Different levels of thyroid hormones between impaired fasting glucose and impaired glucose tolerance: free T3 affects the prevalence of impaired fasting glucose and impaired glucose tolerance in opposite ways.

CONTEXT: There is an association between thyroid disorders and diabetes mellitus. OBJECTIVE: To investigate thyroid hormone levels in different glucose metabolic statuses, analyse relationships between thyroid hormone levels and different categories of prediabetes and metabolic parameters within a large euthyroid nondiabetic population. METHODS: A total of 3328 subjects without diabetes or thyroid dysfunction were included in this cross-sectional study. Subjects were divided in to four groups [normal glucose tolerance (NGR), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and combined glucose intolerance (CGI)] according to the results of oral glucose tolerance test. Participants were then divided into four groups according to the quartile of free T3 (FT3) in their blood. RESULTS: Subjects with IFG had higher levels of FT3 and ratio of FT3 to FT4 (FT3/FT4), but lower level of free T4 (FT4) than subjects with IGT. FT3/FT4 was negatively associated with postprandial plasma glucose (PPG) [standardized ß (ß) = -0·087; P < 0·001]. The prevalence of IFG and CGI was increased with the level of FT3, while the prevalence of IGT was decreased with the level of FT3 (P for trend: <0·001, 0·003 and <0·001, respectively). FT3 was negatively associated with the risk of IGT (OR = 0·409, 95% CI 0·179-0·935), whereas FT4 was positively associated with the risk of IGT (OR = 1·296, 95% CI 1·004-1·673). CONCLUSIONS: Free thyroid hormone levels were different between subjects with IFG and IGT. FT3 affects the prevalence of IFG and IGT in opposite ways. The difference in thyroid hormone levels may play an important role in the different pathological mechanisms of IFG and IGT.

Chemical Characteristics and Comparison of Schizonepetae Herba and Schizonepetae Herba Carbonisata by Combination of GC-MS and UHPLC-MS Strategies.

BACKGROUND: Schizonepetae Herba (SH, Jingjie) and Schizonepetae Herba Carbonisata (SHC, Jingjie Tan) are two different forms of the same herbal material, with SHC being the processed product of SH. The different clinical efficacies of SH and SHC may be caused by changes in their chemical compositions. Despite this, there have been few studies that have reported on the comparative identification of SH and SHC. Therefore, the aims of this experiment are to investigate the differential changes of non-volatile and volatile components before and after SH processing. OBJECTIVES: To establish combination strategies for identifying the chemical markers in SH and SHC using ultra-HPLC-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) and headspace gas chromatography-mass spectrometry (HS-GC-MS). METHODS: UHPLC-Q-TOF-MS and HS-GC-MS methods was utilized to comprehensively discriminate between SH and SHC. To identify chemical markers, principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA) were performed on 14 batches of SH and SHC. RESULTS: A total of 71 non-volatile compounds and 81 volatile compounds were tentatively identified in SH and SHC. Among these, 14 non-volatile compounds and 18 volatile oils were found to be potential characteristic markers that can differentiate between SH and SHC. CONCLUSION: The present work provides valuable information for understanding the chemical differences between SH and SHC. The results obtained from this research may serve as a scientific foundation for comprehensively revealing the mechanisms involved in the carbonizing processing method of stir-frying SH. HIGHLIGHTS: The chemical changes that occur before and after carbonizing SH were investigated using integrated methods based on LC-MS and GC-MS, and chemical markers in SH and SHC were identified.

Herbal Textual Research on Farfarae Flos in Famous Classical Formulas / 中国实验方剂学杂志

By consulting ancient and modern literature， the herbal textual research of Farfarae Flos has been conducted to verify the name， origin， producing area， quality evaluation， harvesting and processing methods， so as to provide reference for the development and utilization of the famous classical formulas containing Farfarae Flos. According to the research， the results showed that Farfarae Flos was first described as a medicinal material by the name of Kuandonghua in Shennong Bencaojing（《神农本草经》）， and the name was used and justified by later generations. The main origin was the folwer buds of Tussilago farfara， in addition， the flower buds of Petasites japonicus were used as medicine in ancient times. The ancient harvesting time of Farfarae Flos was mostly in the twelfth month of the lunar calendar， and the modern harvesting time is in December or before the ground freeze when the flower buds have not been excavated. Hebei， Gansu， Shaanxi are the authentic producing areas with the good quality products. Since modern times， its quality is summarized as big， fat， purple-red color， no pedicel is better. Processing method from soaking with licorice water in the Northern and Southern dynasties to stir-frying with honey water followed by micro-fire in the Ming dynasty， and gradually evolved to the modern mainstream processing method of honey processing. Based on the research results， it is suggested that the dried flower buds of T. farfara， a Compositae plant， should be selected for the development of famous classical formulas containing Farfarae Flos， and the corresponding processed products should be selected according to the specific processing requirements of the formulas， and raw products are recommended for medicinal use without indicating processing requirements.

Herbal Textual Research on Asteris Radix et Rhizoma in Famous Classical Formulas / 中国实验方剂学杂志

By reviewing the ancient and modern literature， the name， origin， scientific name evolution， place of origin， quality， harvesting， processing， efficacy and toxicity of Asteris Radix et Rhizoma（ARR） were systematically sorted out， so as to provide reference for the development and utilization of the relevant famous classical formulas. According to textual research， ARR was first contained in Shennong Bencaojing， all generations are Ziwan for its proper name， and there are still aliases such as Ziyuan， Ziqian and Xiaobianer. Its mainstream origin in successive generations was Aster tataricus， and there are also Ligularia fischeri and others in local area of use. The medicinal parts of ARR are root and rhizome， but in modern times， the rhizome is mostly used for propagation and cultivation， so some of ARR medicinal materials only have the root without the rhizome. The earliest recorded ancient origin of ARR was now Fangxian（Hubei）， Zhengding and Handan（Heibei）， then the range of production areas gradually expanded， the mainstream production areas from the Song dynasty to the Ming and Qing dynasties included Hebei， Jiangsu， Anhui， Henan and other places， since modern times， two major producing areas have been formed in Anguo， Hebei province and Bozhou， Anhui province. From the quality evaluation， it is clear that from ancient times， flexible roots and purple color are the best. The ancient harvesting was mainly in lunar February or March， and then dried in the shade， and the modern harvesting is mostly in spring and autumn， and the roots are braided into pigtails and then dried in the sun or dried in the sun after 1-2 d. The ancient and modern processing method of ARR are basically the same， mainly honey processing， there are still methods of frying， steaming， vinegar sizzling， etc. Based on the results， it is recommended that the dried roots and rhizomes of A. tataricus should be used in clinical and the development of related famous classical formulas， and those whose original formulas specify the processing requirements can be processed according to the relevant requirements， while whose processing requirements are not specified should be used in the form of raw products.

Microvascular Myocardial Ischemia in Patients With Diabetes Without Obstructive Coronary Stenosis and Its Association With Angina

Objective@#To investigate the incidence of microvascular myocardial ischemia in diabetic patients without obstructive coronary artery disease (CAD) and its relationship with angina. @*Materials and Methods@#Diabetic patients and an intermediate-to-high pretest probability of CAD were prospectively enrolled. Non-diabetic patients but with an intermediate-to-high pretest probability of CAD were retrospectively included as controls. The patients underwent dynamic computed tomography-myocardial perfusion imaging (CT-MPI) and coronary computed tomography angiography (CCTA) to quantify coronary stenosis, myocardial blood flow (MBF), and extracellular volume (ECV). The proportion of patients with microvascular myocardial ischemia, defined as any myocardial segment with a mean MBF ≤ of 100 mL/min/100 mL, in patients without obstructive CAD (Coronary Artery Disease–Reporting and Data System [CAD-RADS] grade 0–2 on CCTA) was determined. Various quantitative parameters of the patients with and without diabetes without obstructive CAD were compared. Multivariable analysis was used to determine the association between microvascular myocardial ischemia and angina symptoms in diabetic patients without obstructive CAD. @*Results@#One hundred and fifty-two diabetic patients (mean age: 59.7 ± 10.7; 77 males) and 266 non-diabetic patients (62.0 ± 12.3; 167 males) were enrolled; CCTA revealed 113 and 155 patients without obstructive CAD, respectively. For patients without obstructive CAD, the mean global MBF was significantly lower for those with diabetes than for those without (152.8 mL/min/100 mL vs. 170.4 mL/min/100 mL, P < 0.001). The mean ECV was significantly higher for diabetic patients (27.2% vs. 25.8%, P = 0.009). Among the patients without obstructive CAD, the incidence of microvascular myocardial ischemia (36.3% [41/113] vs. 10.3% [16/155], P < 0.001) and interstitial fibrosis (69.9% [79/113] vs. 33.3% [8/24], P = 0.001) were significantly higher in diabetic patients than in the controls. The presence of microvascular myocardial ischemia was independently associated with angina symptoms (adjusted odds ratio = 3.439, P = 0.037) in diabetic patients but without obstructive CAD. @*Conclusion@#Dynamic CT-MPI + CCTA revealed a high incidence of microvascular myocardial ischemia in diabetic patients without obstructive CAD. Microvascular myocardial ischemia is strongly associated with angina.

Herbal Textual Research on Anemarrhenae Rhizoma in Famous Classical Formulas / 中国实验方剂学杂志

Through reviewing ancient and modern literature， the textual research of Anemarrhenae Rhizoma（AR） has been conducted to verify the name， origin， changes in production areas， quality evaluation， harvesting and processing methods， so as to provide reference for the development and utilization of the famous classical formulas containing AR. Through the herbal textual research， AR was first published in Shennong Bencaojing， and has been used as the proper name for this herb for generations， and the mainstream source of AR used for generations is the rhizome of Anemarrhena asphodeloides. The high-quality production areas that have been revered throughout the ages are Hebei， Shanxi， Shaanxi， Inner Mongolia and Fangshan district of Beijing， etc. In recent times， AR produced in Yixian county of Hebei province（Xiling Zhimu）， is better known and is regarded as a very good source. At present， cultivated AR is mainly produced in Yixian county and Anguo of Hebei province， Bozhou of Anhui province and other places. The medicinal parts of AR in ancient and modern times are all rhizomes， and the quality is better if it has thick flesh， hard wood， yellow outer color and white section color. The harvesting time recorded in ancient medical books is usually in lunar February and August， with exposure to dryness， while modern harvesting is spring and autumn. The processing methods of the past dynasties were mainly to remove the hair when using， avoid iron when cutting， process with wine or salt water， while the two main specifications in modern times are raw and salted products. Based on the systematic research， it is recommended that the dried rhizome of A. asphodeloides in the famous classical formulas be used for AR. If the original formula specifies processing requirements， it should be operated according to the requirements， if the processing requirements are not indicated， the raw products can be used as medicine.

Research progress in the regulation of epigenetics on pancreatic β cell function / 中华内分泌代谢杂志

[Summary] Epigenetics defines heritable changes in gene expression that are not coded in the DNA sequence itself.Three systems,including DNA methylation,RNA-associated silencing and histone modification,are used to initiate and sustain epigenetic silencing.Type 2 diabetes mellitus(T2DM) is a polygenic disorder,which is caused by both genetic and environmental factors.However,pathogenesis of T2DM has not been elucidated.Recent studies have indicated that epigenetics may play an important role in the pathogenesis of T2DM,which is involved in the development and differentiation of β cell,secretion of β cell,insulin sensitivity and so on.Researches related to epigenetics may provide a new measure and target to clarify the pathogenesis of T2DM as well as prevent and treat the disease.

Effects of ropivacaine infiltration combined with dezocine on agitation during recovery from general anesthesia in patients undergoing cerebral surgery / 中华麻醉学杂志

Objective To investigate the effects of ropivacaine infiltration combined with dezocine on the agitation during recovery from general anesthesia in the patients undergoing cerebral surgery.Methods Sixty patients of both sexes,aged 18-64 yr,of ASA physical status Ⅰ or Ⅱ,undergoing elective neurosurgery under general anesthesia,were randomly divided into 4 groups (n =15 each) using a random number table:control group (group C),ropivacaine group (group R),dezocine group (group D),and ropivacaine + dezocine group (group RD).Group C received local infiltration with normal saline 20 ml at 10 min before skin incision,and normal saline 2 ml was injected intravenously at 30 min before the end of operation.The patients received local infiltration with 0.5％ ropivacaine 20 ml at 10 min before skin incision,and normal saline 2 ml was injected intravenously at 30 min before the end of operation in group R.Group D received local infiltration with normal saline 20 ml at 10 min before skin incision,and dezocine 10 mg was injected intravenously at 30 min before the end of operation.The patients received local infiltration with 0.5％ ropivacaine 20 ml at 10 min before skin incision,and dezocine 10 mg was injected intravenously at 30 min before the end of operation in group RD.The time for recovery from anesthesia,extubation time,and development of agitation after extubation in PACU were recorded.Agitation was assessed and scored.Ramsay sedation score and VAS score were recorded immediately after extubation.The development of cardiovascular events and respiratory depression was recorded within 10 min after extubation.Before induction of anesthesia (T0),at the end of surgery (T1) and immediately after extubation (T2),blood samples were collected from the dorsal artery of foot for deter mination of the levels of blood glucose,plasma cortisone,epinephrine and norepinephrine.Results Compared with group C,the agitation score,incidence of agitation,VAS score,and incidence of postoperative hypertension were significantly decreased in R,D and RD groups,especially in R and D groups.The time for recovery from anesthesia and time for extubation were significantly shorter in R and RD groups than in group C.Ramsay sedation scores were significantly higher at the onset of extubation in R,D and RD groups than in group C.Ramsay sedation scores were significantly higher in D and RD groups than in group R.Compared with group C,the levels of blood glucose,plasma cortisone,epinephrine and norepinephrine were significantly decreased in R,D and RD groups,especially in group RD.Conclusion Ropivacaine infiltration combined with dezocine can reduce the agitation during recovery from general anesthesia in the patients undergoing cerebral surgery.

Glucagon like peptide-1 increases visfatin expression in 3T3-L1 adipocytes via PKA pathway / 中华内分泌代谢杂志

Objective To test whether glucagon like peptide-1 (GLP-1) would regulate the expression of visfatin in adipocytes,and to explore the mechanism of this effect.Methods Fully differentiated 3T3-L1 adipocytes were treated with GLP-1.Total RNA was extracted for analyzing the level of visfatin mRNA by quantitative RT-PCR.The media were collected for measuring the level of visfatin protein by enzyme linked immuno-assay (ELISA).In order to test the involvement of PKA pathway,the adipocytes were pretreated with a specific pharmacological PKA inhibitor H89 for 30 min before GLP-1 was added.Results GLP-1 increased visfatin expression in a time-and dose-dependent manner.The level of visfatin significantly increased at the concentration of 10 10 mol/L GLP-1 (P＜0.05),and reached the peak at 10-9 mol/L (P＜0.01).After incubation for 18 hours,GLP-1 dominantly increased the level of visfatin (P＜0.05).Inhibition of PKA pathway by H89 partially blocked the effect of GLP-1 on visfatin expression.Conclusions GLP-1 may enhance the expression of visfatin in 3T3-L1 adipocyte via the PKA pathway,which might contribute to the improvement in glucose homeostasis.

Effects of different collagenase digestion on yield rate of purified islets in rats / 中华器官移植杂志

ObjectiveTo compare the yield rate of rats islets between different collagenase digestion groups.MethodsThe SD rats were randomly divided into two groups as following by using random digits table:collagenase P group (pancreas digested by 1 mg/ml collagenase P) and type Ⅴ collagenase group (pancreas digested by 1 mg/ml type Ⅴ collagenase).After pancreas digestion,rat islet cells in two groups were culture,purified and stained with DTZ.The mean islet number and islet equivalent (IEQ) before and after purification were measured under an inverted microscope.The viability of purified islets was assessed by fluorescence staining of aridine orange (AO) and propidium iodide (PI) under the fluorescence microscopy.After purification and culture for two days,islets function was evaluated by insulin releasing tests in the two groups.ResultsBefore purification,there was no significant difference in the islets number obtained from the pancreas between two groups (P＞0.05),but there was significant difference in the IEQ (P＜0.05).After purification,the islets number in type Ⅴcollagenase group and collagenase P group was (485 ± 113)/pancrease and (643 ± 82)/pancrease,and IEQ was (674 ± 157)/pancreas and (989 ± 126)/pancreas,respectively (P＜0.05).Islet viability in type Ⅴcollagenase group and collagenase P group was (96.13 ±1.13) ％ and (96.38 ± 0.92) ％ respectively (P＞0.05).The results of insulin releasing tests revealed there was no significant difference in islet function stimulated by hypoglycemia and hyperglycemia between two groups (P＞0.05).ConclusionTwo types of collagenase are suitable for the islets digestion in rats.The stability of digestion and yield rate of purified islets in collagenase P group are higher than in type Ⅴ collagenase group.

Clinical study on the relationship between the activation of the IKK-IκB-NFκB pathway and insulin resistance / 中华内分泌代谢杂志

Objective To explore the difference involved in the activation of inflammation pathway and the plasma level of inflammatory factors in the subjects with different sorts of insulin sensitivity. Methods The study was carried out in 38 women, consisting of obesity (n = 22 ) and control (n = 16 ) groups according to body mass index. The insulin sensitivity was assessed by homeostasis model assessment of insulin resistance (HOMAIR). Plasma concentrations of interleukin-6 (II-6) and IL-1β were determined by enzyme immunoassay. Western blot analysis was used to examine total protein expression and phosphorylation levels of IκB kinase (IKK) ,inhibitor of nuclear factor-κB ( IκB ) in peripheral blood leukcocytes. Electrophoretic mobility shift assay (EMSA)was used to detect the binding activity of NFκB. Results The levels of fasting plasma insulin[62.2 ( 20.0-127. 0) pmol/L vs 19. 15 ( 14. 2-47. 8 ) pmol/L, P<0. 01], HOMA-IR[2. 32 ( 0. 76-5.49 ) vs 0.70(0.53-1.7),P<0.0l], HbA1 C[(5.42±0. 45 ) % vs ( 5.08 ±0. 38) %, P<0. 05], triglyceride[( 1.75 ±0. 68 vs 1.22 ±0. 58 )mmol/L, P<0. 05], plasma IL-6[3. 15 (0. 03-22. 2) pg/ml vs 1.26 (0. 74-6.06 ) pg/ml, P<0. 01], and IL-1 β[6. 53 ( 0. 84-36 ) pg/ml vs 3. 16( 1.48-8. 86 ) pg/ml, P<0. 01]in obesity group were significantly higher than those in control group. Compared with control group, the levels of IKKo, IKKβ expression and IκBα serine phosphorylation in obesity group were markedly increased, while the expression of IκBα was significantly reduced. Accompanied with the degradation of IκBα protein, the binding activity of NFκB in obesity group was significantly increased. Conclusions The plasma levels of IL-6 and IL-1β were significantly raised in obesity group. The activation of IKK-IκB-NFκB pathway is closely associated with the genesis and development of insulin resistance in obese subjects.

Visfatin inhibits pancreatic β-cell line MIN6 apoptosis via PI3K-Akt and MAPK-ERK1/2 signaling pathways / 中华内分泌代谢杂志

To investigate the effects and the mechanism of visfatin on MIN6 cell signaling pathway and apoptosis induced by palmitate.Human recombinant visfatin promotes protein kinase B (Akt) and extracellularsignal regulating kinase (ERK)1/2 phosphorylation in dose-and time-dependent manner,and prevents MIN6 cell from apoptosis induced by palmitate (P<0.05 or P<0.01).The activation of Akt and ERK1/2 signaling pathway may be one of the molecular mechanisms of visfatin.

α-lipoic acid inhibits the effects of Iκβ kinase β on islet / 中华内分泌代谢杂志

Objective To investigate the effects of differentiated 3T3-L1 adipoeytes on inflammation of rat islet cells,as well as the protective effect of a-lipoic acid on the inflammation in vitro.Methotis Rat islet cells were divided into three groups:the control group,the experimental co-culture system group(cocuhured with differentiated mature 3T3-LI adipoeytes)and the intervention group (cocuhured with mature 3T3-LI adipocytes containing 4 μg/ml a-lipoic acid).Insulin releasing lest wag performed for estinmting the function of islet cells in culture supernatant of difierent groups.At the same time,the expression level of IKKIβin islet cells Was detected by western blot and realtime PCR.Results There was significant decrease of insulin stimulation index (SI) in experimental co-culture system group compared with the control group and intervention group(1.0 ±0.1 vs 2.6±0.2,2.5±0.5 respectively;P<0.01),while,the mRNA(4.62±0.60 vs1.00±0.46 and 2.25±0.75;P<0.01)and protein expression of IKKβ were significandy increased in the experimental group as compared with the other two groups.Conclusions In the co-culture system of adipocytes/islet cells,impaired function of islet cells could be induced by IKKβ activation,IKKβ Was a key molecule in inflamnmtion signal pathway in islet cells and could be activated by 3T3-LI adipocytes.a-lipoic acid Was able to reverse the impaired function of islet cells by suppressing IKKβ expression.

Expression of visfatin in MIN6 islet IS-cells and effects of glucose and palmitate / 中华内分泌代谢杂志

Visfatin was expressed in rat anti mouse islets,as well as in MIN6 cells. The visfatin expression was affected by various concentrations of environmental glucose (5.5 and 33.3 mmoL/L) and palmitate(0.5 mmol/L). As compared with low-level glucose medium (5.5 mmol/L, 1.0±0.11) , visfatin expression increased in media with high glucose and palmitate (1.32 ±0. 18, 1. 33±0. 15,1.72±0.27, all P<0. 05). The result suggests that visfatin seems to be involved in the regulation of insulin secretion.

Influence of ketamine anesthesia on the pathological outcome of focal cerebral ischemia model in rats / 中国组织工程研究

BACKGROUND: Focal cerebral ischemia model in rats should be established under drugged state by surgery operation, but anaesthetic drug may influence the outcome of focal cerebral ischemia.OBJECTIVE: To observe the effects of ketamine anesthesia on the pathological outcome of focal cerebral ischemia model in rats, and perform control with pentobarbital.DESIGN: Randomized controlled animal experiment.SETTING: Center of Experimental Animal and Department of Pathology of Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University.MATERIALS: The experiment was performed in the Center of Experimental Animal and Department of Pathology of Second Affiliated Hospital,School of Medicine, Xi'an Jiaotong University from May 2004 to March 2005. Thirty male SD rats were randomly assigned into pentobarbital group and ketamine group with 15 rats in each group.METHODS: The rats in the pentobarbital group and ketamine group were subjected to 40 mg/kg pentobarbital and 60 mg/kg ketamine by abdominal anaesthesia, respectively. The permanent middle cerebral artery occlusion (MCAO) was performed in rats by thread embolism in cavity in order to induce cerebral ischemia after abolition of righting reflex.MAIN OUTCOME MEASURES: ①A modified Bederson's scoring system was adopted to determine the neurological functional deficit at hour 4 after the MCAO. ②Five rats from each group were selected at hour 24 after MCAO. They were killed and their brain was stained with 20 g/L 2,-3,-5-triphenyltetrazolium hydrochloride (TTC). The infarct volume was determined. ③ MCAO was performed for 72 hours and mortality rate of two groups were recorded. Four rats in each group were re-anesthetized. They were killed and their brain was gained. Survival neurons were detected with toluidine blue staining.RESULTS: Totally 30 rats were involved in the result analysis. ①There was no significant difference in neurological score 4 hours after MCAO between pentobarbital group and ketamine group (1.46±0.98,1.38±0.68 ,P＞0.05). ②The infarct volume in the ketamine group was less than that in the pentobarbital group at hour 24 after MCAO [(28.1±4.11)%,37.8±4.95]%, P＜0.05]. ③The mortality rate 72 hours after ischemia was not significantly different between pentobarbital group and ketamine group (42% vs 33%,P＞0.05). But neuron density in penumbra in the ketamine group was higher than that in the pentobarbital group [(836±15),(740±24) numbers/mm2, P＜0.05].CONCLUSION: ①The ketamine anesthesia induces minor brain injury in setting of the focal cerebral ischemia model in rats. ②When neuroprotective effects of procedures or drugs being studied are evaluated in this focal cerebral ischemia model, they might provide no additional advantage to cerebral ischemia.

Effects of ketamine on the expression of N-methyl-D-aspartate receptor-1 in a rat model of focal cerebral ischemia / 中华麻醉学杂志

Objective To investigate the effects of ketamine on the expression of NMDA receptor-1(NRⅠ)in a rat model of focal cerebral ischemia and the possible mechanism of the neuroprotection.Methods Forty healthy male SD rats weighing 250-290g were randomly divided into 2 group(n=20 each):groupⅠketamine and groupⅡpentobarbital.The aminals were anesthetized with intraperitoneal ketamine 60 mg?kg~(-1) in groupⅠor pentobarbital 40 mg?kg~(-1) in groupⅡ.Focal cerebral ischemia was produced by permanent middle cerebral artery occludion(MCAO).The animals were killed at 24 h and 72 h of MCAO and their brains removed for determination of infarct size,the number of living neurons in the penumbra and the expression of NRⅠprotein(immuno- histochemistry).Results The infarct size was significantly smaller;the number of living neurons in penumbra significantly larger and NRⅠexpression significantly down-regulated in ketamine group than in pentobarbital group.Conclusion Ketamine can protect the brain against ischemia through downregulation of NMDA receptor-1.