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Aim To study the protective effects of allicin on acute cerebral ischemia reperfusion injury. Methods The model of cerebral ishemia-3 h/reperfusion-24 h was induced by middle cerebral artery occlusion(MCAO) in SD rats. Allicin(10,20 mg?kg -1) was administered once daily in rats:at 0 h of reperfusion. After 24 h reperfusion, the content of malondialdehyde(MDA),the activities of superoxide dismutase(SOD),GSH and myeloperoxidase(MPO) in brain tissue,the content of NO in plasma were measured. Results Compared with vehicle group, the activity of SOD was increased from 205.87?16.52 to 259.77?19.65 and 284.54?21.79 by allicin 10,20 mg?kg -1; the MDA content was decreased from 38.69?0.10 to 28.68?1.37 and 20.97?0.44 respectively; the GSH content was increased from 28.31?0.64 to 36.19?1.12 and 47.96?0.44 respectively; the NO content was decreased from 29.7?0.49 to 27.38?1.46 and 23.00?0.71 respectively; the MPO content was decreased from 0.29?3.06?10 -2 to 0.26?2.13?10 -2 and 0.23?7.52?10 -2 respectively. Conclusion The protective effects of allicin on acute cerebral ischemia reperfusion injury may be related to increasing antioxidase activities,decreasing lipid peroxidative damage and inhibiting inflammation reaction.
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Aim To investigate the inhibition of cell proliferation and the expression of PCNA gene of human glioma U251 by elemene.Methods Normal control and treatment group with elemene in human glioma U251 were studied, then the inhibition effect was examined by MTT methods and the density of half death was worked out (IC50). The expression of PCNA protein and gene was examined by immunohistochemical method and RT-PCR in different action time or at different concentrations.Results Elemene had a marked antineoplastic effect on glioma U251 with the dependence of dose and time,IC50 was 0.062 g?L-1. Elemene exhibited the expression of PCNA protein and gene,which could be examined by immunohistochemical method and RT-PCR. The expression of PCNA mRNA was lowered with the increase of drug concentration and action time.Conclusion Elemene inhibited the expression of PCAN gene,induced the inhibition of cell proliferation,and had a marked antiproliferative effect on glioma cells.
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Aim To investigate the influence of endostatin on pathological morphology of C_6 glioma and its molecular pharmacologic mechanism.Methods The C_6 cells,the C_6 clone stably transfected with endostatin cDNA(endo-C_6),which the endostatin with biological activities can be secreted from,and the C_6 clone stably transfected with empty vector pBudCE4.1 cDNA(pBud-C_6) were injected subcutaneous in nude mice to establish different tumoral model respectively.The morphologies of these tumoral tissues were observed and compared to each other under light and electron microscope.The expression of VEGF in tumor tissue was determined by ELISA.Results The expression of VEGF in endo-C_6 glioma(endo-C_6G) tissues was lower than that in C_6 glioma(C_6G) and pBud-C_6 glioma(pBud-C_6G).Moreover,endo-C_6G tissue was characteristic of a mimetic envelope,no intratumor bleeding and cystis degeneration,apoptosis of tumor cells,and edema in and around tumor.Rarefied vessels were found in tumor,and no vessel like structure formed by tumor cells was observed.The large irregular necrosis focus was showed in tumor,but mild vascular reaction around necrosis focus and peritumor,rare surrounding invasion.The basal lamina was discontinued.The basemembrane(BM) was loose.Few vesicular vacuolar organelle(VVO) structures were observed in plasma of endothelial cells.In C_6G and pBud-C_6G,tumor lesions demonstrated significant vascular reaction,intratumor bleeding,necrosis,edema in and around tumor,and surrounding infiltration.Vessel like structure formed by tumor cells was also observed.When examined with electron microscope,plenty of VVO structures were observed in plasma of endothelial cells,the worse the edema,the more the VVO were,which coincided with the expression of VEGF.Mostly,loose basal lamina surrounded by small amounts of collagen fibers was multilayer and integrated and continuous.No correlation between gene transfection and fenestra formation or cleft of capillary endothelial cell was observed,no apoptosis of endothelial cells were found.Conclusion In glioma,the apoptosis of endothelial cells tissue was not induced directly by endostatin,but the angiogenesis and vascular reaction can be inhibit by endostatin by down-regulation of the expression of VEGF in C_6 glioma cells.
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Aim To investigate the protective effects and mechanism of aspirin against focal cerebral ischemia-reperfusion in rats. Methods Right middle cerebral artery was occluded by inserting a thread through internal carotid artery for 2 h, and then reperfused for 72 h. 60 mg?kg -1 dose of aspirin was intragastric administrated at 0 h and 6 h after reperfusion. The brain injured area, the mortality, and cerebral edema were estimated. The apoptotic cells of brain tissue were detected by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick-end labeling (TUNEL) method. Bcl-2 and Bax were detected by immunohistochemical staining method. The activity of calcineurin (CaN) in brain tissue was determined by the inorganic phosphorus method. The content of adenosine 5′-triphosphate (ATP) in brain tissue was separated by capillary electrophoresis. Results By using of aspirin 60 mg?kg -1, all indications were dramatically improved. The injured area of brain [from (10.51?1.12)% to (0.94?0.08)%], the cerebral edema of occluded side [from (82.43?2.0)% to (76.29?0.77)%], and the mortality [from 28% to 0%] were dramatically reduced. In brain tissue of occluded side, 60 mg?kg -1 aspirin helped to reduce the number of apoptotic cells from (26.43?2.0) to (17.53?0.44), increase the ratio of Bcl-2/Bax from (0.61?0.05) to (1.01?0.15), inhibit the activity of CaN from (6.03?1.5) to (3.47?0.96), and improve the ATP level from (10.26?1.02) to (25.65?3.45). Conclusion The neuroprotective effects of aspirin on focal cerebral ischemia-reperfusion injury in rats for 72 h might be attributed to its effects by anti-apoptosis, increasing the ratio of Bcl-2/Bax, inhibiting the activity of CaN, and improving the energy metabolism.
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Aim To investigate the protective effect of zileuton,a 5-lipoxygenase inhibitor,on focal cerebral ischemia-reperfusion injury in rats.Methods The right middle cerebral artery of the rat was occluded by inserting a thread through internal carotid artery for 2 h,and then reperfused for 24 h.Zileuton(10,50 mg?kg~(-1)) was orally administered 2 h before ischemia and 0,5,10 h after reperfusion.After 24 h reperfusion,the content of malondialdehyde(MDA) and nitric oxide(NO),the activities of glutathion peroxidase(GSH-PX),myeloperoxidase(MPO) and nitricoxide synthase(NOS) were measured.Results Compared with vehicle group,the infarct size,content of NO and NOS of the brain were significantly reduced in 10 and 50 mg?kg~(-1) zileuton groups;zileuton 50 mg?kg~(-1) also reduced the content of MDA,increased the activity of GSH-PX,and inhibited the increase of MPO in brain tissue.Conclusion Zileuton possesses the neuroprotective effects on focal cerebral ischemia-reperfusion injury in rats.
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Purpose To observe the changes of dynorphin-like immunoreactivities of neurons in some rat brain nuclei that are related to analgesia following exogenous administration of melatonin. Methods The experimental rats were divided into two groups, injected intraperitoneally with melatonin 110 mg/kg and with vehicle, respectively. One hour after the injection, the rat brain was processed for coronal sections. The sections were stained with immunohistochemical ABC technique. The integral optical density (IOD) of the stained section was measured by the computer-assisted image processing technique. Results Dynorphin-like immunoreactivities in the supraoptic nucleus and nucleus raphe dorsalis showed obvious reduction following the single injection of melatonin.IOD values in the above nuclei were decreased significantly (P<0.01) with the melatonin treatment. In the paraventricular nucleus of hypothalamus, periaqueductal gray and nucleus raphe magnus, there was no difference (P>0.05) about the IOD values between melatonin-treated group and vehicle-treated group. Conclusions Melatonin may result in the decrease of dynorphin content in the supraoptic nucleus and nucleus raphe dorsalis.
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Objective To investigate the effects of CTX-d from venoms of cobra (Naja naja atra) on inducing NB4 apoptosis and its mechanism. Methods MTT was used to detect the antitumor effect of CTX-d in vitro; Electron microscope and flow cytometry were used to observe the apoptotic inducing effect of CTX-d in NB4 cells; Mitochondrial transmembrane potential change (??m) was analyzed by flow cytometry; The levels of caspase-9, caspase-3, and cytochrome C in the cytosol fraction were analyzed by Western blotting. Results The IC50 values of CTX-d affected on NB4 cell for 6 and 12 h were 1.8 and 1.35 ?g/mL, respectively. CTX-d could induce morphological changes, such as condensed chromatin and swelling mitochondria in NB4 cells. Analyzed by flow cytometry, CTX-d induced apoptosis in NB4 cells evidenced by increasing sub G1 cell population in a dose- and time-dependent manner. The mitochondrial membrane potential of NB4 cells had already decreased when incubated with CTX-d (1.0 ?g/mL) for 0.5 h, and cytochrome C in the cytosol was detected simultaneously, which indicated the release of cytochrome C from mitochondria to cytosol. The caspase-9 was activated initially at 1 h after 1.0 ?g/mL CTX-d treatment, whereas the cleavage of caspase-3 was detected at 0.5 h. This suggested that some other mechanism may be involved in caspase-3 activation. Conclusion The results suggest that the loss of mitochondrial membrane potential and the release of cytochrome C from the mitochondria into the cytosol are the early events of CTX-d on NB4 apoptosis. Once release into the cytosol, cytochrome C precedes the activation of caspase-9 and -3 to leading to the apoptosis and there are maybe some other mechanism involved in caspase-3 activation.
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Objective To investigate the effect of lipid soluble fraction in the radix of Salvia miltiorrhiza (FSM) on conditioned place preference (CPP) in mice induced by morphine and preliminarily identify the fraction in the radix of S. miltiorrhiza. MethodsMorphine or NS was sc injected every other day to induce the obvious CPP in mice for 6 d. Before 30 min of sc injecting morphine, mice were ip administered different doses of lipid soluble fraction in the radix of S. miltiorrhiza. RP-HPLC method was used to identify the major component in the lipid soluble fraction in the radix of S. miltiorrhiza. ResultsThe staying time in morphine-paired white compartment was significantly prolonged. After treatment with lipid soluble fraction in the radix of S. miltiorrhiza (40 mg/kg, ip), the staying time in morphine-paired white compartment was significantly shortened (P
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Objective To investigate the effect of Salvia miltiorrhiza extracts on morphine physical dependence in mice. Methods The physical dependence model was induced by repeated sc morphine daily in mice and then withdrawal symptom was induced by ip naloxone. Different doses of S. miltiorrhiza extracts were administrated by ip during or after the induction phase of morphine dependence, and effects of S. miltiorrhiza extracts both by preventive and acute administration on naloxone-precipiated withdrawal symptom in mice were investigated. The potential physical dependence of S. miltiorrhiza extracts was studied. Results Compared to morphine model group, preventive administration of S. miltiorrhiza extracts (100—200 mg/kg) could reduce the number of naloxone-induced withdrawal jumps (P
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AIM To investigate the effects of ondansetron, a selective 5 Hydroxytryptamine3 (5 HT 3) receptor antagonist, on morphine physical dependence. METHODS The morphine dependent models in mice and in isolated Guinea pig ileum were used. RESULTS Pretreatment of ondansetron for 12 days significantly reduced morphine withdrawal symptoms in mice ,such as body weight loss(Groups 2～100 ?g?kg -1 ?d -1 ) or reduced both body weight loss and jumping times (Group 100 ?g?kg -1 ?d -1 ). In addition, concomitant treatment with ondansetron(1～20 ?mol?L -1 ) dose dependently suppressed the contraction induced by naloxone in Guinea pig ileum. CONCLUSION The chronic pretreatment of ondansetron can prevent morphine physical dependence to some extent.
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AIM To study the protective effects of melatonin(MT) on acute cerebral ischemia reperfusion injury.METHODS The model of cerebral ishemia-2 h/reperfusion-24 h was induced by middle cerebral artery occlusion(MCAO) in SD rats. Melatonin (10,20 mg?kg -1 ip)was administered four times in an animal:At 0, 1, 2, 6 h of reperfusion. After 24 h reperfusion, the content of malondialdehyde(MDA),the activities of superoxide dismutase(SOD)and myeloperoxidase (MPO)in brain tissue, the content of thromboxane B 2(TXB 2) and 6-keto-prostaglandin F 1?(6-keto-PGF 1?)in plasma were measured. RESULTS Compared with vehicle group, MT 10, 20 mg?kg -1 protected the activity of SOD, reduced the content of MDA, MT 20 mg?kg -1 also inhibited the increase of MPO in brain tissue ,and attenuated the disequilibrium of TXB 2 /6-keto-PGF 1?.CONCLUSION The protective effects of MT on acute cerebral ischemia reperfusion injury may be related to its increasing antioxidase activities,decreasing lipid peroxidative damage and inhibiting inflammations.
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Aim To construct eukarytic vector for rat endostatin(endos) cDNA and observe its expression in C6 cell.Methods cDNA encoding rat endostatin was amplified from newborn brain tissue with RT-PCR and inserted into the eukarytic vector pBudCE 4.1.Recombinant was identified with KpnI,XhoI double digestion,PCR and nucleotide sequencing of the target gene.After successful reconstruction of the genes of endostatin,the recombinants was transfected into C6 cells with lipofectintechniques.The positive clones were screened out through zeocin resistance test.The endostatin in supernate of the positive clones was identified with Western-blot and MTT method.With immunocytochemistry,the endostatin in the positive clones was located.The quantities of VEGF in supernate of the positive clones were quantified with ELISA assay.Results The size of the amplified endostatin gene fragment was in accord with that we expected.And the gene sequence inserted into the eukarytic vector pBudCE 4.1 was consistent with the known sequence.Endostatin was secreted from the positive clone.Down-requlation of vascular endothelial growth factor(VEGF) was found in the positive clones.Conclusion The recombinant of rat endostatin gene clone had been established and inserted into the eukarytic vector pBudCE 4.1 successfully and endostatin was expressed in C6 cells.This provides a basis for further studies of endostatin effects in vivo,and creates the conditions for final clinical trial
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AIM To study the characteristics of Ca 2+ channel mediated store operated Ca 2+ influx on rat vascular smooth muscle. METHOD Fura 2 fluorescence technique was used to investigate the [Ca 2+ ] i change. RESULTS ① S nitrosocaptopril (CapNO,20～120 ?mol?L -1 ) produced a concentration dependent inhibitory effect on cyclopiazonic acid(CPA) induced [Ca 2+ ] i change. The maximal inhibitory effect(37%?17%) of CapNO was reached at a concentration of 80 ?mol?L -1 . The same concentration of Captopril had no effects. ② Inhibition rate of 80 ?mol?L -1 CapNO (The concentration of maximal effect, CME) on CPA induced [Ca 2+ ] i change was 30%?10%, subsequent addition of 1 ?mol?L -1 Nif (CME)did not further produced the decrease effect (54%?18%). subsequent addition of 20 ?mol?L -1 SK&F96365 (CME) further produced the decrease effect. The inhibitory effects of 20 ?mol?L -1 SK&F96365 were significantly different in the cases of CapNO and Nif pretreatment(24%?10%) and non treatment (54%?11%). ③ The inhibitory effects of 2 ?mol?L -1 tyrphostinAG490(AG490,CME) were significantly different in the cases of CapNO (CME) pretreatment (24%?9%)and non treatment (42%?10%). 80 ?mol?L -1 CapNO effect on CPA induced [Ca 2+ ] i changes in AG490 pretreatment condition(18%?7%) was different from that in non treatment case(37%?10%). CONCLUSION S nitrosocaptopril obviously inhibits the opening of SOCC and VDCC, which mediates store operated Ca 2+ influx. The inhibitory effects of CapNO is associated with both sensitive to and non sensitive to tyrosine kinase (Janus2).
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AIM To study antitumor activity of melatonin in mice and its synergetic effects when MT combined with chemotherapeutic agents cytoxan(CTX). METHODS At a tolerable dose level,MT was administrated singlely or in combination with CTX to treat the transplanted murine solid tumor U 14 . The inhibition of tumor weight were observed. The weight of spleen and the hepatic cells' structure were also be measured. RESULTS The high dosed group of MT(80 mg?kg -1 ?d -1 ,sc) had a certain inhibition on the growth of the U 14 with inhibition rate of 27 1%. The low dosed group of MT(40 mg?kg -1 ?d -1 , sc) and the high dosed one combined with the CTX (25 mg?kg -1 ?d -1 ?1,ip) showed much pronounced than that of solely administration of MT. There was no significant influnce on the weight of spleen and the hepatic cells' structure. CONCLUSIONS The antitumor effect was observed by independent administration of MT. There was a synergism when MT combined with CTX but their toxicities were not obviously enhanced.
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We first report the pharmacokinetics of paeoniflorin ( PF), that is a main component of paeony roots, in dogs by HPLC analysis. The experimental results were shown that after i .v . of 11.25 mg/kg PF in 4 dogs, the curve of plasma concentrations versus times for PF was fitted well to a open 2 compartment model, the T1/2 (?) was 6.29?1.80min T1/2 ( ? ) was 133.41?84.89 min, VB was 0.54 ? 0.10 L/kg, andCL was 3.41 ? 1.01ml/min?kg-1 .The results also were shown that PF was rapidly removed from the blood by kidney and the accumulated recovery amounts of excretion was 36.85% and 79.33% of total i .v . doses during 20 min and 7h administrations respectively. The elimination of PF by liver was lower than by kidney, and the accumulated amount of PF in bile was only 3.77% within 7h after iv.