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11.
中药金安与顺铂诱导小鼠Lewis肺癌凋亡的研究   总被引:6,自引:0,他引:6  
[目的]探讨中药金安是否能促进顺铂诱导C57BL/6J小鼠Lewis肺癌凋亡。[方法]荷Lewis肺癌的C57BL/6J小鼠分为生理盐水组(NS)、金安组(JA)、顺铂组(DDP)和金安合用顺铂组(DJ),通过检测各组小鼠的体重变化和抑瘤率,应用流式细胞仪和TUNEL法以及提取组织DNA并电泳等方法观察金安合用顺铂对Lewis肺癌的治疗作用。[结果]JA组体重明显增加,DDP组体重先升后降,而DJ组体重则先升后降再回升呈“~”型。各治疗组的抑瘤率分别为40.90%、52.04%和47.83%。流式细胞仪检测各组的凋亡率依次为14.95%、11.68%和14.25%。TUNEL法测定各组的凋亡指数依次是(0.79±1.60)%、(4.00±7.15)%、(5.93±5.96)%、(7.07±10.15)%;DNA提取并电泳在DJ组有DNALadder出现。[结论]金安能增强DDP诱导Lewis肺癌的凋亡作用,并能减轻其毒副作用。  相似文献   
12.
To elucidate the early events of blood-borne metastasis under actual blood flow, real-time trafficking of RAW117 large cell lymphoma cells, namely parental RAW117-P and liver-metastatic RAW117-H10 cells, was investigated using positron emission tomography (PET). Both types of cells accumulated in the liver immediately after injection via the portal vein, and were eliminated from the liver time-dependently. The elimination rate of RAW117-H10 cells, however, was slower than that of RAW117-P cells, suggesting that RAW117-H10 cells interact more strongly with hepatic sinusoidal endothelium than the parental cells. This result correlated with the metastatic potential of these cells: RAW117-H10 cells metastasized in the liver to a greater extent than RAW117-P cells after injection via this route. To investigate the role of sialylglycoconjugates in the interaction of RAW117-H10 cells with the hepatic endothelium after injection via the portal vein, the trafficking of RAW117-H10 cells was examined after the cells had been treated with sialidase. The elimination rate of RAW117-H10 cells from liver was observed to be greatly accelerated by sialidase treatment. To elucidate what kind of sialylglycoconjugates is related to this phenomenon, we analyzed the distribution of sialyl Lewis A and sialyl Lewis X antigens of both sublines of RAW117 by using flow cytometry. RAW117-H10 cells were found to express a much higher level of sialyl Lewis A than RAW117-P cells, whereas the amount of sialyl Lewis X did not differ significantly. These findings suggest that some sialylglycoconjugates, perhaps sialyl Lewis A in particular, play an important role in the initial interaction of RAW117-H10 cells with the hepatic endothelium, leading to metastasis.  相似文献   
13.
目的:观察承气生血方对小鼠Lewis肺癌肿瘤细胞生长及转移的抑制作用。方法:采用动物移植性肿瘤实验法,在C57BL小鼠腋皮下接种Lewis肺癌肿瘤细胞,口服给药后解剖动物,剥离肿瘤,计算肿瘤生长抑制率;取肺、肝、脾组织福尔马林固定,石蜡切片,HE染色后,显微镜观察肺转移结节,计算肿瘤转移抑制率,并观察肝脾形态学变化。结果:承气生血方1.2g·kg-1/d组与模型组比较肿瘤生长抑制率36.12%,p<0.01;1.2g·kg-1/d组及0.6g·kg-1/d组肿瘤转移抑制率分别为60%和62.5%,p<0.01。形态学观察,荷瘤小鼠肺转移瘤细胞核大,深染,形态不规则; 肝细胞肿胀,胞浆疏松,但未见肝组织有瘤细胞转移;脾细胞增大,排列不规则,可见大量多核巨细胞。结论:承气生血方具有抑制小鼠Lewis肺癌肿瘤细胞生长及转移作用。  相似文献   
14.
Preclinical evidence suggests there is a link between the responsiveness to stress and the propensity to self-administer drugs of abuse. Our previous findings, for example, have shown a significant positive correlation between the locomotor response to novelty and the acquisition of morphine self-administration in Lewis (LEW), Fischer 344 (F344) and ACI inbred rat strains. As an extension of this work, we now report on the neuroendocrine responses (i.e., corticosterone and prolactin secretion) evoked by morphine administration in these same inbred strains. Male LEW, F344, and ACI rats were surgically prepared with indwelling jugular catheters 7 days prior to the study. Following a habituation period, rats were treated with i.p. saline or morphine (1, 5 or 10 mg/kg). Repeated blood samples were withdrawn via the catheters immediately before and at 20, 40, 60 and 120 min after injection. Plasma samples were assayed for hormone levels by radioimmunoassay. No differences in baseline corticosterone levels were found across strains. There was a significant effect of genotype on the corticosterone response to saline injection (i.e., mild stress), with F344 rats exhibiting sustained elevations in corticosterone compared to LEW and ACI rats. Morphine-induced stimulation of corticosterone release differed significantly across strains, and in this case LEW rats displayed a reduced sensitivity to morphine. Similar to the corticosterone results, LEW rats also had blunted prolactin responses to morphine when compared to F344 rats. Our data demonstrate that genotype is an important factor modulating the neuroendocrine sensitivity to morphine. It is noteworthy that LEW rats acquire self-administration more rapidly than F344 or ACI rats, yet LEW rats display reduced corticosterone responses to stress and morphine. Taking into account the particular conditions of this study (high i.p. doses used here vs. low i.v. doses in self-administration studies), our results do not suggest that corticosterone response to stress and morphine is related to vulnerability to intravenous opiate self-administration. The data, however, are consistent with the idea of that genetic factors might influence the sensitivity to the morphine-induced effects of glucocorticoids across these inbred strains.  相似文献   
15.
目的考察寡糖LewisA模拟肽对肺炎症性损伤的抑制作用。方法采用博莱霉素诱导小鼠肺产生炎症损伤 ,采用病理切片法观察LewisA模拟肽对炎症的影响。结果早期注射寡糖LewisA模拟肽可以抑制博莱霉素诱导的小鼠肺炎症性损伤。结论寡糖LewisA模拟肽可能作为抑制肺炎症性损伤的药物。  相似文献   
16.
Rationale Lewis (LEW) and Fischer (F344) rats exhibit marked differences in appetitive and consummatory responses to numerous drugs, including psychostimulants. Neurotensin (NT) produces psychostimulant-like actions, which sensitize with repeated exposure, and neuroleptic-like actions; effects that are dependent on the site of microinjection. The aim of the present experiments was to assess the behavioral sensitivity of these two strains of rats to NT receptor activation. Methods In expt 1, locomotor activity was assessed on alternate days following an ICV injection of NT, [d-Tyr11]neurotensin (d-NT; 18 nmol/10 μl), or vehicle (days 1, 3, 5, and 7) in independent groups of LEW and F344 rats. On day 14, locomotor activity was assessed in all rats following an injection of d-amphetamine (1 mg/kg, IP). In expt 2, activity was assessed following injection into the ventral tegmental area of NT, or d-NT, (2.5 μg/hemisphere) or into the nucleus accumbens (2.5 and 5.0 μg/hemisphere). Results Repeated ICV injections of NT, or d-NT, produced differential behavioral effects in the two strains of rats on days 1–7; activity was initially suppressed in LEW, but less so in F344 rats, following NT. In F344, but not in LEW rats, d-NT produced a significant increase in activity. Neurotensin and d-NT sensitized LEW rats to amphetamine-induced ambulatory and non-ambulatory activity. Except for vertical activity, this effect was weaker or in the opposite direction in F344 rats. When injected into the ventral tegmental area, NT produced an increase in locomotor activity in both strains, an effect that was greater in F344 than LEW rats with d-NT. In the nucleus accumbens, NT marginally decreased activity in both strains, while d-NT produced a significant increase in F344 but not in LEW rats. Conclusions These results provide empirical evidence that endogenous NT neurotransmission within limbic circuitry differs in F344 and LEW rats.  相似文献   
17.
用体内外实验模型,研究了新维A类化合物4-乙酰胺苯基维A酸酯(4-APR)对肿瘤侵袭、转移的抑制作用。4-APR 43.3mg·kg-1po即能减少小鼠Lewis肺癌的自发性肺转移瘤数。半体内实验证明4-APR10-5mol·L-1和10-6mol·L-1对B16-F10癌细胞的人工肺转移瘤数分别抑制67.9%和36.6%。体外实验显示,4-APR对B16-F10细胞侵袭重组基底膜的抑制率分别为54.2%和41.9%。  相似文献   
18.
目的观察CIK(cytokine induced killer)细胞对Lewis肺癌细胞增殖的抑制作用,探讨其抑瘤机制。方法常规方法培养CIK细胞,以CIK细胞为效应细胞,Lewis肺癌细胞为靶细胞,检测Lewis肺癌细胞的凋亡情况。结果电镜观察CIK细胞能促进Lewis肺癌细胞凋亡超微结构的改变;流式细胞仪检测CIK细胞组凋亡率明显高于对照组。结论CIK细胞可在体内及体外抑制Lewis肺癌细胞增殖,诱导肿瘤细胞凋亡。  相似文献   
19.
乙酰紫草素注射液对小鼠Lewis肺癌生长抑制的研究   总被引:4,自引:1,他引:3  
目的:探讨乙酰紫草素注射液对小鼠Lewis肺癌的生长抑制作用。方法:建立C57BL/6小鼠lewis肺癌模型进行体内抗瘤实验并计算抑瘤率。结果:乙酰紫草素注射液高中低剂量组的抑瘤率分别为55.49%,45.25%和28.09%。结论:乙酰紫草素注射液能明显抑制小鼠Lewis肺癌的生长。  相似文献   
20.
目的 研究肺复康对Lewis肺癌小鼠肿瘤生长及癌、癌旁组织中上皮-间质转化(EMT)相关因子E-钙黏蛋白(E-cadherin)、波形蛋白(Vimentin)和转化生长因子-β(TGF-β)表达的影响.方法 40只小鼠随机分为肺复康组(17.2 g生药/kg)、5-Fu组(25 mg/kg)、Lewis肺癌模型组、正常组.检测肿瘤体积、肿瘤质量以及癌、癌旁组织中E-cadherin、Vimentin和TGF-β的蛋白表达情况.结果 与模型组相比,肺复康组肿瘤体积减小(P<0.01),肿瘤质量降低(P<0.01);肺复康组抑瘤率为36%.与正常组比较,模型组癌及癌旁组织E-cadherin表达降低(P<0.01),Vimentin、TGF-β表达升高(P<0.01);与模型组癌及癌旁组织相比,肺复康组癌及癌旁组织E-cadherin表达升高(P<0.01),而Vimentin、TGF-β无显著性差异(P>0.05).结论 肺复康对Lewis肺癌小鼠肿瘤的生长具有一定的抑制作用;并能上调E-cadherin的表达,从而促进肿瘤细胞间的同质粘附而抑制肿瘤的侵袭、转移.  相似文献   
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