Cromakalin pretreatment affects mitochondrial structure and function in a rat model of ischemia/reperfusion injury☆

BACKGROUND：Mitochondrial structural changes and energy dysmetabolism frequently occur subsequent to cerebral ischemia.Adenosine triphosphate（ATP）-sensitive potassium channel openers exhibit protective effects on cerebral ischemia/reperfusion injury.OBJECTIVE：To validate the effects of cromakalin on mitochondrial structure and function in ischemic penumbra brain tissue in a rat model of middle cerebral artery occlusion（MCAO）.DESIGN,TIME AND SETTING：The present single-factor analysis of variance,randomized,controlled,animal experiment was performed at the Institute of Brain Science,Affiliated Hospital of Qingdao University Medical College between October 2007 and March 2008.MATERIALS：Forty male,Wistar rats were randomly divided into four groups,with 10 rats per group：sham-operated,MCAO,MCAO＋ATP-sensitive potassium channel opener（cromakalin）,and MCAO＋cromakalin＋ATP-sensitive potassium channel blocking agent（glibenclamide）.METHODS：Focal cerebral ischemia/reperfusion injury was induced by MCAO in all groups except the sham-operated group.The MCAO cromakalin group was administered 10 mg/kg cromakalin（i.p.） prior to MCAO induction.The MCAO＋cromakalin＋glibenclamide group received an injection of 10 mg/kg cromakalin（i.v.）,and subsequently an injection of 10 mg/kg cromakalin（i.p.） prior to MCAO induction.MAIN OUTCOME MEASURES：At 24 hours after cerebral ischemia/reperfusion injury,cellular apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate（dUTP） nick-end labeling technique.Cytochrome C expression was measured by immunohistochemistry.In addition,mitochondrial swelling,membrane fluidity,membrane phospholipid and malonaldehyde（MDA） contents,as well as Na^＋-K^＋-ATPase,Ca^2 ＋-ATPase,and superoxide dismutase（SOD） activities were determined.RESULTS：Compared with the sham-operated group,the three ischemia groups exhibited significantly elevated mitochondrial MDA content,reduced membrane phospholipid and ATP conten     

Effects of transection of cervical sympathetic trunk on cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury*★

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     

Cervical sympathetic trunk transection affects inducible nitric oxide synthase expression in rat hippocampus following focal cerebral ischemia/reperfusion injury

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     

Effects Of ATP Sensitive potassium channel opener on the mRNA and pro- tein expressions of caspase-12 after cerebral ischemia-reperfusion in rats

Objective To investigate effects of K_ATP opener on the expressions of caspase-12 mRNA and protein, and to explore the role of endoplasmic reticulum （ER） stress pathway in the mechanism of K_ATP opener protecting against neuronal apoptosis after cerebral ischemia-reperfusion. Methods Two hundred rats were randomly divided into four groups： sham operation group, ischemia-reperfusion group, K_ATP opener group, and K_ATP blocker group. The middle cerebral artery occlusion （MCAO） model was established by intraluminal suture occlusion method; neuronal apoptosis was detected by TUNEL staining. The mRNA and protein expressions of caspase-12 were detected by semi-quantitative RT-PCR and immunohisto-chemical staining, respectively. Results In ischemia-reperfusion group, K_ATP opener group and K_ATP blocker group, the number of apoptotic cells and the mRNA and protein expressions of caspase-12 gradually increased following cerebral reperfusion, and reached the peak at 24 h. In K_ATP opener group, The number of apoptotic cells was significantly less than that in ischemia-reperfusion group and K_ATP blocker group at 12 h, 24 h, 48 h and 72 h （P 〈 0.05 or P 〈 0.01）; while the mRNA and protein levels of caspase-12 were significantly less than those in ischemia-reperfusion group and K_ATP blocker group at all times （P 〈 0.05 or P〈0.01）. There were no differences between the ischemia-reperfusion group and K_ATP blocker group at each time （P〉 0.05）. Conclusion K_ATP opener may protect neurons from apoptosis following the cerebral ischemia-reperfusion by inhibiting ER stress pathway.     

Neuroprotective effect of high-dose hyperbaric oxygenation on rats with acute cerebral infarction in super-early stage

BACKGROUND: Previously, only single short-time low-dose hyperbaric oxygenation (HBO) protocol was administrated to treat acute ischemic stroke in early stage and the conflicting results were obtained. There are few studies to report the outcome of administering long-time (can cover all the natural pathologic progression period) high-dose HBO to treat the disease. OBJECTIVE: To evaluate the therapeutic effect between two kinds of high-dose hyperbaric oxygenation on super-early stage of acute permanent middle cerebral artery occlusion (MCAO) in rats. DESIGN: A randomized controlled experimental study. SETTING: Beijing Tiantan Hospital, Capital Medical University; Beijing Research Institute of Neurosurgery. MATERIALS: Seventy-four male SD rats, aged 2.5 months old, weighing （280±20）g, were provided by the Animal Institute, Chinese Academy of Medical Sciences. Hyperbaric oxygenation device was hyperbaric air cabin in which there was a self-made pure oxygen animal experimental cabin (made in China). METHODS: This experiment was carried out in the municipal laboratory of Beijing Tiantan Hospital affiliated to Capital Medical University and Beijing Research Institute of Neurosurgery. ① Experimental intervention: All the rats were developed into models of permanent MCAO by suture embolism. Then, they were randomly divided into two HBO groups (9 hours and 18 hours) and control group, with 24 rats in each as well as 3-hour ultrastructure control group, with 2 rats. After being modeled for 3 hours, rats in the two HBO groups stayed in the hyperbaric cabin for 9 hours and 18 hours, separately. Rats in the 9-hour HBO group inhaled pure oxygen at hours 1, 3, 5, 7 and 9, and hyperbaric air at hours 2, 4, 6 and 8. Rats in the 18-hour HBO group inhaled pure oxygen at hours 1, 3, 5, 7, 9, 11, 13, 15 and 17, and hyperbaric air at hours 2, 4, 6, 8, 10 12, 14, 16 and 18. After being created into models, rats in the control group and 3-hour ultrastructure control group breathed room air. ② Experimental evaluation: Neurologic functions of rat models in the 9-hour and 18-hour HBO groups as well as control group were scored by Bederson and Garica two neurological grading systems at hours 14 and 28 and on day 5; Infarct volume of rat models in the two HBO groups and control group was measured at hour 24 and on day 5 with NIH image processing software Image J; The pathological changes of brain tissue in the brain infarct region and its opposite region of rat models in the two HBO groups and 3-hour ultrastructure control group were observed with a Philips EM 208S transmission electron microscope. MAIN OUTCOME MEASURES: ① Neurobehavioral outcome. ② Rat brain infarct volume. ③ Ultrastructure of brain tissue in the ischemic penumbra of infarct models at the different time points RESULTS: ① Neurobehavioral outcome: After treatment, Garica score in the 9-hour and 18-hour HBO groups was significantly higher than that in the control group (P < 0.01). Bederson score on day 5 after modeling in the 9-hour and 18-hour HBO groups was significantly lower than that in the control group (P < 0.01). ② Cerebral infarct volume: Cerebral infarct volume in the 9-hour and 18-hour HBO groups was significantly smaller than that in the control group at hour 24 and on day 5 after modeling (P < 0.01). In the 18-hour HBO group, infarct volume on day 5 after modeling was significantly larger than that at hour 24 after modeling (P < 0.05). ③In the 3-hour ultrastructure control group, astrocyte edema and neuron damage around the capillary in the infarct cerebral tissue significantly relieved in the rats which were subjected to HBO. CONCLUSION: High dose of HBO is highly efficient in reducing infarct volume and improving neurobehavioral outcome of rats with acute cerebral infarction, and also has an important role in inhibiting the pathological progression of ischemic brain tissue after cerebral infarction.     

Effect of pre-ischemia on hypoxia-inducible factor expression in the brain tissue of rats with cerebral ischemia/reperfusion injury

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.     

七氟醚单次给药预处理缺血再灌注大鼠脑蛋白激酶Cε的转位激活及其延迟性保护作用

BACKGROUND： Brief exposure to the anesthetic sevoflurane results in delayed neuroprotection, However, few studies have addressed delayed neuroprotection after preconditioning with a single administration of sevoflurane. OBJECTIVE： To explore the relationship between a single preconditioning administration of sevoflurane and reactive oxygen species production and protein kinase C-epsilon （PKC-ε ） translocation. DESIGN, TIME, AND SETTING： The randomized, controlled, animal experiment was conducted at the Central Laboratory, Xiangya Hospital, Central South University, China from November 2007 to April 2008. MATERIALS： A total of 120 healthy, male, Sprague Dawley rats were equally and randomly assigned into five groups： sham operation, ischemia/reperfusion, sevoflurane, 2-mercaptopropionylglycine （2-MPG, a selective reactive oxygen species scavenger） ＋ sevoflurane （MPG ＋ sevoflurane）, and MPG. Sevoflurane （Baxter, USA） and MPG （Sigma, USA） were used in this study. METHODS： Intervention consisted of three procedures. （1） MPG injection： a selective reactive oxygen species scavenger, MPG （20 mg/kg）, was infused into the rat caudal vein in the MPG and MPG ＋ sevoflurane groups. （2） Sevoflurane preconditioning： 30 minutes following MPG injection, rats in the sevoflurane and MPG ＋ sevoflurane groups breathed a mixed gas of 2.4% sevoflurane and 97.6% oxygen for 60 minutes. Rats in the sham operation, ischemia/reperfusion, and MPG groups breathed 100% pure oxygen for 60 minutes. （3） IschemiaJreperfusion： 24 hours after sevoflurane or pure oxygen preconditioning, middle cerebral artery occlusion models were established in the ischemia/reperfusion, sevoflurane, MPG ＋ sevoflurane, and MPG groups. Following 2 hours ischemia/6 hours and 24 hours reperfusion, the carotid artery was separated, but the middle cerebral artery was not occluded, in the sham operation group. MAIN OUTCOME MEASURES： In the ischemic hemisphere, PKC-ε translocation in the rat parietal cortex was measured by Western blot analysis. Infarct volume was calculated using the TTC assay. Neurological deficits were evaluated in rats using a scoring system of 8 points. RESULTS： After 6 hours reperfusion, the ratio of PKC-ε in membrane/（cytosol ＋ membrane） was significantly less in the sham operation group than in the ischemia/reperfusion, sevoflurane, MPG ＋ sevoflurane）, and MPG groups （P 〈 0.05）. The ratio of PKC-ε in membrane/（cytosol ＋ membrane） was significantly greater in the sevoflurane group than in the sham operation, ischemia/reperfusion, MPG ＋ sevoflurane, and MPG groups （P 〈 0.05）. No significant differences were observed in the ischemiaJreperfusJon, M PG ＋ sevoflurane, and MPG groups （P 〉 0.05）. Following 24 hours reperfusion, the ratio of PKC-ε in membrane/（cytosol ＋ membrane） was significantly less in the sham operation group than in the ischemia/reperfusion, sevoflurane, MPG ＋ sevoflurane, and MPG groups （P 〈 0.05）. No significant differences were detected in the ischemia/reperfusion, sevoflurane, MPG ＋ sevoflurane, and MPG groups （P 〉 0.05）. Compared with the ischemia/reperfusion, MPG ＋ sevoflurane, and MPG groups, infarct volume was significantly smaller, and neurological deficits were significantly improved, in the sevoflurane group （P 〈 0.05）. No significant differences in infarct volume and neurological deficits were observed among the ischemia/reperfusion, MPG ＋ sevoflurane, and MPG groups （P 〉 0.05）. Infarcts or neurological deficits were not detected in the sham operation group. CONCLUSION： A single preconditioning administration of sevoflurane reduced infarct volumes and improved neurological deficits in ischemic rats. Delayed neuroprotection may be mediated by reactive oxygen species and correlated to PKC- ε activation.     

Effects of Rubus parvifolius L. on neuronal apoptosis and expression of apoptosis-related proteins in a rat model of focal cerebral ischemic-reperfusion injury*★

BACKGROUND： Studies have shown that the Rubus parvifolius L. （RP） plant extract exhibits protective effects on cerebral ischemia. This effect is reflected in altered ischemic neuronal apoptosis and associated protein expression.
OBJECTIVE： To explore the neuroprotective mechanism of RP after cerebral ischemia injury.
DESIGN, TIME AND SETTING： Randomized control experiment of cellular, molecular, and protein levels. The experiment was completed at Chongqing Medical University at the School of Pharmacy Laboratories and Basic Medical Institute from October 2005 to January 2006.
MATERIALS： Twenty-four adult, male, Wistar rats, weighing （28 ± 20） g. RP extract, which was a product of ethanol extraction, was provided by the Laboratory of Pharmaceutical Analysis, Chongqing Medical University. RP was dissolved in distilled water to a concentration of 10 mg/mL. All rats were randomly assigned into four groups： 5 g/kg RP, 10 g/kg RP, model, and sham-surgery, with 6 rats in each group.
METHODS： In the 5 and 10 g/kg RP groups, as well as the model group, the middle cerebral artery was occluded （MCAO） for 60 minutes, resulting in focal cerebral ischemia, followed by reperfusion for 24 hours. Rats in the 5 and 10 g/kg RP groups received 5 and 10 g/kg RP, respectively. The RP treatment group received RP intragastrically （once a day） for 3 days. One hour after the last dose, rats were subjected to MCAO. The same surgical procedure was performed in the sham-surgery group, except the suture was introduced into the external carotid artery, but not advanced. Rats in the model group were subjected to MCAO. The sham-surgery and model groups received intragastrically administered normal saline once per day for 3 days. One hour after the last dose, the rats were subjected to surgery.
MAIN OUTCOME MEASURES： TUNEL labeling and immunohistochemical methods were used to investigate changes in neuronal apoptosis and expression of the apoptosis-related proteins, Bax and Bcl-2, on the ischemic hemisphere     

Effect of restraint stress on depression-like behaviors in rats after transient focal cerebral ischemic injury

BACKGROUND: Restraint stress is a typical psychophysiological stressor. Simulating the early passion and difficulty in walking of patients after attack of stroke meets onset features. OBJECTIVE: To evaluate the effect of restraint stress on depression-like behaviors in rats after transient focal cerebral ischemic injury, and to investigate the feasibility for its being as modeling method of depression model after stroke. DESIGN: A randomized controlled animal experiment. SETTING: Department of Clinical Medicine, Faculty of Aerospace Medicine of the Fourth Military Medical University of Chinese PLA. MATERIALS: Forty-eight male Sprague-Dawley rats, weighing 240–270 g, provided by the Experimental Animal Center of the Fourth Military Medical University of Chinese PLA were used in the current study. METHODS: The experiments were carried out in the Faculty of Aerospace Medicine of the Fourth Military Medical University of Chinese PLA between August 2005 and August 2006. ①Experiment intervention: The rats were randomized into middle cerebral artery occlusion-reperfusion (MCAO) +stress group, simple MCAO group, sham-operation + stress group and simple sham-operation group, with 12 rats in each group. Rats in the first two groups were developed into cerebral ischemia/reperfusion models by suture-occluded method. Rats in the MCAO+stress group were modeled and restraint stress scheme was performed. At week 5 after modeling, the rats were placed in self-made restraining tubes, 2 hours/time, once a day, for 2 successive weeks. The common carotid artery, external and internal carotid arteries of rats in the latter two groups were exposed. The stress way of sham-operation+ stress group was the same as that of MCAO+ stress group. ②The neurological status grading and motor performance evaluation (screen test, rota-rod test and balance beam test) were conducted in rats with simple sham-operation group and MCAO group before, 1st and 28th days after modeling. Depression-like behavior test was performed in the rats of each group by sucrose preference test and open field test at the end of the experiment. MAIN OUTCOME MEASURES: Changes of depression-like behaviors of rats in each group. RESULTS: Forty-eight rats were involved in the experiment. Two rats with meningeal irritation sign were excluded from simple MCAO group, and one rat in the MCAO+stress group died of some unclear causes during the experiments. The other 45 rats entered the stage of finial analysis. ① Depression-like behavior assessment results: The rats in the MCAO+ stress group had a significantly decreased preference for sucrose solution, crossing and rearing scores, and increased immobility duration after the 14-day restraint stress, compared with those in other three groups (all P < 0.05). ②The neurological status grading and motor performance evaluation: There were significant differences in the two indexes of rats in the simple MCAO group before, 1st and 28th days after modeling (P < 0.01), while there was no significant difference before and 28th days after modeling (P > 0.05). There were no significant changes in sham-operation group at each time point (P > 0.05). CONCLUSION: After being exerted restraint stress, the rats with transient focal ischemic injury may show obvious depression-like behaviors. Therefore, restraint stress can be used as a novel animal modeling method for further studying biological mechanism in central nervous system of post-stroke depression animals.     

Naoxintong dose effects on inflammatory factor expression in the rat brain following focal cerebral ischemia

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     

Effects of polygonatum sibiricum polysaccharide on learning and memory in a scopolamine-induced mouse model of dementia★

BACKGROUND： Learning and memory processes are accompanied by complex neuropathological and biochemical changes. Free radicals play an important role in learning and memory damage. OBJECTIVE： To observe the effects of polygonatum sibiricum polysaccharide （PSP） in comparison with vitamin 12 on inhibiting free radical damage, as well as improving the degree of cerebral ischemia and learning and memory in a scopolamine-induced mouse model of dementia. DESIGN： Randomized controlled animal study. SETTINGS： Department of Pharmacology, Taishan Medical College; Shandong Jewim Pharmaceutical Co., Ltd. MATERIALS： A total of 105 healthy Kunming mice, comprising 90 males and 15 females that were clean grade, were provided by the Animal Center of Taishan Medical College. PSP （extracted and purified by Huangjing, Taishan） was provided by the Department of Traditional Chinese Medicine, Taishan Medical College （purity of 79.6% by using a phenol-concentrated sulphate acid method）, and hydrogen bromine acid scopolamine injection solution （SCO） by Shanghai Hefeng Pharmaceutical Co., Ltd. METHODS： This study was performed at the Pharmacological Laboratory of Taishan Medical College from March to June 2007. （1） A total of 75 healthy Kunming male mice of clean grade were randomly divided into a normal control group, positive control group, and low-dosage and high-dosage PSP groups, with 15 mice in each group. Mice in both the low-dosage and high-dosage PSP groups were intragastrically administered 0.5 g/kg and 2.0 g/kg PSP, respectively. Mice in the positive control group were intragastrically administered 0.5 g/kg vitamin 12. In addition, mice in both the normal control group and model group were intragastrically administered the same volume of saline, respectively, once a day for 7 consecutive days. One hour after the final administration on day 6, mice in the positive control group, model group, low-dosage and high-dosage PSP groups were subcutaneously injected with 3.0 mg/kg SCO, while mice in the no     

Hepatocyte growth factor gene transfer effects on the femoral and intramuscular nerve in a canine model of lower limb ischemia*☆

BACKGROUND： Recent advancements in gene therapy have provided new methodology for treating ischemia in lower extremities. Gene transfer of angiogenic factors to ischemic tissues may promote local proliferation of new vessels and form collateral circulation. OBJECTIVE： To observe histopathological changes in the femoral and intramuscular nerve three months after intramuscular injection of hepatocyte growth factor （HGF） into the peripheral skeletal muscle in a canine model of lower limb ischemia. DESIGN： Randomized occlusion modelled and verification animal study. SETTING： Experimental Center, Lanzhou General Hospital of Lanzhou Military Area Command of Chinese PLA. MATERIALS： This study was performed at Animal Experimental Center, Lanzhou General Hospital of Lanzhou Military Area Command of Chinese PLA from September to November 2006. A total of eight male mongrel dogs, weighing 12–15 kg and 1.5–3 years of age, were selected for this study. This experimental study was in accordance with local ethics standards. Recombinant plasmid carrying HGF （pUDKH） and occlusion model plasmid （pUDK） were provided by the Third Laboratory of Radiation Medical Institute, Academy of Military Medical Sciences of PLA. METHODS： Grouping and model establishment： under anesthesia, complete vascular occlusion models were established on the left lower extremities. The experimental dogs were randomly divided into a model group and a pUDKH treatment group, with four dogs in each group. Dogs in the pUDKH group were injected with 0.15 mg/kg pUDKH. Ten minutes later, intramuscular injections were performed at three spots into the peripheral skeletal muscle of the left hind limb, as well as lateral injections at two spots. The injection volume at each spot was 0.2 mL. Dogs in the model group were injected with pUDK, and dosage and injection method were identical to the treatment group. MAIN OUTCOME MEASURES： Histopathological changes in the femoral nerve, as well as internal and external intramuscular nerve tissue     

Effect of cyclovirobuxine D on human growth-associated protein 43 and neurocan expression in ischemic brain tissue of stroke-prone renovascular hypertensive rats*★

BACKGROUND： Experimental data indicate that human growth-associated protein 43 mRNA expression coincides with axonal growth during nerve ganglion development; while neurocan, secreted from astrocytes, can inhibit sprouting and elongation of the axonal growth cone. OBJECTIVE： To verify regulatory effects of cyclovirobuxine D （CVB-D） extracted from Chinese box branchlet on human growth-associated protein 43 （GAP-43）, and neurocan expression in brain tissue of stroke-prone renovascular hypertensive （RHRSP） rats, at different time points after cerebral ischemia/reperfusion. DESIGN： Randomized grouping design and controlled animal study. SETTING： This study was performed at the Center of Guangdong Hospital of Traditional Chinese Medicine （a national key laboratory） from March 2003 to September 2006. MATERIALS： 100 healthy male Sprague-Dawley rats, aged 2 3 months and weighing 90-120 g, were selected for this study. CVB-D was provided by Nanjing Xiaoying Pharmaceutical Factory （Batch number： 307701）. METHODS： The initial tip of renal arteries was clamped bilaterally for 10 weeks to establish the RHRSP model. 100 RHRSP rats were randomly divided into 4 groups： naive group （n = 10）, sham surgery group （n = 10）, CVB-D group （n = 40）, and lesion group （n = 40）. Rats in the naive group did not undergo any treatment, and cervical vessels of rats in the sham surgery group were exposed, but not blocked. The right middle cerebral artery of rats in the CVB-D group and lesion group were occluded to establish cerebral ischemia. Rats in the CVB-D group were intraperitoneally injected with CVB-D （6.48 mg/kg） every day and with saline （1.5 mL/injection） twice a day. Rats in the lesion group were intraperitoneally injected with saline （2 mL/injection）. MAIN OUTCOME MEASURES： Immunohistochemistry was applied to detect GAP-43 and neurocan expression in the ischemic penumbra region of CVB-D and lesion brains at 2 hours post-cerebral ischemia and at 1, 7, 14, and 30 days po     

miRNA与脑缺血关系的研究进展

微小核糖核酸（microRNA,miRNA）是一类非编码的小分子RNA,它们基于与靶mRNA的序列互补来降解mRNA和抑制蛋白质翻译,从而影响靶蛋白的表达。miRNA与脑缺血的发生、发展密切相关,可成为诊断脑缺血的生物标记物。现对miRNA与脑缺血的相关性做一综述,为脑缺血的临床预防、诊断、治疗提供依据和思路。     

伴后循环梗死烟雾病一例

患者男性,37岁。主因头痛、视物模糊7d,于2012年6月26日入院。患者入院前7d无明显诱因出现左侧额部疼痛、视物模糊,无言语和肢体症状,无恶心、呕吐、抽搐、意识障碍、大小便失禁等症状。当地医院排除眼科疾病,遂至我院就诊,头部MRI检查显示左侧颞枕叶梗死,为进一步诊断与治疗收入院。既往糖尿病10年,口服格列齐特,平时未规律监测血糖。否认高血压、冠心病、胃病、自身免疫性疾病病史,否认肝炎、结核病等传染病病史,否认手术史、外伤史。无家族遗传性疾病病史。吸烟10余年（3～4支,d）,偶饮酒。     

Ultrastructural changes of rat cortical neurons following ligustrazine intervention for cerebral ischemia/reperfusion injury*★

BACKGROUND： Ligustrazine can reduce the production of free radicals and the content of malonaldehyde, and improve the enzymatic activity of adenosine-triphosphate in cerebral anoxia. It also can increase the expression of heat shock protein-70 and Bcl-2, thus alleviating brain tissue injury caused by cerebral ischemia/reperfusion. This study aimed to address the question of whether ligustrazine can protect the membrane structure of neurons. OBJECTIVE： To establish rat models of cerebral ischemia/reperfusion, observe the membrane structure and main organelles of neurons with electron microscope after ligustrazine intervention, and to analyze the dose-dependent effects of ligustrazine on neuronal changes. DESIGN： A randomized controlled study. SETTING： Department of Anatomy Research and Electron Microscopy, Hebei North University. MATERIALS： Forty Wistar rats of SPS grade, weighing 180-250 g and equal proportion of female and male, were provided by Hebei Medical University Animal Center （No. 060126）. The ligustrazine injection （40 g/L, No. 05012） was produced by Beijing Yongkang Yaoye. LKB4 Ultramicrotome was purchased from LKB Company in Sweden. JEM100CXII electron microscope was purchased from JEOL in Japan. METHODS： The experiment was performed in the Laboratory of the Department of Anatomy and Electron Microscopy, Hebei North University from June to August 2006. （1） Wistar rats were allowed to adapt for 3 days, and were then randomly divided into four groups, according to the numeration table method： normal group, model group, low-dose ligustrazine group, and high-dose ligustrazine group. There were 10 rats in each group. （2）Rats in the model group, low-dose ligustrazine group, and high-dose ligustrazine group underwent cerebral ischemia/reperfusion model, according to Bannister＇s method. The carotid artery was opened for reperfusion after 90 minutes of cerebral ischemia. Samples were collected from the cerebral cortex after 24 hours. Animals from the ligustrazine low-dose group