Ebselen对妊娠铅负荷干预

目的：探讨防止宫内铅暴露对婴儿健康影响,方法,应用原子吸收测定孕妇血铅,对志愿采用Ebselen进行干预流行病学调查,结果：至38周干预组血铅增加21．5％,显低于对照组（64．5％）,Zn含量（13.39umol/L→17.35umol/L和GSH－Px活性（73．5U/L→95.4U/L)增加,LPO含量（6.82nmol/L→5.22nmol/L)降低,差异有极显性（P均＜0．01）,结论：Ebselen对盈妇期铅增高的趋势有阻遏作用,Ebselen中的Se不参加贮存而具有增强抗氧化活性,但能促进Zn的储备,Ebselen有用于预防婴儿铅中毒的可能。     

河北甜杏仁对D-半乳糖诱导衰老模型大鼠的影响

目的　研究河北甜杏仁对D 半乳糖 (D gal)诱导衰老模型大鼠的影响。方法　给D 半乳糖衰老模型大鼠饲以不同杏仁剂量 ( 32 5、6 5、97 5g kg饲料 )的饲料 ,30天后 ,测定大鼠血清中丙二醛 (MDA)水平、超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GSH Px)的活力以及红细胞膜脂质流动性。结果　与衰老组比较 ,高、中剂量组大鼠血清中MDA明显降低 (P <0 0 1) ,SOD、GSH Px活力明显提高 (P <0 0 1) ,红细胞膜脂质流动性明显增强 (P <0 0 1)。而低剂量组各项指标均没有明显变化 (P >0 0 5 )。结论　甜杏仁具有一定的抗氧化、延缓衰老的作用     

A new key neurohormone controlling reproduction,gonadotropin-inhibitory hormone (GnIH): Biosynthesis,mode of action and functional significance

Identification of novel neurohormones that play important roles in the regulation of pituitary function is essential for the progress of neurobiology. The decapeptide gonadotropin-releasing hormone (GnRH) is the primary factor responsible for the hypothalamic control of gonadotropin secretion. Gonadal sex steroids and inhibin inhibit gonadotropin secretion via feedback from the gonads, but a neuropeptide inhibitor of gonadotropin secretion was, until recently, unknown in vertebrates. In 2000, a novel hypothalamic dodecapeptide that inhibits gonadotropin release was identified in quail and termed gonadotropin-inhibitory hormone (GnIH). This was the first demonstration of a hypothalamic neuropeptide inhibiting gonadotropin release in any vertebrate. GnIH acts on the pituitary and GnRH neurons in the hypothalamus via a novel G protein-coupled receptor for GnIH to inhibit gonadal development and maintenance by decreasing gonadotropin release and synthesis. GnIH neurons express the melatonin receptor and melatonin stimulates the expression of GnIH. Because GnIH exists and functions in several avian species, GnIH is considered to be a new key neurohormone controlling avian reproduction. From a broader perspective, subsequently the presence of GnIH homologous peptides has been demonstrated in other vertebrates. Mammalian GnIH homologous peptides also act to inhibit reproduction by decreasing gonadotropin release in several mammalian species. Thus, the discovery of GnIH has opened the door to a new research field in reproductive neurobiology. This review summarizes the advances made in our understanding of the biosynthesis, mode of action and functional significance of GnIH, a newly discovered key neurohormone, and its homologous peptides.     

络病汤对脑血管性痴呆大鼠的认知功能的影响及其机制

目的研究络病汤对血管性痴呆大鼠的认知功能及脑组织中乙酰胆碱酯酶（AchE）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH—Px）活性的影响。方法反复夹闭大鼠双侧颈总动脉结合腹腔注射硝普钠降低血压的方法制备拟血管性痴呆大鼠模型。观察络病汤对大鼠的学习记忆能力及脑组织中AchE、SOD和GSH—Px活性的影响。结果络病汤能提高血管性痴呆鼠的学习记忆能力;同时可提高SOD和GHS—Px活性,降低AchE的活性。结论改善胆碱能神经功能、减轻自由基损伤可能是络病汤改善血管性痴呆的机制之一。     

Adrenomedullin reduces antioxidant defense system and enhances kidney tissue damage in cadmium and lead exposed rats

Adrenomedullin (AdM) is synthesized and secreted by a number of cells and tissue. AdM is a potent vasodilator but it is also considered a neuromodulator, an angiogenic factor, and a hormone regulator. AdM possess antiapoptotic, antioxidant, and antimicrobial properties. Heavy metals such as cadmium and lead are found widely in the environment and they have important biological functions. Lead (Pb) and cadmium (Cd) can accumulate in the lungs, liver, bone, and kidneys and cause serious organ damage. In the present study, we investigated the effect of AdM, Pb + AdM, and Cd + AdM treatments on superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities as well as the level of malondialdehyde (MDA) in the kidney. Heavy metal accumulation was determined in kidney with and without AdM infusion and kidney damage was evaluated by light and electron microscopy. Increased heavy metal accumulation was observed in the heavy metal and AdM treated groups. SOD, CAT, GSH-Px activities, and MDA levels were significantly different in the treatment groups when compared with the control group. Tubular degeneration, necrosis, cell swelling, mononuclear cell infiltration, and degenerated organelles were observed in the kidney following treatment. Therefore, AdM infusion has no beneficial and/or compensatory role in cadmium and lead toxicity in the kidney. We conclude that heavy metal accumulation in the kidney in conjunction with AdM infusion is cytotoxic despite the known beneficial effects of adrenomedullin.     

硒诱导红白血病K562细胞凋亡机制的探讨

目的 探讨微量元素硒对人红白血病细胞株（K562细胞株）诱导凋亡的机制。方法 采用免疫光技术检测加硒培养组（实验组）K562细胞的凋亡细胞核变化和凋亡小体的数量，同时还应用化学检测与细胞凋亡有关的酶。结果 实验组凋亡细胞明显增多，且呈剂量依赖性，实验组细胞内谷胱甘肽过氧化物酶（GSH－Px)的活性及环磷酸苷（cAMP)的含量也明显高于对照（P＜0．01）。结论 硒能够诱导K562细胞凋亡，可提高该细胞内GSH－Px的活性及cAMP的含量。     

益气活血复方脂血康抗大鼠动脉内皮损伤作用的实验研究

脂血康能显著降低３６周高胆固醇膳食所致高脂血症动物血浆总胆固醇（ＴＣ）、低密度脂蛋白胆固醇（ＬＤＬｃ）和ＬＰＯ的水平，升高高密度脂蛋白胆固醇（ＨＤＬｃ）的水平，增加血中ＧＳＨ－Ｐｘ和ＳＯＤ的活性，防止血管内皮细胞损伤及平滑肌细胞的增殖和内迁。提示该复方可通过对血浆脂蛋白和氧自由基代谢的影响而预防ＡＳ病变的形成     

Kinetic analysis of the protection afforded by reversible inhibitors against irreversible inhibition of acetylcholinesterase by highly toxic organophosphorus compounds

In organophosphate poisoning, the underlying mechanism of the therapeutic efficacy of carbamate prophylaxis, which was successfully tested in animal experiments, still awaits complete understanding. In particular, it is unclear whether survival is improved by increased acetylcholinesterase activity during the acute phase, when both carbamate and organophosphate are present. This question should be solved experimentally by means of a dynamically working in vitro model. Immobilized human erythrocytes were continuously perfused while acetylcholinesterase activity was monitored in real-time by a modified Ellman method. The concentrations of reversible inhibitors and of paraoxon were varied to assess the influence of both components on the enzyme activity under steady-state conditions. Physostigmine, pyridostigmine and huperzine A were tested for their prophylactic potential. Upon pretreatment with these reversible inhibitors the enzyme was inhibited by 20-90%. Additional perfusion with 1 microM paraoxon for 30 min resulted in a residual activity of 1-4%, at low and high pre-inhibition, respectively. The residual activity was significantly higher than in the absence of reversibly blocking agents (0.3%). After discontinuing paraoxon, the activity increased even in the presence of the reversible blockers. Stopping the reversibly blocking agents resulted in 10-35% recovery of the enzyme activity, depending on the degree of pre-inhibition. The experimental results agreed with computer simulations upon feeding with the essential reaction rate constants, showing that physostigmine was somewhat superior to pyridostigmine in enhancing residual activity in the presence of 1 microM paraoxon for 30 min. The model predicts that inhibitors with a faster dissociation rate, e.g. huperzine A, may be superior in case of a 'hit-and-run' poison such as soman.     

黄磷亚急性染毒大鼠肝脂质过氧化水平的研究

研究观察了经腹腔注射黄磷（ 每次１－５ ｍｇ／ｋｇ ｂ－ｗ ．, 每周三次） 的亚急性染毒大鼠１ 周, ２ 周, ３ 周三个不同时点肝脏的超氧化物歧化酶、谷胱甘肽过氧化物酶等抗氧化酶活力及脂质过氧化物—丙二醛含量的变化关系。结果表明,黄磷亚急性染毒组肝脏中上述的抗氧化酶活性于所设三个时点中的２ 周及３ 周均比对照组低（ Ｐ＜ ０－０１） ,同时丙二醛含量高于对照组（ Ｐ＜ ０－０１） 。提示,黄磷亚急性染毒大鼠中肝脏抗氧化酶活性受黄磷毒性所抑制, 出现肝脏脂质过氧化并造成肝损害。同时, 结果也表明黄磷亚急性染毒大鼠血清中丙二醛含量与肝脏丙二醛含量存在着高度密切的正相关关系（ Ｐ＜ ０－０１） , 且前者升高的时间比血清谷丙转氨酶升高早。提示, 血清丙二醛可能可以作为黄磷亚急性染毒对肝脏损害较敏感的指标。     

竹叶提取物抗氧化作用研究

目的:观察口服竹叶提取物对老龄大鼠的抗氧化作用.方法:测定给药后大鼠红细胞SOD和全血GSH-Px及肾上腺内维生素C(VitC)含量.结果:竹叶提取物150、300mg/kg连续用药30天能升高大鼠红细胞SOD、全血GSH-Px酶活力,且能降低大鼠肾上腺皮质中VitC含量.结论:竹叶提取物能增强老龄大鼠机体抗氧化能力及提高肾上腺皮质的功能.