Analysis of Crucial Transcription Factors of Berberine Against Cerebral Ischemia Based on Transcriptomics and Proteomics / 中国实验方剂学杂志

ObjectiveOn the basis of determining the protective effect of berberine （BBR） on cerebral ischemia， crucial transcription factors （TFs） of BBR against cerebral ischemia was identified by using transcriptome and proteome sequencing. MethodThe model of middle cerebral artery occlusion （MCAO） was established by thread embolization. The sham operation group， model group， low-dose group of BBR （dose of 37.5 mg·kg-1·d-1） and high-dose group of BBR （75 mg·kg-1·d-1） were set up. The rats were killed after continuous intragastric administration for 7 days. The pharmacodynamics was evaluated by Longa score and cerebral infarction rate， and the expressions of inflammatory cytokines， such as interleukin （IL）-1β， tumor necrosis factor （TNF）-α and monocyte chemotactic protein-1 （MCP-1） were measured by enzyme-linked immunosorbent assay （ELISA）. Then， RNA-Seq technique was used to detect the differentially expressed genes （DEGs） before and after BBR intervention， and DAVID 6.8 was used for enrichment analysis of DEGs. CatTFREs technique was used to detect differential TFs before and after BBR intervention， and DAVID 6.8 and STRING 11.0 were used for enrichment analysis and TFs association analysis. Finally， by integrating the activity of TFs and the changes of downstream target genes， crucial TFs were identified and the related regulatory network was constructed by Cytoscape 3.7.1. ResultCompared with the sham operation group， the neurological impairment was significant in the model group （P<0.01）， and compared with the model group， the low and high dose BBR groups could significantly reduce the neurological function damage （P<0.01） and decrease the rate of cerebral infarction （P<0.01）. Transcriptome data analysis showed that BBR was involved in the recovery process after cerebral ischemia mainly by affecting cell adhesion， brain development， neuron migration， calcium signaling pathway， cyclic adenosine monophosphate （cAMP） signaling pathway， inflammatory response and other related functions and signaling pathways. Proteomic data analysis showed that the differentially expressed TFs after BBR intervention interfered with cerebral ischemia mainly by regulating cell differentiation， immune system process， cell proliferation and other biological processes. In addition， integration analysis of TFs and DEGs revealed that transcription factor CP2-like 1 （TFCP2L1）， nuclear factor erythroid-2 like 1 （NFE2L1）， neurogenic differentiation protein 6 （NeuroD6） and POU domain， class 2， transcription factor 1 （POU2F1） were crucial TFs against cerebral ischemia-reperfusion injury mediated by BBR. ConclusionBBR has obvious protective effect on cerebral ischemia-reperfusion injury and its crucial TFs include TFCP2L1， NFE2L1， NeuroD6 and POU2F1.

Spectrum-effect relationship of the blood-activating efficacy of Notoginseng Radix et Rhizoma / 中国中药杂志

This study aims to establish the high-performance liquid chromatography(HPLC) fingerprints of different batches of Notoginseng Radix et Rhizoma, determine their pharmacodynamic indexes of promoting blood circulation, and explore the spectrum-effect relationship between the chemical components of Notoginseng Radix et Rhizoma and the efficacy of promoting blood circulation. Firstly, the HPLC fingerprints of different batches of Notoginseng Radix et Rhizoma were established. Then, the pharmacodynamic indexes were determined after the capillary coagulation experiment and the cerebral ischemia-reperfusion in rats, including capillary coagulation time, percentage of cerebral ischemic area, cerebral water loss rate, and brain-body index. Afterward, the partial least-squares method was used to explore the spectrum-effect relationship between the chemical components of Notoginseng Radix et Rhizoma and the pharmacodynamic indexes. The results showed that this study successfully established the HPLC fingerprints of different batches of Notoginseng Radix et Rhizoma, found 23 common peaks, and identified 12 of them, all of which were saponins. The method was proved stable and reliable. Both the capillary coagulation experiment and the middle cerebral artery occlusion(MCAO)-induced cerebral ischemia-reperfusion experiment on rats revealed that there were obvious differences in the pharmacodynamic indexes of different batches of Notoginseng Radix et Rhizoma. The relationships between 23 common components of Notoginseng Radix et Rhizoma in different batches and the pharmacodynamic indexes were discussed by means of spectrum-effect correlation analysis, of which 17 components had positive effects while 6 components had negative effects on the pharmacodynamic indexes. This study provides a certain reference basis for the clinical rational use and quality control of Notoginseng Radix et Rhizoma.

Improvements of motor and cognitive functions in the rats with permanent middle cerebral artery occlusion treated with acupuncture and rota-rod training / 中国针灸

OBJECTIVE@#To explore the effects on the recovery of the motor and cognitive functions of the rats with permanent middle cerebral artery occlusion (pMCAO) after treated with 's three-needle acupuncture at head acupoints combined with rota-rod training.@*METHODS@#A total of 38 male SD rats were randomized into 3 groups, named a sham-operation group (11 rats), a model group (13 rats) and a treatment group (14 rats). The electrocoagulation method was adopted to establish the model of pMCAO on the right cerebrum. Starting from the 1st day after successful modeling, acupuncture was applied to the "three points of intelligence", the "three points of temporal area" and the "three points of brain". Additionally, the rota-rod training was used. Acupuncture was given once a day and the training was three times a day. In the sham-operation group and the model group, empty grasp fixation was performed when acupuncture was applied in the treatment group, and there was no intervention at the rest of the time. There was 1 day of interval after consecutive 6 days of intervention. Totally, the intervention was for 3 weeks. After modeling, the brain section was collected from 3 rats of each group on the 1st day and was stained with TTC to observe the condition of cerebral ischemia. From day 1 to 7, the neurological function score was evaluated. The footprint analysis and rota-rod test were performed on day 1, 7, 14 and 21. The Morris water maze test was performed from day 22 to 26.@*RESULTS@#Compared with the sham-operation group, cerebral ischemia presented obviously, the score of neurological function was increased, the back front distances on the left were increased on day 1, 7 and 14 separately, the revolutions per minute (RPM) of the rota-rod were reduced at each of the above 4 time points, the latency of navigation trial was increased and the movement time percentage in Q3 quadrant of spatial probe trial was reduced in the model group (0.05), the score of neurological function was reduced on day 6, the back front distance on the left was reduced on day 14, RPM of the rota-rod were increased on day 14 and 21, the latency of navigation trial were reduced from day 23 to 25 and the movement time percentage in Q3 quadrant of spatial probe trial was increased in the treatment group (<0.01, <0.05).@*CONCLUSION@#'s three-needle acupuncture at head acupoints combined with rota-rod training improve the behavioral performance of pMCAO rats and promote the recovery of motor and cognitive functions.

Detection of hypothalamic infarction in intraluminal middle cerebral artery occlusion model rat by DWI scanning / 上海交通大学学报（医学版）

Objective: To detect and evaluate the hypothalamic infarction in middle cerebral artery occlusion (MCAO) model rat. Methods: For 15 Sprague-Dawley rats weighed 200-250 g, aged 6-8 months, their right middle cerebral artery was occluded for 90 min by a silicon-coated 4-0 nylon filament and reperfused. Sprague-Dawley rats underwent diffusion weighted MR imaging (DWI) scanning (at 1 h and 24 h after reperfusion) and 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining (at 24 h after reperfusion) to determine the hypothalamic and cerebral infarct volume. The relationship between hypothalamic infarct volume and cerebral infarction volume was analyzed by DWI scanning. The results of TTC staining were compared with those of 24 h DWI scanning. Results: Fifteen Sprague-Dawley rats successfully received intraluminal MCAO/reperfusion procedures. The incidences of hypothalamic infarction on brain DWI scanning and TTC staining were 100% and 40% at 24 h after reperfusion, respectively. Therefore, DWI scanning was more sensitive than TTC staining to detect hypothalamic injury (P=0.001). The hypothalamic infarct volume on DWI scanning was (8.59±2.89) mm3 and (11.65±3.19) mm3 at 1 h and 24 h after reperfusion, respectively. On DWI scanning, hypothalamic and cerebral infarct volume at 24 h after reperfusion were correlated with each other significantly (r=0.573, P=0.025), so were the increases of hypothalamic and cerebral infarct volume (r=0.554, P=0.032) from 1 h to 24 h. Conclusion: DWI scanning was more sensitive than TTC staining to detect hypothalamic injury in intraluminal transient MCAO model. Hypothalamic and cerebral infarct volume were correlated with each other.

Regulation of thin recipe of Buyang Huanwudecoction on Cdk5 expression of rats after cerebral ischemia / 中国药理学通报

Aim To evaluate the regulation of thin recipe of Buyang Huanwu decoction on cyclin-dependent kinase 5(Cdk5)expressions in hippocampus tissue of rats after cerebral ischemia.Methods Male SD rats were divided into sham-operation group,MCAO group,Buyang Huanwu decoction group(ig.3.15 g·kg-1)and its thin recipe composition group(ig.2.41 g·kg-1).Each group was then divided into five subgroups based on the time after administration for 1,3,7,14,28 d respectively.Cdk5 protein and mRNA levels in each group were examined by using immunohistochemistry,Western blot and real-time PCR respectively.Results The up-regulation of Cdk5 was observed in model rat hippocampus after cerebral ischemia 1 day,and kept increasing with the aggravation of ischemia injury,the peaked expression was observed after 7～14 d,while the downtrend was observed after 28 days compared with the corresponding sham-operation groups(P0.05).Conclusion The thin recipe of Buyang Huanwu decoction could exert the protective effect by regulating Cdk5 after cerebral ischemia.

UHPLC-LTQ-Orbitrap-based metabolomics coupled with metabolomics pathway analysis method for exploring the protection mechanism of Kudiezi injection in a rat anti-ischemic cerebral reperfusion damage model / 中国天然药物

Kudiezi injection has been used extensively in the treatment of cerebrovascular and cardiovascular diseases. However, its therapeutic effects and underlying mechanism of action are not fully understood. The aim of the present study was to clarify the protective mechanisms of Kudiezi injection on cerebral ischemic injury, using metabolomics methods. Middle cerebral artery occlusion (MCAO) was introduced in rats to build the cerebral ischemic damage. UHPLC-LTQ-Orbitrap-based analytical method was established for analysis of the metabolites. The raw mass data of all samples were normalized with Sieve 2.2 software and then introduced to orthogonal partial least squares discriminant analysis (OPLS-DA) model. Finally, 23 metabolites in plasma (15 were tentatively identified) were chosen as potential biomarkers, according to accurate mass measurements (< 5 ppm), MS/MS fragmentation patterns, and diagnostic product ions. Furthermore, on the basis of metabolic pathway analysis via metabolomics pathway analysis (MetPA), we first discovered that the protection mechanism in anti-ischemic cerebral reperfusion damage of Kudiezi injection was possibly related to the biosynthesis of phenylalanine, tyrosine, and tryptophan. The present study provided a useful approach for exploring the mechanism of ischemic stroke and evaluating the efficacy of Kudiezi injection or other traditional medicines.

A modified method for common carotid artery puncture in the establishment of a rat model of middle cerebral artery occlusion / 中国实验动物学报

Objective To compare the timeliness, success and mortality rates between the modified carotid artery puncture method ( MCAPM) and standard suture method ( SSM) in the establishment of rat model of a middle cerebral ar?tery occlusion ( MCAO) . Methods Thirty?two male rats were randomly and equally assigned into MCAPM group and SSM group. The MCAO models were established by inserting a thread into the common carotid artery ( CCA) . 24 h after modeling, the rats of the two groups were evaluated with Bederson neurological scores, and the modeling success rate and mortality rate were analyzed. Results The suture insertion times, success rates and mortality rates of the MCAPM vs. SSM groups were (82?3 ±17?4) s versus (164?6 ± 22?0) s (P0?05), and 6?25% versus 18?75% (P>0?05). Conclusions MCAPM can be used to establish the rat model of MCAO due to its simplicity, mild wound and feasibility.

Huo-Luo-Xiao-Ling-Dan Plays a Protective Role in Ischemic Brain in Rats via Inhibiting Inflammatory Responses after Stroke / 浙江中医药大学学报

[Objective]To observe whether Huo-Luo-Xiao-Ling-Dan(HLXLD) can inhibit the inflammation after ischemic stroke. [Methods] Focal cere-bral ischemia was induced by middle cerebral artery occlusion (MCAO) for 2 hours fol owed by 24 or 48 hours reperfusion in male rats. We treated is-chemic stroke rats with HLXLD(0.5, 2.0 and 6.0g·kg-1) by daily gavages beginning at the onset of stroke. The control group received the vehicle. [Re-sults] HLXLD 2.0, 6.0/kg treatment significantly attenuated the infarct volume, neurological deficits, upregulation of proinflammatory cytokines in the brain of rats after stroke compared with that of non-HLXLD group. Furthermore, the activation of NF-κB signaling was significantly reduced in HLXLD treated rats after stroke compared to that of non-HLXLD group. [Conclusion] Our data demonstrated that HLXLD can play an important protective role in brain injury after ischemic stroke via inhibiting inflammatory responses in the brain.

Effects of the effective components group of Xiaoxuming decoction on MCAO rats / 中国药学杂志

OBJECTIVE: To investigate the protective effects of the effective components group of Xiao-Xu-Ming decoction (XXM) on focal cerebral ischemia rats. METHODS: The model of focal cerebral ischemia was made by middle cerebral artery occlusion (MCAO) with nylon suture. The neuroethological score and the staying time on slope board were gotten after 48 h of the operation. The percentage of cerebral infarction volume to total brain volume was calculated by TTC staining. Furthermore, the content of MDA, the activities of SOD and GSH-Px, and the activity of NOS in the brain tissue were detected by photospectrometer analysis system. RESULTS: The effective components group of Xiao-Xu-Ming decoction could significantly reduce the scores of neurological deficits , alleviate the cerebral infarction volume, improve the activity of SOD, reduce the content of MDA, and decrease the activity of iN-OS, but have no effect on the activity of GSH-Px. CONCLUSION: The effective components group of Xiao-Xu-Ming decoction may attenuate the focal cerebral ischemia injury in rats, and the mechanism is related to regulate the balance between oxidation and anti-oxidation and decrease the activity of iNOS in the brain tissue. Copyright 2012 by the Chinese Pharmaceutical Association.

In vivo Tracking of Human Neural Stem Cells Following Transplantation into a Rodent Model of Ischemic Stroke

BACKGROUND AND OBJECTIVES: Ischemic stroke caused by middle cerebral artery occlusion (MCAo) is the major type of stroke, but there are currently very limited options for cure. It has been shown that neural stem cells (NSCs) or neural precursor cells (NPCs) can survive and improve neurological deficits when they are engrafted in animal models of various neurological diseases. However, how the transplanted NSCs or NPCs are act in vivo in the injured or diseased brain is largely unknown. In this study, we utilized magnetic resonance imaging (MRI) techniques in order to understand the fates of human NSCs (HB1.F3) following transplantation into a rodent model of MCAo. METHODS AND RESULTS: HB1.F3 human NSCs were pre-labeled with ferumoxides (Feridex(R))-protamine sulfate complexes, which were visualized and examined by MRI up to 9 weeks after transplantation. Migration of the transplanted cells to the infarct area was further confirmed by histological methods. CONCLUSIONS: Based on these observations, we speculate that the transplanted NSCs have the extensive migratory ability to the injured site, which will in turn contribute to functional recovery in stroke.

CRMP-2 is involved in hypoxic preconditioning-induced neuroprotection against cerebral ischemic injuries of mice / 基础医学与临床

Objective To investigate whether conventional protein kinase C (cPKC ) βⅡ-interacting collapsin response mediator protein-2 (CRMP-2) provides neuroprotection against cerebral ischemic (I) injuries. Methods Male BALB/c mice were randomly divided into normoxic control (Nor) , HPC, Nor + Sham, HPC + Sham, Nor + I and HPC + I groups (n = 6 per group). Using our HPC and MCAO mouse models, we applied immunoprecipita-tion, two-dimensional electrophoresis and mass spectrometry to characterize cPKCβⅡ-interacting proteins and combined with SDS-PAGE and Western blot to quantitatively analyze CRMP-2 phosphorylation and degradation levels in the brain of mice after HPC and MCAO. Results The expression level of 10 cPKCβⅡ-interacting proteins changed obviously in cerebral cortex of HPC mice when compared with Nor group. One of these proteins, CRMP-2 protein level increased in particulate fraction and decreased in cytosolic fraction of cerebral cortex of HPC mice. CRMP-2 phosphorylation level in ischemic core (Ic) of cerebral cortex decreased significantly ( P < 0. 05 , n = 6) as compared with that of Nor + sham group, but CRMP-2 phosphorylation level in HPC +I group increased significantly as compared with that of Nor +I group ( P < 0. 05, n = 6). In ischemic cortex, CRMP-2 degradation (proteolysis) was observed as the appearance of 55 ku breakdown products (BDP). However, the CRMP-2 degradation level, BDPs products decreased significantly in penumbra ( P) of ischemic cortex from HPC +I group when we compared with that of Nor +I group (P < 0. 05, n = 6 ). Conclusion CRMP-2 is involved in attenuating the decrease of CRMP-2 phosphorylation in ischemic core and in inhibiting its degradation in penumbra of cerebral cortex of mice thereby to lessen the ischemic injuries.

Effects of Constraint-induced Movement Training on Neurological Medullary Sheath in Rats after Middle Cerebral Artery Occlusion / 中国康复理论与实践

@#Objective To study the effects of constraint-induced movement train (CIMT) on the neurological medullary sheath in the rats after middle cerebral artery occlusion (MCAO). Methods 55 SD rats were randomly divided into CIMT group and nature recovery (NR) group after MCAO. The CIMT group were trained with balance beam and rolling cage everyday, with restrictting the movement of the intact upper limbs. The NR group lived in the same condition. The rats in CIMT group were assessed with ethology 5 d, 10 d, 15 d, 30 d and 60 d after operation respectively. At last, 5 rats of each group were checked with MRI, then they were immolated for myelin staining. Results The balance and muscle strength of CIMT group improved better compared with the NR ones (P<0.05), as well as the diameter and the demyelination of neurofibril in the infarcted area. Conclusion CIMT can collect more functional neurofibra and decrease myelinolysis.

Neuroprotective Effects of different doses of BPI-1095 in Focal Cerebral Ischemia Rats / 中国康复理论与实践

@#ObjectiveTo investigate the neuroprotective effects of different doses of BPI-1095 on infarct volume and neurological outcome in middle cerebral artery occlusion(MCAO) rats.MethodsCerebral ischemia model was induced with MCAO in adult male SD rats. 10 minutes after surgery, rats were randomly subjected into six groups with 15 rats in each group. Each rat has been given different dosage tested medication and was sacrificed 24 h after treatment. Neurological functional behaviour tests were performed 4 h and 24 h after treatment. After the final behaviour test, 7 or 8 rats (remain 5 rats for brain tissue stain) were randomly picked up from each group. Their infarction volume was measured with image analysis system after 2% triphenyl-tetrazolium chloride (TTC) stain. ResultsHigh dose (240 mg/kg) and moderate dose (80 mg/kg) of BPI-1095 were able to improve the neurological deficit in MCAO rats (P<0.05, vs vehicle-treated group), as well as they decrease the infracted volume (P<0.05, vs the vehicle-treated group ) 24 h after ischemia.Conclusion80～240 mg/kg BPI-1095 is able to improve neurological deficit effectively and reduce infarct volume significantly.

Advance in Cerebral Ischemic Model with Middle Cerebral Artery Occlusion in Rats(review) / 中国康复理论与实践

@#The middle cerebral artery occlusion(MCAO) in rats remained a focus cerebral ischemic model that is non-incisioned,reliable,as well as the ischemic and refusion time can be controlled,which is widely used since it was created.However,because it is needed complex operations,associatied with many factors,it is difficult to establish.Many scholars have modified the operation,shape of the occlusion line,as well as the variety,narcotic drugs and so on.

Effect of transplanted human bone marrow mesenchymal stem cells on behavioral changes of cerebral ischemic rats / 基础医学与临床

Objective Investigate the behaviors of cerebral ischemic rats after treatment with bone marrow mesenchymal stem cells(BMSCs).Methods Bone marrow was collected and BMSCs were separated and cultivated.Twenty-four adult male Sprague-Dawley rats were performed transient(2 hours) middle cerebral arterial occlusion(MCAO) and then divided into treated group(n=12) and control group(n=12).All rats received corresponding behavioral training before surgery,15 ?L hBMSCs(2?1010cells/L) and D-hanks(15 ?L) were injected into the brain cortex after 24 h of MCAO.Morris water maze test,NSS,Rotarod test and adhesive-removal test were performed serially and cyclically from the 4th day after transplantation.Results Since the 8th day after transplantation,the mean escape time and the mean swimming distance of treated group significantly are shorter than control's in Morris water maze test(P

Rehabilitative effects and pathological changes in rats after cerebral infarction / 中国康复理论与实践

@#ObjectiveTo study the rehabilitative effects and pathological changes in rats after acute cerebral infarction. Methods 30 male Wister rats were randomly divided into 3 groups :Group A(sham group),Group B(model group) and Group C(rehabilitation group). Animal model was made by the middle cerebral artery occlusion(MCAO).For each group, Bederson Neural Function was scored and balancing wood,rotating bar,and net screen were tested at 24 hours,3 days and 7 days after operation respectively. On the 7th day after operation, pathological change of brain tissue was observed. ResultsCompared with Group A, Bederson Neural Function scores of Group B,C indicated significant differences at each time (P<0.01).The abilities of grasping, walking and coordinating of all the groups after 24 hours by operation handicapped, however with time continuing,every function of Group A restored and that of Group B or C improved partly,but showed significant difference compared with Group A(P<0.01).After 3 days by operation,balancing wood test of Group C was better than that of group B(P<0.05),after 7 days,except Bederson Neural Function score,there were difference between Group C and B(P<0.05 or P<0.01).After 7 days by operation,compared with Group A,brain tissue of infarction area in Group B indicated significantly edema, neural cells decreased. Compared with Group B, the edema in Group C decreased and neural cells increased.ConclusionsRehabilitation therapy can improve the MCAO rats' ability of equilibrating, grasping and walking, and decrease edema, increase neural cells in infarction areas.

The Development of Apoptosis and DNA Fragmentation in Transient Ischemic Model in Rats, and Roles of Dexamethasoneand Hypothermia / 대한마취과학회지

BACKGROUND: Neuronal cell death after brain ischemia occurs predominately by necrosis, whereas only a minor fraction of cell death may occur through apoptosis. Authors investigated DNA fragmentation and apoptotic morphology in the brain cell to determine whether apoptosis contributes to the progression of an ischmic lesion. This study was conducted to determine the effects of dexamethasone and hypothermia on moderate brain ischemic injury by middle cerebral artery occlusion (MCAO) in rats. METHODS: Thirty Sprague-Dawley rats (220 - 280 g) were used. Anesthesia was induced and maintained with isoflurane in oxygen. MCAO was induced by intraluminal monofilament nylon. All rats were divided randomly into three groups. In group I (n = 10), normal saline 1 ml was injected intravenously 10 minutes before MCAO. In group II (n = 10), dexamethasone 3 mg/kg was administered and in group III (n = 10), body temperature was maintained at 32degreesC. After 60 minutes of MCAO, all rats that recovered from anesthesia were returned to cages. After 24 hour reperfusion, brain tissue was quickly removed and cerebral hemispheres were separated. Lesion volumes were measured by TTC staining. TUNEL reactivity was examined in the cortical infarction lesion, and rat brain DNA was run on agarose gel electrophoresis to detect DNA fragmentation. RESULTS: Apoptosis and DNA fragmentation in the nucleus developed in the hippocampal area after transient ischemia in rats. Dexamethasone did not prevent the development of apoptosis and DNA fragmentation in transient brain ischemic rats. Moderate hypothermia could prevent the development of apoptosis and DNA fragmentation in transient brain ischemic rat. CONCLUSIONS: Apoptosis may represent a mode of ischemic cell death, and dexamethasone couldn't prevent apoptotic change in the ischemic brain insult. Moderate hypothermia (32degreesC) was a specifically effective procedure to reduce the development of apoptotic change in ischemic insults.

The Time Evolution of Cerebral Infarction in Rat Middle Cerebral Artery Occlusion

For the assessment of clinical management, for the confirmation of clinical findings, and also for the evaluation of new diagnostic techniques to determine the location as well as the extent of area of infarction on evolution in cerebral tissue is essential. Sequential evolution of infarction in 2% 2, 3, 5-triphenyltetrazolium hydrochloride(TTC) staining and its concomitant neurological changes were investigated in the rat following left middle cerebral artery occlusion(MCAO). In addition, the pathological evaluation was performed in the same coronal cut slice of each TTC staining. The results were: 1) In the TTC staining method, the cerebral infarction was not found in the 2 hour group rats, and appeared as white or pink color after 4 hours. 2) The size of infarction was significantly correlated with time of occlusion before sacrifice(p<0.05). The size increment was most obvious between 8 hour and 24 hour groups. 3) The time evolution of cerebral infarction was most prominent in the cerebral cortex, and was minimal in the basal ganglia which are supplied by the 'end artery'. 4) The cerebral infarction appeared first in the coronal cuts at the 4, 6, and 8mm from the frontal pole, which is the main territory of MCA. 5) The cerebral infarction, mainly presented in the 4, 6, and 8mm coronal cuts from the frontal pole, extended from the pyriform cortex to the fronto-parietal cortex. It also appeared at 2, 10mm coronal cuts from the frontal pole in 24 hour group. 6) The neurologic sign was not correlated to the time of MCAO and the size of infarction on evolution. Therefore, the prediction of location and size of area of infarction on evolution was impossible by the neurological status. 7) The histopathological change was detected as early as in 2 hours. However, hematoxylin and eosin(H & E) stained sections showed only subtle changes, such as small irregular areas of cortical spongiosis and neuronal shrinkage up to 8 hours. There was no significant difference between lesion areas of 2 hour and 8 hour groups. The pathological findings of 24 hour group rats was definite and appeared as a central area of coagulation necrosis and rarefaction surrounded by a zone of peripheral spongiosis.