 days following reperfusion in the ischemic preconditioning group. Temporal erythropoietin protein and mRNA expression was consistent with HIF-1α protein expression. (3) Correlation: erythropoietin mRNA expression positively correlated with HIF-1α mRNA expression (r= 0.737, P 〈 0.01). CONCLUSION: Ischemic preconditioning induced cerebral ischemic tolerance. Pre-ischemiainduced increase in endogenous HIF-1αexpression, as well as its target gene erythropoietin, participated in the formation of cerebral ischemic tolerance.  相似文献   

11.
BACKGROUND: Certain components of tetramethylpyrazine, a traditional Chinese medicine, exhibit protective effects against brain injury. OBJECTIVE: To investigate the effects of different Naoxintong doses on expression of nuclear factor-kappa B ( kB), interleukin-6, tumor necrosis factor-α, and complement 3 in rats following focal cerebral ischemia. DESIGN, TIME AND SETTING: The randomized experiment was performed at the Laboratory of Neurology, Second Hospital of Hebei Medical University from June 2004 to June 2006. MATERIALS: A total of 150 adult, healthy, male, Sprague Dawley rats, weighing 280-320g, were selected. Naoxintong powder (mainly comprising szechwan lovage rhizome, milkvetch root, danshen root, and radix angelicae sinensis) was obtained from Buchang Pharmacy Co., Ltd. in Xianyang City of Shanxi Province of China, lot number 040608. METHODS: The rats were randomly assigned into sham operation, saline, high-dose Naoxintong, moderate-dose Naoxintong, and low-dose Naoxintong groups, with 30 rats in each group. Rat models of middle cerebral artery occlusion were established using the suture method, with the exception of the sham operation group. Rats in the high-dose, moderate-dose and low-dose Naoxintong groups received 4, 2, and 1 g/kg Naoxintong respectively, by gavage. Rats in the saline group were treated with 1 mL saline by gavage All rats were administered by gavage at 5 and 23 hours following surgery, and subsequently, once per day. MAIN OUTCOME MEASURES: At 6, 24, 48, 72 hours, and 7 days following model establishment, brain water content was measured. Histopathological changes in brain tissues were detected using hematoxylin-eosin staining. Expression of nuclear factor- kB, interleukin-6, tumor necrosis factor- α, and complement 3 was examined by immunohistochemistry. RESULTS: A total of 150 rats were included in the final analysis with no loss. Brain water content was significantly increased in the ischemic hemisphere of rats from the saline, as well as the high-dose, mo  相似文献   

12.
BACKGROUND:It has been reported that Ganoderma lucidum spore powder, a very well known Chinese traditional medicine, can affect immunoregulation, free radical scavenging, and anti-hypoxia responses. OBJECTIVE: To investigate the effect of Ganoderma lucidum spore powder on expression of insulin-like growth factor-1 (IGF-1), nuclear factor-κB (NF-κB) and neuronal apoptosis in rats with pentylenetetrazol (PTZ)-induced epilepsy. DESIGN, TIME AND SETTING: A cellular and molecular biology experiment with randomized controlled study design was performed at the Central Laboratory of Basic Medical College of Jiamusi University from June to August 2005. MATERIALS: Thirty healthy, adult, male, Wistar rats were selected and randomly divided into 3 groups (10 rats per group): control, epilepsy model, and Ganoderma lucidum spore powder. A sub-eclampsia PTZ dose (35 mg/kg) was intraperitoneally injected to induce epilepsy in the latter two groups. Wild Ganoderma lucidum spore powder (30 g/L) was provided by the wild Ganoderma lucidum plant nursery at Jiamusi, China. Immunohistochemical detection and terminal deoxynucleotidyl transferase-mediate dUTP nick end-labeling (TUNEL) kits were purchased from Wuhan Boster Biological Technology Co., Ltd., China. METHODS: Ganoderma lucidum spore powder was intragastrically administered at a dose of 10.0 mL/kg, once a day for 28 days. In the epilepsy and control groups, an equivalent volume of normal saline was intragastrically administered. MAIN OUTCOME MEASURES: Immunoreactivity for IGF-1 and NF-κB/P65 were detected by immunohistochemical staining. Neuronal apoptosis was detected using TUNEL methods. RESULTS: The hippocampus and cerebral cortex of rats with PTZ-induced epilepsy exhibited a higher number of apoptotic cells at high magnification (×400), compared with the control group. Expression of IGF-1 and NF-κB were higher in the epilepsy group, compared with the control group (P 〈 0.01). In Ganoderma lucidum spore-treated rats,  相似文献   

13.
BACKGROUND: α-asarone and acrous gramineus have been shown to play a necessary function in enhancing the reactivity and convulsant threshold to electric stimulation of immature rats. They have also been shown to effectively suppress epileptic seizures induced by pentylenetetrazol in young rats. However, the mechanisms for these roles have been still unclear. OBJECTIVE: To observe the effects in immature rats of acrous gramineus and α -asarone on apoptosis of hippocampal neurons after epileptic seizure at the protein level, and to analyze the mechanism for these effects. DESIGN: A randomized controlled animal experiment. SETTINGS: Department of Pediatrics, First Hospital of Jilin University; Department of Histology and Embryology, Norman Bethune Medical School of Jilin University; Department of Internal Medicine, Children's Hospital of Changchun City; Department of Neurology, First Clinical Hospital affiliated to Harbin Medical University. MATERIALS: Fifty 3-week old Wistar rats, 34-40 g, irrespective of gender, were provided by Gaoxin Research Center of Medical Animal Experiment, Changchun. The animals were treated according to the animal ethical standards. The following chemicals were used for this study: acrous gramineus powders or infusion (Batch No, 0307113, Tianjiang Medicine Company Limited, Jiangyin), α-asarone tablets (Batch No. 030219, Tianwei Pharmaceutical Factory, Shenyang), and phenobarbital sodium tablets (Batch No. 020608, Xinya Medicine Company Limited, Shanghai). The animals were divided into five groups randomly. First, ten rats were chosen as the normal controls. The remaining rats were treated with i.p. injections of pentylenetetrazol to stimulate an epileptic model. METHODS: The experiments were performed at the Neurological Laboratory of the First Hospital of Jilin University between October and December 2004. The rats were treated with i.p. injections of pentylenetetrazol (60 mg/kg) to establish an epileptic model. According to Racine' s standard, animal  相似文献   

14.
BACKGROUND: It has been shown that interleukin-1β(IL-1β) can induce fever by activating vascular endothelial cells and macrophages of the supraoptic crest to generate prostaglandin E2, which binds with receptors of the thermo-sensitive hypothalamic neurons. Lonicera japonica is one of the medicinal plants used widely in Asia for its antipyretic properties. However, these mechanisms have not yet been intensively studied.
OBJECTIVE: To investigate the antipyretic effect and mechanisms of Lonicera japonica on IL-1β- induced febrile New Zealand rabbits by observing expression changes of E-type prostaglandin receptor-3 (EP3) mRNA in the preoptic anterior hypothalamus (POAH). DESIGN: A randomized controlled study.
SETTING: Electrophysiological Laboratory at the Department of Pathophysiology, Medical College of Jinan University; Department of Orthopaedics, First Hospital Affiliated to Medical College of Jinan University.
MATERIALS: The experiment was performed from April to December 2005, using a total of 32 New Zealand white rabbits of both sexes, weighing 1.5 2.0 kg. All the animal experiments were performed according to the internationally accepted ethical guidelines. Lonicera japonica injection was purchased from Huanghe pharmaceutical factory of Xi'an, China. IL-1βwas purchased from Sigma, USA.
METHODS: A total of 32 rabbits were divided randomly into four groups: ① Normal saline (NS) control group;② Lonicerajaponica treatment group; ③ IL-1βtreatment group; and ④Lonicerajaponica plus IL-1βtreatment group. In the first 3 groups, the rabbits were given separate intravenous (i.v.) injections of l mL NS, l mL Lonicera japonica, and 100 ng IL-l β (dissolved in 0.9% NS without pyrogen). In the Lonicerajaponica plus IL-1βgroup each rabbit was given i.v. injections of l mL NS and, 30 minutes later, 100 ng IL-1 β. MAIN OUTCOME MEASURES: Colonic temperature of each rabbit was measured at 0, 10, 20, 30, 40, 50, 60, and 70 minutes after injection and the maxim  相似文献   

15.
BACKGROUND: Preparation of Ginkgo leaf has been widely used to improve cognitive deficits and dementia, in particular in Alzheirner's disease patients. However, the precise mechanism of action of Ginkgo leaf remains unclear. OBJECTIVE: To explore the effect of Ginkgo Biloba extract (Egb761), Ginaton, on β -secretase expression in rat hippocampal neuronal cultures following chronic hypoxic and hypoglycemic conditions. DESIGN, TIME AND SETTNG: Completely by randomized, grouping study. The experiment was performed at the Laboratory of Molecular Imaging, Southeast University between August 2006 and August 2007. MATERIALS: A total of 128 Wistar rats aged 24 hours were selected, and hippocampal neurons were harvested for primary cultures. METHODS: On day 7, primary hippocampal neuronal cultures were treated with Egb761 (0, 25, 50, 100, 150, and 200μg/mL) under hypoxic/hypoglycemic or hypoglycemic culture conditions for 12, 24, and 36 hours, respectively. Hippocampal neurons cultured in primary culture medium served as control. MAIN OUTCOME MEASURES: Cell viability was assayed using 3-(4,5-Dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT); fluorescence detection of β -secretase activity was performed; Western Blot was used to measure β -secretase expression. RESULTS: Cell viability under hypoxic/hypoglycemic or hypoglycemic culture conditions was significantly less than control cells (P 〈 0.05). Under hypoxic/hypoglycemic or hypoglycemic culture conditions, treatment with 25 μg/mL Egb761 did not alter cell viability. However, 〉 25 μg/mL Egb761 induced greater cell viability (P 〈 0.05). No differences were observed between hypoxic/hypoglycemic or hypoglycemic cells (P 〉 0.05). α -secretase activity was increased after 12 hours in hypoxic/hypoglycemic culture (P 〈 0.01). There were no significant differences between the 12-, 24-, or 36-hour Egb761 groups and the hypoxic/hypoglycemic groups (P 〉 0.05). β -secretase activity was greater after  相似文献   

16.
Extrasynaptic GABAA receptors (GABAARs)-mediated tonic inhibition is reported to involve in the patho- genesis of epilepsy. In this study, we used cyclo- thiazide (CTZ)-induced in vitro brain slice seizure model to explore the effect of selective activation of extrasynaptic GABAARS by 4,5,6,7-tetra- hydroisoxazolo[5,4-c] pyridine-3-ol (THIP) on the CTZ-induced epileptiform activity in hippocampal neurons. Perfusion with CTZ dose-dependently induced multiple epileptiform peaks of evoked population spikes (PSs)in CA1 pyramidal neurons, and treatment with THIP (5 μmol/L) significantly reduced the multiple PS peaks induced by CTZ stimulation. Western blot showed that the 6-subunit of the GABAAR, an extrasynaptic specific GABAAR subunit, was also significantly down-regulated in the cell membrane 2 h after CTZ treatment. Our results suggest that the CTZ-induced epileptiform activity in hippocampal CA1 neurons is suppressed by the activation of extrasynaptic GABAARs, and further support the hypothesis that tonic inhibition mediated by extrasynaptic GABAARs plays a prominent role in seizure generation.  相似文献   

17.
早年创伤是一个全球普遍存在的问题,严重影响儿童、青少年的大脑发育,继而导致认知功能、人格水平、社会行为的改变。早年创伤主要是父母、监护人或其他年长者对孩子施加躯体虐待、躯体忽视、情感虐待、情感忽视或性虐待。美国一项调查显示:儿童虐待事件的发生率高达1.2%[1]。早年创伤影响认知功能的多个领域,包括学习/工作记忆、视觉空间能力、执行功能、言语智能、复杂推理搜决策、学业表现等比]。创伤造成的认知功能改变是目前国内外神经科学和精神医学领域研究的热点,但其发病机制仍不明确,鉴于早年创伤与认知功能的关系问题,现就早年创伤对大脑发育、神经认知的影响加以综述。  相似文献   

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Objective To compare the cognitive effects of guqin (the oldest Chinese instrument) music and piano music. Methods Behavioral and event-related potential (ERP) data in a standard two-stimulus auditory oddball task were recorded and analyzed. Results This study replicated the previous results of culture-familiar music effect on Chinese subjects: the greater P300 amplitude in frontal areas in a culture-familiar music environment. At the same time, the difference between guqin music and piano music was observed in NI and later positive complex (LPC: including P300 and P500): a relatively higher participation of right anterior-temporal areas in Chinese subjects. Conclusion The results suggest that the special features of ERP responses to guqin music are the outcome of Chinese tonal language environments given the similarity between Guqin's tones and Mandarin lexical tones.  相似文献   

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Neuroimaging of cerebral glucose metabolism and blood flow is ideally suited to assay widely-distributed brain circuits as a result of local molecular events and behavioral modulation in the central nervous system. With the progress in novel analytical methodology, this endeavor has succeeded in unraveling the mechanisms underlying a wide spectrum of neurodegenerative diseases. In particular, statistical brain mapping studies have made significant strides in describing the pathophysiology of Parkinson's disease (PD) and related disorders by providing signature biomarkers to determine the systemic abnormalities in brain function and evaluate disease progression, therapeutic responses, and clinical correlates in patients. In this article, we review the relevant clinical applications in patients in relation to healthy volunteers with a focus on the generation of unique spatial covariance patterns associated with the motor and cognitive symptoms underlying PD. These characteristic biomarkers can be potentially used not only to improve patient recruitment but also to predict outcomes in clinical trials.  相似文献   

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