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Er-Qing Wei

Publications and source records attributed to Er-Qing Wei.

At least 37 records · Page 2Linked to original sources
PubMed2005

Protective effects of baicalin on oxygen/glucose deprivation- and NMDA-induced injuries in rat hippocampal slices.

Baicalin is a flavonoid derivative from Scutellaria baicalensis Georgi with various pharmacological effects. Recently, the neuroprotective effect of baicalin was reported. To confirm this effect and explore the possible mechanism, we have investigated the protective effect of baicalin on ischaemiclike or excitotoxic injury and the activation of protein kinase C alpha (PKC(alpha)) in rat hippocampal slices. In-vitro ischaemic-like injury was induced by oxygen/glucose deprivation (OGD) and the excitotoxic injury by N-methyl-D-aspartate (NMDA). The viability and swelling of the slices were detected by triphenyltetrazolium chloride (TTC) staining and image analysis of light transmittance (LT), respectively. The translocation of PKC(alpha) was measured by immunoblotting. Baicalin was added during both injuries. Baicalin (0.1, 1, and 10 micromol L(-1)) concentration-dependently inhibited OGD-induced viability reduction and acute neuron swelling, and inhibited the increased portion of PKC(alpha) present in the membrane fraction over the total PKC(alpha). Baicalin ameliorated NMDA-induced viability reduction (not LT elevation) and inhibited the NMDA-increased membrane portion of PKC(alpha) at 1 micromol L(-1). We concluded that baicalin had a protective effect on ischaemic-like or excitotoxic injury in rat hippocampal slices, which might have been partly related to inhibition of PKC(alpha) translocation.

Animals↗
PubMed2004

Minocycline protects PC12 cells from ischemic-like injury and inhibits 5-lipoxygenase activation.

Minocycline protects animals against cerebral ischemia by inhibiting inflammation. To determine whether minocycline protects PC12 cells from in vitro ischemic-like injury and affects pro-inflammatory 5-lipoxygenase activation, the cell viability and 5-lipoxygenase translocation to nuclear membrane were observed after oxygen-glucose deprivation (OGD). We found that OGD reduced cell viability, which was attenuated by minocycline and 5-lipoxygenase inhibitor caffeic acid. 5-Lipoxygenase protein was detected in PC12 cells by immunohistochemical and Western blot analyses. OGD induced 5-lipoxygenase translocation to nuclear membranes, which was abolished by minocycline and caffeic acid. Thus, minocycline can protect PC12 cells from in vitro ischemic-like injury, and this effect may be partly related to the inhibition of 5-lipoxygenase activation.

Animals↗
PubMed2004

Montelukast, a cysteinyl leukotriene receptor-1 antagonist, dose- and time-dependently protects against focal cerebral ischemia in mice.

Our previous studies showed that cysteinyl leukotriene receptor-1 (CysLT1) antagonist pranlukast has a neuroprotective effect on cerebral ischemia in rats and mice. However, whether the neuroprotective effect of pranlukast is its special action or a common action of CysLT1 receptor antagonists remains to be clarified. This study was performed to determine whether montelukast, another CysLT1 receptor antagonist, has the neuroprotective effect on focal cerebral ischemia in mice, and to observe its dose- and time-dependent properties. Permanent focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). Montelukast was injected intraperitoneally either as multiple doses (once a day for 3 days and 30 min before MCAO) or as a single dose (at 30 min before, 30 min after, or 1 h after MCAO), respectively, and pranlukast and edaravone were used as controls. The neurological deficits, infarct volumes, brain edema, neuron density, and Evans blue extravasation in the brain were determined 24 h after MCAO. Pretreatments with multiple doses or a single dose of montelukast (0.1 and 1.0 mg/kg) before MCAO significantly attenuated all the ischemic insults. Post-treatment with a single dose of montelukast (0.1 and 1.0 mg/kg) at 30 min after MCAO also significantly decreased brain edema and infarct volume, but not neurological deficits. However, post-treatment with a single dose of montelukast at 1 h after MCAO had no significant effect. Pranlukast showed the same effects as montelukast, but edaravone attenuated the ischemic insults only with multiple doses before MCAO. Thus, montelukast has a dose- and time-dependent neuroprotective effect on permanent focal cerebral ischemia in mice, with an effective dose range of 0.1-1.0 mg/kg and a therapeutic window of 30 min. These findings further support the therapeutic potential of CysLT1 receptor antagonists in the treatment of cerebral ischemia at earlier phases.

Acetates↗
PubMed2004

Expression of cysteinyl leukotriene receptor 1 in human traumatic brain injury and brain tumors.

Cysteinyl leukotrienes (CysLTs) are potent proinflammatory mediators. CysLT receptor 1 (CysLT(1)) is one of the two CysLT receptors that has been cloned. Although the expression of CysLT(1) in the brain has been demonstrated by Northern blot and RT-PCR analyses, the location of CysLT(1) in the brain remains unknown. The objective of this study was to examine the distribution of CysLT(1) by immunohistochemical analysis in human brains with traumatic injury or tumors. CysLT(1) was expressed intensely in the microvascular endothelial cells in both normal and abnormal conditions. At 8 days after traumatic injury, microvascular regeneration was found and all of the endothelial cells highly expressed CysLT(1). In gray and white matters of the normal regions of the brain, CysLT(1) was expressed weekly or not at all. However, the CysLT(1) expression increased in the neuron- and glial-appearing cells in gray and white matters after traumatic brain injury. CysLT(1) was also detected in astrocytoma, ganglioglioma and metastatic adenocarcinoma, and the expression in the neuron- and glial-appearing cells around brain tumors increased robustly.

Adult↗
PubMed2004

Monosialoganglioside protected ischemic rat hippocampal slices through stabilizing expression of N-methyl-D-aspartate receptor subunit.

AIM: To determine direct protective effect of monosialoganglioside (GM1) on hippocampal slices after oxygen-glucose deprivation and reperfusion (OGD/RP), and investigate the influence on the expression of N-methyl-D-aspartate receptor subunit 1 (NMDAR1) in those hippocampal slices. METHODS: Injury of hippocampal slices and protective effects of GM1 were detected by 2,3,5-triphenyltetrazolium chloride (TTC) staining, toluidine blue staining, and transmission electron microscopy of rat hippocampal slices. Expression of NMDAR1 was detected by Western blot. RESULTS: (1) GM1 at 1.0 micromol/L was the most effective concentration to preserve the TTC staining of the hippocampal slices after OGD/RP (P<0.05), and the next was GM1 at 10.0 micromol/L (P<0.05). (2) Toluidine blue staining and transmission electron microscopy showed GM1 protected the injuried hippocamal slices after OGD/RP. (3) GM1 downregulated the temporally high expression of NMDAR1 in the hippocampal slices immediately after a 25-min OGD and prevented the over low expression of NMDAR1 after a 30-min reperfusion. CONCLUSION: GM1 could protect injuried rat hippocampal slices after OGD/RP through stabilizing the expression of NMDAR1.

Animals↗
PubMed2004

Montelukast modulates lung CysLT(1) receptor expression and eosinophilic inflammation in asthmatic mice.

AIM: To determine the expressions of cysteinyl leukotriene receptors, CysLT1 and CysLT2, in airway eosinophilic inflammation of OVA-induced asthmatic mice and the modulation by montelukast, a CysLT1 receptor antagonist. METHODS: Asthma model was induced by chronic exposure to ovalbumin (OVA) in C57BL/6 mice. The eosinophils in bronchoalveolar lavage (BAL) fluid and lung tissues were counted, IL-5 level in BAL fluid was measured, and CysLT1 and CysLT2 receptor mRNA expressions were detected by semi-quantitative RT-PCR. RESULTS: Montelukast (6 mg/kg, once per day for 20 d) significantly suppressed the increased eosinophils in BAL fluid and lung tissue, and increased IL-5 level in BAL fluid in OVA challenged mice. OVA challenge increased CysLT1 but decreased CysLT2 receptor mRNA expression. Montelukast inhibited the increased CysLT1 but not the reduced CysLT2 expression after OVA challenge. CONCLUSION: CysLT receptors are modulated immunologically, and montelukast inhibits up-regulation of CysLT1 receptor and airway eosinophilic inflammation in asthmatic mice.

Acetates↗
PubMed2004

[Investigation on emerging rate and prevalence of male homosexuality in Hangzhou City].

OBJECTIVE: To understand prevalence of male homosexuality in Hangzhou, Zhejiang Provicne of China. METHODS: To investigate emerging rate of male homosexuality and infer its prevalence in public gathering by observation at fixed points and questionnaire survey in gay men. RESULTS: There were 2 012.5 male homosexuals taking part in public gatherings, with 95% confidence interval of 1 899 - 2 129, in Hangzhou. Frequency of such activities they took part in was once every 3 - 15 days (11.3 +/- 2.7) days. Each gay man knew 1.51 +/- 0.33 (0 - 6) other male homosexuals who never exposed their sexual orientation. The emerging number of male homosexuals was 5 051.38. CONCLUSION: The emerging rate of male homosexuality was 0.58%, with its prevalence of about 1% - 2% in public gatherings in Hangzhou.

Adult↗
PubMed2003

[An improved quantitative method for evaluating neurological deficits in mice with focal cerebral ischemia].

The purpose of this study was to develop a quantitative and objective method for evaluating neurological deficits in mice with focal cerebral ischemia. After middle cerebral artery occlusion (MCAO), the neurological deficits were evaluated 24 h later. We measured the mean angles, dominant angles and turns in a hanged test in which the mice were sticked on the wall, and the holding angles in an inclined plane test as well, Then we determined the cerebral infarct volumes, neuron density in hippocampus, cortex and subcortical areas 24 h after MCAO. The correlations among infarct volume, neuron density and neurological deficits were analyzed. We also compared the quantitative method with two typical complex methods of behavioral assessment. The effect of [pranlukast, 4-oxo-8-[p-(4-phenylbutyloxy) benzoylamino]-2-(tetrazol-5-yl)-4H-1-benzopyran hemihydrate] (ONO-1078), a neuroprotective agent, on ischemic injury was observed using this method. We found that the variables measured by both quantitative and typical behavioral methods significantly changed in the ischemic mice, and correlated with the infarct volumes and neuron densities. The quantitative variables well correlated with those of typical behavioral assessment, too. ONO-1078 inhibited ischemic injury and reduced the total scores of quantitative assessment. Thus, the quantitative method we developed is useful in evaluating neurological deficits of focal cerebral ischemia with the advantages of objectivity, quantification, simplicity and non-invasion, and can be used in the evaluation of neuroprotective effects of drugs.

Animals↗
PubMed2003

Effects of endogenous histamine on seizure development of pentylenetetrazole-induced kindling in rats.

This study was performed to investigate whether or not endogenous histamine can protect seizure development of pentylenetetrazole (PTZ)-induced kindling in rats. An intracerebroventricular (i.c.v.) injection with clobenpropit (5 and 10 microg), a representative H(3)-antagonist, significantly prolonged the onset of kindling and inhibited the seizure stages in a dose-dependent manner. Its action was significantly reversed by both immepip (2 microg, i.c.v.), an H(3)-agonist, and alpha-fluoromethylhistidine (alpha-FMH, 10 microg, i.c.v.), a selective histidine decarboxylase inhibitor. alpha-FMH (20 microg, i.c.v.) and pyrilamine (1 and 5 mg/kg i.p.), a classical H(1)-antagonist, markedly augmented the severity of seizure development of PTZ-induced kindling. Therefore, these results indicate that brain endogenous histamine plays a certain protective role on seizure development of PTZ-induced kindling in rats, and that its protective roles are mediated by H(1)-receptors.

Animals↗
PubMed2003

Neuroprotective effect of ONO-1078, a leukotriene receptor antagonist, on transient global cerebral ischemia in rats.

AIM: To determine whether ONO-1078 [pranlukast, 4-oxo-8-[p-(4-phenylbutyloxy)benzoyl-amono]-2-(tetrazol-5-yl)-4H-1-benzopyran hemihydrate], a potent leukotriene receptor antagonist, possesses a neuroprotective effect on global cerebral ischemia in rats, and to explore its possible mechanism of action. METHODS: Transient global cerebral ischemia was induced by four-vessel occlusion for 10 min and followed by 72-h reperfusion. ONO-1078 (0.03-0.3 mg/kg) and edaravone (MCI-186, 3-methyl-1-phenyl-2-pyrazolin-5-one, a neuroprotective agent) 10 mg/kg were ip injected 30 min before ischemia and 1 h after reperfusion, and once a day afterward. Neurological outcome was evaluated before ischemia and 24, 48, 72 h after reperfusion. Neuron density, the expressions of N-methyl-D-aspartate (NMDA) receptor subunit proteins (NR1, NR2A, NA2B) and vascular cell adhesion molecule 1 (VCAM-1) in the cerebral cortex and hippocampus were measured at 72 h after reperfusion. RESULTS: ONO-1078 (0.1, 0.3 mg/kg) and edaravone (10 mg/kg) improved ischemia-induced neurological deficiency and reduced neuron death. ONO-1078 (0.1, 0.3 mg/kg) significantly inhibited the enhanced expression of NMDA receptor subunit protein NR2A in the cortex and VCAM-1 in the hippocampus of ischemic rats. CONCLUSION: ONO-1078 possesses a neuroprotective effect on global cerebral ischemia in rats, and its mechanism may be partly related to the inhibition of the upregulation of NR2A and VCAM-1 in different regions of the brain.

Animals↗
PubMed2003

Facilitating effect of histamine on spatial memory deficits induced by dizocilpine as evaluated by 8-arm radial maze in SD rats.

AIM: To investigate whether or not histamine is involved in spatial memory deficits induced by dizocilpine (MK-801) as evaluated by 8-arm radial maze of rats. METHODS: 8-Arm (4-arm baited) radial maze was used to measure spatial memory in rats. RESULTS: Bilaterally intrahippocampal (ih) injection of MK-801 (0.3 microg/site) impaired working memory and reference memory in rats. Both histamine (50, 100 ng/site, ih) and intraperitoneal (ip) injection of histidine (100, 200 mg/kg) markedly improved the spatial memory deficits induced by MK-801. On the other hand, the ameliorating effect of histidine (100 mg/kg, ip) was completely antagonized by alpha-fluoromethylhistidine (alpha-FMH, 5 microg/site, ih), a potent and selective histidine decarboxylase (HDC) inhibitor, and H1-antagonist pyrilamine (1 microg/site, ih), but not by H2-antagonist cimetidine, even at a high dose (2.5 microg/site, ih). CONCLUSION: The hippocampal histamine plays an important role in the ameliorating effect on MK-801-induced spatial memory deficits, and its action is mediated through postsynaptic H1-receptor.

Animals↗
PubMed2002

[Novel quantitative method for evaluating oxygen/glucose deprivation-induced injury of hippocampal slices]

OBJECTIVE: To establish a simple, sensitive in vitro method to evaluate oxygen/glucose deprivation (OGD)-induced injury of brain hippocampal slices in rats. METHODS: Rat hippocampal slices were incubated in 2% 2, 3, 5-triphenyltetrazolium chloride (TTC) solution after oxygen/glucose deprivation. They were then soaked in a measured volume of ethanol and dimethylsulfoxide (50:50) to extract the TTC formazan Product which was then measured by spectrophotometry. OGD induced LDH release was simultaneously measured. RESULTS: Progressive prolongation of OGD induced hippocampal injury resulted in decreased formazan coloration as determined by spectrophotometry. There was a parallel increase in LDH release, thus a negative correlation in these two products was noted. (r=-0.933,P <0.01). The injury was attenuated in the brain slices pre-treated with nimodipine, dexamethasone, and ketamine, but not ONO-1078. CONCLUSION: Solvent extraction and spectrophotometric quantification of formazan represents an objective measurement of OGD-induced injury of rat hippocampal slices.

Journal Article↗
PubMed2002

[Light transmission measurement of focal ischemic cerebral infarction in mice]

OBJECTIVE: To evaluate the feasibility of light transmission to measure focal cerebral ischemia in mice. METHODS: Persistent focal cerebral ischemia was induced by middle cerebral artey occlusion (MCAO) in mice. The brain were removed 24 h after MCAO and coronally dissected into 1 mm sections. Using a stereomicroscope, the brain section was illuminated with a halogen lamp and computerized images were stored. Next the brain sections were stained for 30 minutes with 0.5% TTC (2, 3, 5-triphenylterzolim chloride) at 37 degrees C. Using an image analyzer (AnalyPower 1.0), the infarct volumes obtained by light transmittance and TTC staining were calculated. Integrated gray scales of sections of both hemispheres were calculated by Photoshop 5.0. RESULTS: A close correlation existed between cerebral infarct volume measured by light transmission and TTC staining (r=0.81). The mean gray scales measured by both techniques of the ischemic hemispheres as well as those of the cortex, subcortex and hippocampus were siginificantly higher than those of non-ischemic hemispheres and of control mouse hemispheres (P <0.001). Further there were no significant difference between the two hemispheres of control mice and between hemispheres of control mice and non-ischemic hemispheres of the MCAO mice. CONCLUSION: Light transmission can be used for qualitative analysis of focal cerebral ischemia.

Journal Article↗
PubMed2002

[Optical recording method for evaluation of neuronal damage in rat hippocampal slices during ischemia and reperfusion]

OBJECTIVE: To develop a novel technique of optical recording and its validation for assessment of the neuroprotective effect of nimodipine, a L-type calcium channel blocker. METHODS: In vitro ischemia was induced by oxygen/glucose deprivation (OGD), the light transmittance (LT) of rat hippocampal slices undergoing OGD and reperfusion was quantitated using a simple apparatus relying on basic principles of light transmittance and a computerised image analysis system. RESULTS: OGD was associated with increased LT in the stratum radiatum of CA1 area and the dentate gyrus in hippocampal slices. Peak LT occurred (7.59 +/-1.42) min after OGD, followed by a marked decrease in LT (n=15 slices). Nimodipine administration (0.5 &mgr;mol/L, n=10 slices, 5 &mgr;mol/L, n=9 slices) appeared to protect the tissue from OGD damage by inhibiting elevation of LT, However, 50 &mgr;mol/L nimodipine resulted in increased LT (25.83 +/-6.32). min after administration (n=11 slices). CONCLUSION: LT signal measurement is a non-invasive, reliable method for determination of neuronal damage in ischemic rat brain slices Nimodipine is demonstrated opposite neuroprotective effects depending on its dose.

Journal Article↗
PubMed2002

[Effects of TAK-147, a novel acetylcholinesterase inhibitor, on spatial memory deficit as evaluated by Morris water maze of rats]

OBJECTIVE: To evalute the effects of TAK-147, a novel acetylcholinesterase inhibitor on rat spatial memory deficit using the Morris water maze. METHODS: Morris water maze was used to measure spatial memory in rats, and open field test was used to analysis locomotor activity. RESULTS: Scopolamine (0.4mg/kg,IP) significantly increased the latency period in memory acquisition. Intraperitoneal TAK-147 injection ameliorated scopolamine-induced deficit in a dose-related manner. A significant effect was obtained at doses of 0.3 and 1.0 mg/kg. Both TAK-147 (0.3 and 1.0 mg/kg) and tacrine (3 and 5 mg/kg) significantly reversed scopolamine (1.5 mg/kg) increased latency in memory retrieval. However, TAK-147 had a more potent effect than tacrine. In the locomotor test, TAK-147 created no appreciable change, compared with scopolamine or saline. CONCLUSION: A novel acetycholinesterase inhibitor, TAK-147 ameliorates the scopolamine induced impaired spatial memory in rats.

Journal Article↗
PubMed2002

VCAM-1 expression, eosinophil infiltration, and pharmacological modulation in rat allergic airway inflammation.

AIM: To determine vascular cell adhesion molecule-1 (VCAM-1) expression and eosinophil infiltration in the lungs of the rats with allergic airway inflammation, and their possible modulation by dexamethasone and neurokinin-1 receptor antagonist SR140333. METHODS: Sensitized rats were challenged with inhalation of 1 % ovalbumin aerosol. Protein expression of VCAM-1 in the lungs and eosinophil infiltration around bronchi in different groups were determined 24 h after challenge. SR140333 (0.01 and 0.10 mg/kg) and dexamethasone (0.50 mg/kg) were injected ip, twice a day, for 3 d before challenge. RESULTS: The expression of VCAM-1 was increased in the sensitized rat lungs as compared with the non-sensitized rats (P<0.05). The increment was inhibited by pretreatment with dexamethasone (P<0.05), but not with SR140333 (P>0.05). On the other hand, antigen challenge in sensitized rats evoked eosinophil infiltration (P<0.05) but no further increase in VCAM-1 expression (P>0.05). Furthermore, SR140333 inhibited eosinophil infiltration (P<0.05) but had no effect on VCAM-1 expression (P>0.05), whereas dexamethasone inhibited both responses (P<0.05). CONCLUSION: The expression of VCAM-1 increases during antigen sensitization in rat lungs, and dexamethasone and SR140333 may inhibit allergic airway inflammation in different mechanisms.

Animals↗
PubMed2002

Reversal of scopolamine-induced spatial memory deficits in rats by TAK-147.

AIM: To evaluate effect of TAK-147 on spatial memory deficit induced by scopolamine. METHODS: Morris water maze was used to measure spatial memory in rats and open field test was used to analyse locomotor activity. RESULTS: In the acquisition memory process, scopolamine (0.4 mg/kg, ip) markedly increased the escape latency to the platform. Ip injection of both TAK-147 and donepezil ameliorated scopolamine-induced deficit, dose-related and significant effect was obtained at doses of 0.1-1.0 mg/kg. In the memory retrieval process, increased latency induced by scopolamine (1.5 mg/kg, ip) was also significantly reversed by treatment with TAK-147 (0.1, 0.3, and 1.0 mg/kg), donepezil (0.3 and 1.0 mg/kg), and tacrine (3 and 5 mg/kg), respectively. TAK-147 has a little potent efficacy to donepezil, and was more potent than tacrine. In the locomotor test, both TAK-147 and donepizil created no appreciable change of locomotor activities, compared with scopolamine or saline. CONCLUSION: TAK-147 plays an important role in spatial cognition, and this result provides additional evidence that TAK-147 is an ideal AChE inhibitor and is useful for the treatment of Alzheimer's disease.

Animals↗