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Action mechanisms of a new erythrocyte-derived depressing factor

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Chinese Science Bulletin 2000年第23期45卷 2113-2118页

作者： Yunyi Wen Xiaochun Zhang Xiaorong Xu Guiqing Zhao Fang Wan Peking Union med coll Inst Basic Med Sci Dept Physiol Sch Basic MedChinese Acad Med Sci Beijing 100005 Peoples R China

To investigate the action mechanisms of a new erythrocyte-derived depressing factor(EDDF), the focus is placed on the effect of EDDF on both cytosolic and nuclear free calcium (Ca2+) transportation in vascular smooth muscle cell (VSMC), as well as the apoptosis and cell cycle of VSMC of rats. EDDF has been extracted from human erythrocytes. The changes of Ca2+ levels in cytoplasm ([Ca2+],) and nucleus ([Ca2+]n) have been observed using a laser scanning confocal microscope together with fluo-3/AM as a calcium indicator. Flow cytometric technique was used to study the effect of EDDF on cell cycle and apoptosis of VSMC. [Ca2+]j and [Ca2+]n were significantly decreased through several different pathways: ( i) it reduced the Ca2+ influx by blocking L-type voltage-dependent calcium channel (L-VDC) and R-type voltage-dependent calcium channel (R-VDC); (ii) it inhibited the Ca2+ release from inositol 1, 4, 5-trisphosphate (IP3) sensitive calcium store; and (iii) activated Ca2+-ATPase of sarcoplasmic reticulum (

关键词： erythrocyte-derived depressing factor (EDDF) calcium transportation cell cycle apoptosis vascular smooth muscle ceil.

Actions of genistein on contractile response of smooth muscle isolated from guinea pig gallbladder

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Hepatobiliary & Pancreatic Diseases International 2009年第6期8卷 614-619页

作者： Luo, Ya-Li Wang, Ya-Li Li, Neng-Lian Zheng, Tian-Zhen Zhang, Li She, Ya-Li Hu, Shu-Ming Gansu coll Tradit Chinese med Dept Pathol Dept Basic Med Lanzhou 730000 Peoples R China Lanzhou Univ Dept Physiol Coll Basic Med Lanzhou 730000 Peoples R China

BACKGROUND: Defective contractile motility of the gallbladder is an important factor for gallstone formation. Estrogen might increase the risk of gallstones and cholecystitis, and estradiol inhibits the contractile activity of isolated strips of guinea pig gallbladder. The potential risks associated with hormone replacement therapy (HRT) include symptomatic gallstones. Phytoestrogen have been used to treat menopause syndromes by replacing traditional estrogen. This experiment aimed to determine the effects of the phytoestrogen genistein on the contractile response of smooth muscle strips isolated from guinea pig gallbladder and its possible mechanism of action. METHODS: Guinea pigs were sacrificed to remove the whole gallbladder. Two or three smooth muscle strips were cut longitudinally. Each strip was suspended in a tissue chamber containing Krebs solution. After 2 hours of equilibration, contractile response indexes were recorded. Different concentrations of genistein were added to the chamber and the contractile responses were measured. Each antagonist was added 2 minutes before genistein to study possible mechanisms. The effect of genistein on calcium-dependent contraction curves and biphasic contraction in calcium-free Krebs solution were measured. RESULTS: Genistein decreased the resting tension dose-dependently, and reduced the mean contractile amplitude and frequency in gallbladder strips. Ranitidine partly inhibited the effect of genistein, but methylene blue, N(omega)-nitro-L-arginine, and propranolol hydrochloride did not influence this action. Genistein had no significant effects on calcium-dependent contraction. Genistein reduced the first contraction induced by acetylcholine chloride, but did not affect the second contraction caused by CaCl(2). CONCLUSIONS: Genistein relaxed smooth muscle isolated from the gallbladder of guinea pigs and this might contribute to the formation of gallstones. The inhibitory action might be related to H(2) receptors and th

关键词： genistein isolated gallbladder smooth muscle calcium channel H(2) receptor guinea pigs

Protective role of a novel human erythrocyte-derived depressing factor on blood vessels in rats

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Chinese Science Bulletin 2002年第9期47卷 717-721页

作者： Huan Pang Yunyi Wen Lei Shi Ning Ma Yutang Wang Chinese Acad med Sci Inst Basic Med Sci Dept Physiol Sch Basic MedPeking Union Med Coll Beijing 100005 Peoples R China

The protective role of a human erythro-cyte-derived depressing factor (EDDF) on blood vessels was evaluated. The experiments were carried out on 25 male Wistar rats aged 6-8 weeks, which were divided into control (n=8), calcium overload (n=8) and NG-L-nitro-arginine hypertensive model groups (L-NNA, n = 9), respectively. The isolated vascular ring perfusion assay, two-photon laser scanning fluorescence microscopy (TPM) and transmitted electron microscope were used to examine the effect of EDDF on vascular function and ultrastructure. Results showed that the contractile response of calcium overload rats and L-NNA rats to phenylephrine (PE) was significantly enhanced compared with that of the control (P < 0.05), and EDDF (10-3g·mL-1) remarkably decreased the vascular contractile response of control’s and calcium overload rats (P < 0.05), while EDDF had no effect on that of L-NNA rats. EDDF also alleviated the ultrastructural lesion of aorta VSMC in calcium overload rats by easing the abnormal in the

关键词： erythrocyte-derived depressing factor calcium over-load NG-L-nitro-arginine vascular ring two-photon laser scan-ning fluorescence microscope ultrostructure.

Meridian-like character of reflex electromyogram activity in longissimus dorsi muscles

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Chinese Science Bulletin 2001年第1期46卷 57-62页

作者： Chao Ma Zheng Zheng Yikuan Xie Chinese Acad med Sci Peking Union Med Coll Inst Basic Med Sci Beijing 100005 Peoples R China

We studied the temporal and spacial character of the electromyogram (EMG) evoked by acupuncture in long-issimus dorsi (LD) muscles of rat, and evaluated the effect of needling direction or local blockade on EMG propagation. When certain sites on LD muscle were acupunctured, asynchronous EMG could be activated not only at the acupunctured point, but also within the muscle region supplied by the adjacent 2-3 vertebral segments. The EMG evoked by stimulation on the borderline of aponeurosis and muscle venter was larger in amplitude than those on the other sites in the same vertebral segment. When the distance from the recorded site to stimulated site increased, the EMG amplitude decreased, and its latency prolonged. Acupuncture in an oblique direction toward rostral or caudal side of the muscle enhanced the EMG amplitude in the same direction. EMG activity was weakened and its propagation was blocked by local injection of procaine. These results indicated that the character of EMG propagation evoked by

关键词： longissimus dorsi muscle reflex electromyogram activity acupuncture needle-feeling propagation.

Cloning and identification of a novel human glioma differentiation related gene GDR1

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Chinese Science Bulletin 2000年第11期45卷 995-999页

作者： Guangtao Li Hulin Jin Songnian Hu Jian Jin Chun Tu Jiangang Yuan Boqin Qiang Peking Union med coll Sch Basic MedNatl Ctr Human Genome Res Chinese Acad Med Sci Inst Basic Med SciNatl Lab Med Mol Biol Beijing 100005 Peoples R China

In order to identify the genes associated with glioblastoma differentiation, some ESTs, expressed differentially in the control cell and the differentiated human glioblastoma cell line BT-325 induced by the all-trans retinoid acid, have been isolated by the method of DDRT-PCR. Of the 46 ESTs sequenced, 19 are from new genes. A full-length 1 535-bp cDNA, termed gene GDR1, has been isolated from the human cDNA library using the probe designed according to one of the novel ESTs, HGBB098. The open reading frame of GDR1 gene encodes a putative protein containing 334 amino acid residues. Blast against the current GenBank DMA and protein sequence database did not reveal significant homology with any known proteins. RT-PCR shows that GDR1 mRNA level increased in the differentiated BT-325 cells after being treated with RA. The different expression patterns of GDR1 mRNA in human tissues have been detected through the multiple tissue Northern blot hybridization.

关键词： human glioma GDR1 RT-PCR.

Effects and mechanisms of three kinds of chemical inducers on the expression of rat GST-P gene

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Chinese Science Bulletin 2000年第8期45卷 725-729页

作者： Mingxiang Liao Dongyuan Liu Jin Zuo Hongyun Zhang Fude Fang Chinese Acad med Sci Peking Union Med Coll Inst Basic Med Sci Natl Lab Med Mol Biol Beijing 100005 Peoples R China

The expression of rat Glutathione S-transferase P (GST-P) gene can be induced by many kinds of chemical inducers. We have studied the mechanisms of the expression of GST-P gene induced by 3 kinds of Chemical inducers using the induction of the gene expression by chemical inducers, transient transfection, reporter gene assays, electrophoretic mobility shift assays (EMSA) and Northern blot analysis. The results indicate that the effects and mechanisms of chemical inducers on the expression of GS7'-Pgene are different. The interaction of AP-1 or other corresponding transcription factors activated by phorbol ester (TPA) or glycidyl methatylate (GMA) and GPEl enhancer element induces the expression of GST-P gene, while some unknown factors activated by H2O2 interact with GPEII enhancer element.

关键词： glutathione S-transferase P chemical inducers control of gene expression.

Effects of electroacupuncture on microcirculatory blood flow and glucose transporter function in the hippocampus

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Neural Regeneration Research 2011年第3期6卷 200-205页

作者： Lu, Yan Han, Bingbing Wang, Shijun Shandong Univ Tradit Chinese med Dept Expt Acupuncturol Acupuncture & Moxibust Coll Jinan 250355 Shandong Peoples R China Shandong Univ Tradit Chinese med Microcirculat Lab Basic Med Coll Jinan 250355 Shandong Peoples R China

Nerve cell metabolism in post brain ischemia depends on increased microcirculation perfusion and transport function of microvascular endothelial cells. In the present study, a rat model of middle cerebral artery occlusion was established to investigate the influence of electroacupuncture （EA） on hippocampal CA1 cerebral blood flow and glucose transporter 1 （GLUT1） expression in the microvascular endothelial cells. Following EA at Neiguan （PC 6）, the cerebral blood flow in the ischemic hippocampal CA1 region was significantly elevated, the number and microvascular integrated absorbance of the GLUTl-positive cells were significantly increased, nerve cell damage was ameliorated, and GLUT1 protein expression in the ischemic hippocampus was significantly increased. Results demonstrate that EA increased the cerebral blood flow of the hippocampal CA1 region and improved the glucose transport function, thereby attenuating neuronal injuries.

关键词： Electroacupuncture Neiguan (PC 6) focal cerebral ischemia microvascularendothelial cells glucose transporter 1 cerebral blood flow CA1 region neural regeneration

Establishment of Jurkat tet-on cell line

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Chinese Science Bulletin 2000年第6期45卷 532-536页

作者： Hongwei Wang Jing Zhang Ninghua Wu Yufei Shen Peking Union med coll Chinese Acad Med Sci State Key Lab Med Mol Biol Inst Basic Med Sci Beijing 100005 Peoples R China

Tet-control system is developed to tightly control target gene expression in mammalian cells by using the regulatory elements of tetracycline-repressor of the transposor Tn10from E. coli. We have transfected reverse tetracycline-controlled transactivator gene (rtTA) into genome of Jurkat cells and established two Jurkat tet-on celi lines. Induction of luciferase reporter activity with doxycycline, a tetracycline derivative, is dose-dependent with a peak value of 32-fold increment. Establishment of Jurkat tet-on cell lines greatly facilitates guantitative studies on target gene functions in the cells.

关键词： tet-on cell line Jurkat cell tetracycline control system.

Expression of neurofilament gene in spinal motoneurons during neural regeneration

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Chinese Science Bulletin 1999年第3期44卷 225-229页

作者： Ruifa Mi Xiangqun Shi Shuhong Liu Changman Zhou Jiazheng Wang Ming Fan Acad Mil med Sci Inst Basic Med Sci Beijing 100850 Peoples R China Beijing med coll PLA Beijing 100071 Peoples R China

The technique in situ hybridization was used to measure the levels of light （NF-L）,medium（NF-M） and heavy （NF-H） neurofilament protein subunits mRNA in L4-6 spinal motoneurons in adult rat during regeneration following a unilateral crush of the sciatic *** was found that the hybridization signals of each neurofilament subunit mRNA were dramatically decreased in spinal motoneurons postaxotomy by light microscopy. The hybridization signals of NF-L and NF-M mRNA were located in cytoplasm of neurons, whereas NF-H mRNA was found in both nucleus and cytoplasm of neurons. lmage analysis showed that the encoding levels of mRNA for each of neurofilament subunit mRNA reduced on the 3rd d and returned to control levels on the 28th d following the lesion. The relative levels of mRNA coding for each neurofilament subunit were significantly different. The lowest level of NF-L mRNA was observed at 5 d postaxotomy, and that of NF-M, NF-H mRNA on the 7th and 10th d after injury. Moreover,the levels of HF-M and

关键词： neurofilament mRNA neural regeneration spinal motoneurons in situ hybridization rat.