黄芩苷的耐缺氧作用

为探讨黄芩苷对心肌缺血有无治疗作用 ,用小白鼠制备模型进行了耐缺氧研究。本文采用常压耐缺氧法 ;对抗异丙肾上腺素法 ;对抗亚硝酸钠法 ;断头法 ;失血性休克法研究了黄芩苷对小鼠耐缺氧作用的影响。结果表明 ,黄芩苷能非常显著延长常压耐缺氧条件下小白鼠的存活时间 (P<0 0 1) ;能非常显著延长腹腔注射异丙肾上腺素的小白鼠在常压缺氧条件下的生存时间 (P <0 0 1) ;能非常显著缩短失血性休克小鼠心跳时间 (P <0 0 1) ;对小白鼠的亚硝酸钠中毒无显著的缓解作用 (P >0 0 5 ) ;对断头小鼠的呼吸时间无显著影响 (P >0 0 5 )。这些结果提示因黄芩苷可拮抗儿茶酚胺类化合物 ,所以对心肌氧供不足及因心肌耗氧增加引起的心肌缺氧均有非常显著的改善作用 (P <0 0 1) ;对脑缺氧无显著的改善作用 (P >0 0 5 ) ;对亚硝酸钠引起的组织中毒性缺氧无显著的缓解作用 (P >0 0 5 )。     

粗壮女贞耐缺氧作用的实验研究

目的 探讨粗壮女贞对小鼠的抗缺氧作用.方法 通过小鼠亚硝酸钠中毒小鼠存活时间实验、小鼠急性脑缺血性缺氧存活时间实验研究粗壮女贞的耐缺氧功能.结果 与正常对照组相比,粗壮女贞能明显延长亚硝酸钠中毒后的小鼠存活时间和急性脑缺血性缺氧状态下小鼠的存活时间.结论 粗壮女贞能提高小鼠的耐缺氧能力.     

α-倒捻子素耐缺氧作用的初步研究

目的研究α-倒捻子素对缺氧小鼠的作用。方法小鼠给予α-倒捻子素一定时间后,采用亚硝酸盐建立缺氧模型,考察小鼠的生存时间。结果α-倒捻子素高剂量条件下可以显著延长小鼠的生存时间。结论α-倒捻子素具有一定的耐化学缺氧作用,可以用于缺氧、缺血性损伤的保护,具体作用机制有待进一步研究。     

泥鳅多糖对小鼠耐缺氧作用的研究

目的　研究泥鳅多糖 (MAP)对小鼠耐缺氧作用的影响。方法　连续灌胃小鼠不同剂量的泥鳅多糖 14d ,末次给药后 1h ,进行密闭缺氧实验、亚硝酸钠中毒缺氧实验和急性脑缺血性缺氧实验。以存活时间、Hb、MDA含量及SOD活性为指标 ,观察MAP对小鼠耐缺氧作用的影响。结果　实验结果表明 ,MAP可延长小鼠在不同缺氧条件下的存活时间 ,以 5 0mg·kg-1·d-1剂量效果最佳。MAP可增高小鼠血红蛋白含量 ,抑制组织脂质过氧化反应以及增加血浆中SOD活性。结论　MAP具有提高实验小鼠耐缺氧能力的作用     

五子衍宗丸对小鼠抗疲劳、耐缺氧作用的影响

目的:探讨五子衍宗丸的滋补强壮作用机理.方法:通过小鼠游泳实验、缺氧条件下生存时间实验,考察五子衍宗丸的抗疲劳、耐缺氧作用以及对于小鼠脾指数和胸腺指教的影响.结果:五子衍宗丸能显著延长小鼠游泳时间、增强耐缺氧时间,并能增强小鼠免疫功能.结论:五子衍宗丸具有抗疲劳、耐缺氧及免疫增强作用,是仍具开发潜力的保健中药.     

白芍总甙耐缺氧作用的实验研究

安徽毫县产白芍提取的白芍总甙(TGPs5～40mg/kg)呈剂量依赖性延长小白鼠常压缺氧存活时间。TGPs(20mg/kg)可延长小白鼠减压缺氧存活时间,降低小鼠整体氧耗量,并有降温作用,TGPs(40mg/kg)可降低小白鼠氰化钾中毒性缺氧的死亡率。氯苯吡胺(5mg/kg)可明显拮抗TGPs耐缺氧作用。TGPs(2.5～5mg/kg)小鼠icv可明显延长小鼠常压缺氧存活时间,此作用可被氯苯吡胺拮抗。     

沙棘粉对小鼠耐寒冷耐缺氧耐疲劳的影响

本文观察了沙棘粉混悬液对小鼠耐寒冷、耐缺氧和游泳抗疲劳的影响。实验中发现,沙棘粉可以提高小鼠在低温环境下的耐寒冷能力,与对照组比较,差异有显著性(P<0.01);同时也能延长小白鼠在低温下的游泳时间,提高抗疲劳能力,结果与对照组比较,有显著性差异(P<0.01);还可以延长小白鼠在常压下的耐缺氧时间,高剂量组比对照组提高了82.71%,低剂量组比对照组提高了53.29%。     

来复汤对小复耐缺氧能力的影响

来复汤为近代名医张锡纯的“救脱”常用方，为进一步探索其治疗“厥脱证”的现代药理学机制，本试验观察了该方水煎剂对小鼠常压耐缺氧能力的影响，对异丙肾上腺素处理的小鼠常压在耐缺氧能力的影响、对氰化钾中毒缺氧小鼠的影响以及对小鼠减压缺氧能力的影响，结果证实其对小鼠的上述四种耐缺氧能力均有明显的增强作用（Ｐ〈０．０５），这种作用可能是其抗休克作用的基础之一。     

景蜂胶囊对小鼠的耐缺氧作用

目的研究景蜂胶囊对小鼠耐缺氧作用的影响。方法连续给予小鼠不同剂量的景蜂胶囊10 d,末次给药1 h后,进行密闭缺氧、亚硝酸钠中毒缺氧和急性脑缺血性缺氧实验。以存活时间、血红蛋白(Hb)、丙二醛(MDA)的含量和超氧化物歧化酶(SOD)的活性为指标,观察景蜂胶囊对小鼠耐缺氧作用的影响。结果景蜂胶囊可延长小鼠在不同缺氧条件下的存活时间,增加小鼠Hb的含量,抑制脂质过氧化反应并增加血清中SOD活性。结论景蜂胶囊具有提高小鼠耐缺氧能力的作用。     

通心络对兔缺氧耐受性的影响

目的观察通心络对兔急性缺氧耐受性的作用。方法 24只新西兰大耳白家兔随机分为对照组、缺氧组和通心络组,先在11.4%氧环境下低氧实验,60min后进行密闭缺氧,观察兔密闭缺氧耐受时间,ELISA法检测血清缺氧诱导因子1-α(HIF-1α)的含量、Western blot法检测主动脉组织HIF-1α和血管内皮生长因子(VEGF)的蛋白表达。结果与缺氧前比较,缺氧组与通心络组血清HIF-1α含量明显增加(P<0.01或P<0.05)。与对照组比较,缺氧组和通心络组主动脉组织HIF-1α和VEGF表达明显增强(P<0.01或P<0.05)。与缺氧组比较,通心络组家兔密闭缺氧耐受时间明显增加(P<0.05),血清HIF-1α含量明显增加(P<0.01),主动脉组织HIF-1α表达增强,VEGF表达明显增强(P<0.05)。结论 HIF-1α和VEGF的表达增高可能是缺氧适应的一种机制,通心络能提高兔的缺氧耐受性,其机制可能与上调血清及组织的HIF-1α和VEGF有关。     

Task-specific tolerance to d-amphetamine

Rats were trained concurrently on sweetened-milk drinking and bar-press-responding behavior, which alternated on a daily basis. Dose-response functions for d-amphetamine were determined before and after conditions of chronic treatment. When given before chronic treatment, d-amphetamine decreased both milk consumption and reinforcement received for lever-pressing in a dose-dependent manner. Subsequently, three conditions of chronic injection were established in which one group received saline, prior to both tasks, another group received d-amphetamine prior to drinking milk and saline prior to lever-pressing and the third group received d-amphetamine prior to lever-pressing and saline before drinking milk. The rats became tolerant to d-amphetamine in the task in which the drug had been administered chronically; however, the same rats showed no tolerance in the other task in which saline had been administered chronically. Tolerance to d-amphetamine was thus shown to be behaviorally specific.     

羊胎盘复方制剂对小白鼠免疫功能和缺氧耐受力的影响

目的以山羊胎盘为主要原料配制成胎盘复方制剂,研究其对小白鼠免疫功能与缺氧耐受力的影响。方法雌性小鼠40只随机等量分成羊胎盘复方制剂高(1 g/kg.体重)、中(0.5 g/kg.体重)、低(0.1 g/kg.体重)3个剂量组和1个对照组(生理盐水),灌胃30 d后测定各指标(免疫器官指数、耳重差、中毒与缺氧的存活时间)。结果免疫功能试验中,与对照组相比,高、低剂量组有显著差异(P<0.05),中剂量组有极显著水平(P<0.01)。小鼠脾脏指数与对照组相比,高、低剂量组能显著影响小鼠的脾脏指数(P<0.05)。迟发型变态反应试验中只有高剂量组耳重差与对照组耳重差相比差异极显著(P<0.01);在缺氧耐受力试验中,除中毒存活试验的中剂量组存活时间与对照组相比差异不显著(P>0.05)外,其它剂量组存活时间与对照组相比均有显著差异(P<0.05)。结论羊胎盘复方制剂具有提高小鼠机体免疫功能和增强机体缺氧耐受力的作用。     

糖皮质激素对内毒素耐受的影响

目的应用地塞米松(dexamethasone,Dex)干预小鼠内毒素耐受的形成,研究糖皮质激素对内毒素耐受的影响。方法以昆明鼠为实验对象进行分组,ⅠA组为健康对照组,ⅠB组为单次直接致死剂量脂多糖(lipopolysaccharide,LPS)(2LD50=8 mg/kg)对照组,Ⅱ组为标准内毒素耐受组,ⅢA组为初始LPS刺激前高剂量Dex(10 mg/kg)干预组,ⅢB组为终末致死量LPS前高剂量Dex干预组,ⅣA组为初始LPS刺激前低剂量Dex(1mg/kg)干预组,ⅣB组为终末致死量LPS前低剂量Dex干预组。完成实验处置后3 h取血标本,应用ELISA方法检测血清TNF-α和IL-10水平。结果①ⅠA组TNF-α、IL-10水平极低,ⅠB组TNF-α、IL-10水平较ⅠA组显著增高(P<0.05,P<0.01),Ⅱ组TNF-α、IL-10水平较ⅠB组显著下降(P<0.05,P<0.01),但仍高于ⅠA组。②各Dex干预组TNF-α水平与Ⅱ组比较:ⅢA、ⅣA组TNF-α水平与Ⅱ组TNF-α水平差异无统计学意义(P>0.05),ⅢB、ⅣB组TNF-α水平低于Ⅱ组,差异有统计学意义(P<0.05)。③各Dex干预组IL-10水平与Ⅱ组比较:ⅢA、ⅣA组IL-10水平高于Ⅱ组,差异有统计学意义(P<0.05),ⅢB、ⅣB组IL-10水平与Ⅱ组比较差异无统计学意义(P>0.05)。结论①LPS刺激可导致小鼠体内TNF-α水平、IL-10水平升高。内毒素耐受时,小鼠体内TNF-α、IL-10水平升高的程度明显降低。②终末LPS前一定时间内予以Dex干预可以促进内毒素耐受的形成,Dex剂量过高可能不会带来更多受益。③IL-10对内毒素耐受的形成可能不具有决定作用。     

咖啡因对健康成人糖耐量的影响

目的:观察口服400 mg咖啡因对正常成人糖耐量的影响。方法:采用单盲、安慰剂对照的随机临床研究。46位年龄在25～40岁的健康成人在4周观察期内需戒饮茶,咖啡,可口可乐或巧克力,并写下知情同意书。观察期结束后,随机分为两组分别服用1周咖啡因或安慰剂,进行葡萄糖耐量测试。结果:在前2 h,两组受试者血糖值正常且相似,但到第3,4 h,口服咖啡因组受试者与空白对照组比较,糖耐量曲线明显左移,血浆胰岛素水平略有增加。结论:健康成人口服咖啡因有降低血糖的作用,且伴有胰岛素水平轻微升高的依赖作用。     

Effect of raphe lesions on the development of acute tolerance to ethanol and pentobarbital

The effect of electrolytic lesions in the median and dorsal raphe nuclei was tested on acute tolerance development to ethanol and pentobarbital in the rat, as measured by motor impairment on the moving belt test. Acute tolerance to ethanol (1.7 g/kg, IP) or pentobarbital (17.5 mg/kg, IP) was monitored at 12.5, 25, or 50 min in separate subgroups tested only once each. One week of recovery was allowed between ethanol and pentobarbital tests. Median raphe lesions delayed the development of acute tolerance, whereas dorsal raphe lesions produced a negligible effect. These results were seen with both ethanol and pentobarbital. The mesolimbic 5-HT pathway from the median raphe nucleus is important in the development of acute tolerance to ethanol and pentobarbital, as was shown to be the case previously for chronic tolerance.     

Effect of perinatal hypoxia on cardiac tolerance to acute ischaemia in adult male and female rats

1. The number of adult patients undergoing surgery for congenital cyanotic defects in childhood has increased significantly. Therefore, the aim of the present study was to examine the effect of perinatal hypoxia on the tolerance of the adult myocardium to acute ischaemia-reperfusion injury. 2. Pregnant Wistar rats were exposed to intermittent hypobaric hypoxia 7 days before delivery; pups were born under normoxic conditions and exposed to hypoxia again for 10 postnatal days. After the last hypoxic exposure, all animals were kept for an additional 3 months under normoxic conditions. All experiments were performed on 90-day-old rats. 3. Ventricular arrhythmias were assessed on isolated perfused hearts during 30 min occlusion of the left anterior descending coronary artery. Infarct size was measured on isolated hearts (40 min regional ischaemia and 120 min reperfusion) and on open-chest animals (20 min regional ischaemia and 3 h reperfusion). 4. Perinatal exposure to hypoxia significantly increased cardiac tolerance to ischaemic injury in adult females, as evidenced by the lower incidence and severity of ischaemic ventricular arrhythmias, compared with the normoxic group. The effect of perinatal hypoxia on ischaemic arrhythmias in males was quite the opposite. Myocardial infarct size measured in open-chest animals only was significantly smaller in normoxic females compared with normoxic males. Perinatal exposure to hypoxia had no effect on infarct size in either setting or sex. 5. The results of the present study support the hypothesis that perinatal hypoxia is a primary programming stimulus in the heart that may lead to sex-dependent changes in cardiac tolerance to acute ischaemia in later adult life. This would have important implications for patients who have experienced prolonged hypoxaemia in early life.     

Effect of fluoxetine on tolerance to the analgesic effect of morphine in mice with skin cancer

Adjuvant drugs that attenuate or inhibit the development of tolerance to morphine may lead to improved management of pain in chronic diseases such as cancer. The aim of this study was to investigate effect of fluoxetine, a specific 5-HT (5-hydroxytryptamine, serotonin) reuptake inhibitor, on tolerance induced to the analgesic effect of morphine in mice with skin cancer. The study was carried out on female Swiss albino mice. For skin tumorigensis, mice were initiated with a single dose of 7,12-dimethylbenz(a)anthracene (DMBA) and promoted by multiple doses of croton oil. Tolerance to morphine analgesia was induced by daily subcutaneous (sc) injections of morphine (5 mg/kg for 30 days) and assayed using the hot plate method. Results obtained from this study showed that pain thresholds in mice with skin cancer were significantly lower. Tolerance to the analgesic effect of morphine (5 mg/kg, sc) appeared at day 15, whereas in normal and skin tumor bearing mice co-treated daily with morphine (5 mg/kg, sc) and three different intraperitoneal (ip) doses of fluoxetine (0.16, 0.32 and 0.64 mg/kg) tolerance was observed at days 20, 25 and 30, respectively. In conclusion, our data indicate that concurrent use of morphine with fluoxetine may produce good cancer pain control and attenuate the development of tolerance.     

葡萄糖耐量减低患者二甲双胍干预治疗的临床效果

目的:对葡萄糖耐量减低(impaired glucose tol-erance,IGT)患者予以药物二甲双胍和生活方式干预治疗,前瞻性观察(1年)IGT患者的血糖和颈总动脉内膜-中层厚度(intima-media thickness,IMT)的变化。方法:对葡萄糖耐量减低患者随机分为生活方式治疗组(A组)和二甲双胍药物(250 mg,每日3次)联合生活方式治疗组(B组)治疗1年,1年后复测葡萄糖耐量试验和颈总动脉IMT。结果:在基础状态时,两组的血糖和颈总动脉IMT差异无统计学意义。1年后B组餐后2 h血糖明显低于A组[分别为(7.9±1.2)(、8.7±1.4)mmol/L,P=0.002],B组IMT的增加值明显低于A组[分别为(0.001±0.010)、(0.007±0.014)mm,P=0.042]。结论:二甲双胍治疗明显改善IGT患者的餐后血糖,并能延缓动脉粥样硬化的发展。     

泰山四叶参精制多糖对小鼠耐缺氧及抗疲劳能力的影响

目的:观察通过D101大孔树脂精制的4年生泰山四叶参多糖对小鼠耐缺氧和抗疲劳能力的影响。方法:用水提醇沉法和大孔树脂对四叶参多糖进行提取和纯化,得到精制的四叶参多糖。昆明种小鼠,按照性别和体质量随机分4组(n=10),分别为对照组,高、中、低3个剂量组,灌胃10d后,采用耐缺氧和负重游泳的实验方法,测定小鼠不同时间的累计耗氧量,缺氧存活时间和负重游泳存活时间。结果:高剂量组可明显降低小鼠累计耗氧量,延长小鼠缺氧存活时间和负重游泳存活时间。结论:4年生泰山四叶参大孔树脂精制多糖具有明显的提高小鼠耐缺氧及抗疲劳能力的作用。