^125I,^131I诱发小鼠精子畸形发生率比较

本文选用 ICR 雄性小鼠,经腹腔分别注射不同剂量的~(125)I 及~(131)I,观察并比较它们对小鼠精子畸形发生率的影响及染毒后睾丸中放射性活度的变化。实验结果表明:(1)~(125)I 染毒后4—5周,0、185、370和555 kBq 各组精子畸形发生率分别为9.00‰、9.57‰、11.6‰及13.9‰;~(131)I 染毒后4—5周,上述各组精子畸形发生率分别为8.50‰、12.5‰、14.7‰和15.5‰;在相同注入量下,~(125)I 与~(131)I 诱发小鼠精子畸形发生率的差异各组均不显著(X~2检验,p>0.05)。(2)~(125)I、~(131)I 染毒后2h 至7天内,两者在睾丸中的放射性活度及变化规律相似,即在染毒后2h 达最高值,每克睾丸中~(125)I 和~(131)I 的放射性活度分别占初始注入量(370 kBq)的0.72％和0.50％,然后迅速下降,至一周时,仅分别占初始注入量的0.035％和0.011％。     

Antiobese and hypocholesterolaemic effects of an Adenophora triphylla extract in HepG2 cells and high fat diet-induced obese mice

The ethyl acetate extract from Adenophora triphylla root (ATea) had strong antioxidant effect. We hypothesised that a high fat (HF) diet might induce oxidative stress and so, dietary antioxidant may have beneficial effects on hypercholesterolaemia, but the underlying mechanisms involved are not fully understood. To test this hypothesis, C57BL/6 mice were fed with HF diet for 9 weeks. In the last 4 weeks, the HF diet was supplemented with 0, 25 or 75 mg/kg ATea. ATea decreased body weight gain and both ATea doses significantly reduced the plasma and hepatic cholesterol levels of the obese mice. Analysis of the hepatic expression of proteins known to play important roles in cholesterol metabolism indicated that ATea significantly enhanced low density lipoprotein receptor (LDL receptor) and cholesterol 7α-hydroxylase (CYP7A1) expression but inhibited the 3-hydroxy-3-methylglutaryl–CoA reductase (HMG–CoA reductase) expression in HepG2 cells and mice. No mutagenic activity was observed at high doses of ATea.     

Male Urinary Chemosignals Differentially Affect Aggressive Behavior in Male Mice

Chemical signals modulate aggressive behavior in mice. For example, male urinary cues enhance aggression against other adults: a resident mouse attacks a male but not a castrated intruder, unless it is anointed with male urine. Our purpose was to understand whether molecules excreted with urine also act as aggression triggers in a different context. Therefore, the effect of urine, or molecules purified from urine, voided by different animals (males or females), was tested on the aggression of male mice against pups. Latency to the first attack, percentage of pups receiving the first attack, and percentage of attacked pups after 5 and 15 min were recorded. At variance with intermale aggression, male urinary chemosignals sprayed on pups reduced infanticide, while female urine did not. Male urine also delayed infanticide when compared to female urine. Pups anointed with low molecular weight dialyzed urine and with the high molecular weight protein fraction were attacked later than controls. Pups anointed with Major Urinary Proteins (MUPs) also were attacked later. The volatiles retained by MUPs act in the same way as adult male urine. MUPs and their ligands did not modify biting of food items. The results show that mice do not perceive male chemosignals as compulsory aggression triggers but rather can consistently and differentially shape their behavior in response to the same molecules according to different contextual events.     

小肠RNA对小鼠电离辐射肠道损伤修复的差异基因表达的研究

为从基因水平探讨小肠糖核酸，促进小鼠电离辐射肠道操作修复的机理，采用随机分组法把９０只小鼠分成４组，建立辐射后给予４０μｇＲＮＡ治疗的实验组与０．４ｍＬ生理盐水治疗的对照组模型，分别于照射后６、１２、２４ｈ，４ｄ和８ｄ采集小肠空肠段标本，动用消减杂交基础上的ＬＤ－ＰＣＲ技术，分离实验组与对照组之间的差异表达基因。结果表明：实验组与对照组６、１２、２４ｈ，４ｄ和８ｄ的克隆新表达基因数分别为１８、２２     

保健食品促进排铅模型小鼠饮水染铅剂量及检测指标的探讨

为探讨保健食品促进排铅作用动物模型饮水染毒的适宜剂量，给小鼠自由饮用Pb^2 浓度为163．9、546．2、l638．7mg／L的醋酸铅溶液30d，每周记录饮用量，周末称重，估算实际铅摄入剂量。实验末取血、肝、脑、肾、股骨，石墨炉原子吸收分光光度法测定全血和组织铅含量。结果显示，163．9、546．2、l638，7mg Pb^2 ／L剂量组小鼠实际铅摄入剂量分别为27．9、86．6、169．4mg／kg BW，546．2、1638．7mg Pb^2 ／L剂量组小鼠体重增长较对照组显著减少，食物利用率也明显降低；各剂量组小鼠全血、肝、肾、股骨铅及546．2、1638．7mg Pb^2 ／L剂量组小鼠脑铅含量显著升高。建议以546．2mg Pb^2 ／L作为保健食品促进排铅作用饮水染毒的造模剂量；除骨铅外，建议增测肾脏、脑组织内的铅、锌、铜含量及骨骼内的钙含量。     

Reproductive and neurobehavioural effects of thiabendazole administered to mice in the diet

Thiabendazole was given in the diet to provide levels of 0 (control), 0.031, 0.125, and 0.5% from 5 weeks of age of the F₀ generation to 9 weeks of age of the F₁ generation in mice, and selected reproductive and neurobehavioural parameters were measured. The average litter size and weight were significantly reduced in the high-dose group at birth. No adverse effects were observed in the sex ratio at birth. The average body weight of offspring was significantly increased in the low-dose group during the late lactation period, and was significantly reduced in the high-dose group during the lactation period. In the assessment of neurobehavioural parameters, surface righting at postnatal day (PND) 7 was significantly delayed in a dose-related manner in both sexes. Swimming limb movement at PND 14 and olfactory orientation at PND 14 were significantly depressed in the high-dose group in both sexes. In movement activity at 3 weeks of age in the F₁ generation, vertical time and number of defaecations were significantly decreased in the high-dose group in female offspring. Several adverse effects on reproductive and neurobehavioural parameters were produced at the highest dose level of thiabendazole used in the present study (equivalent to 700-1800mg/kg bw/day). Slight, dose-related delays were also seen in surface-righting ability at the two lower dose levels. The lowest dose level (equivalent to 50-180mg/kg bw/day) is 500     

几种制剂对辐射所致脂质过氧化作用的影响

本文报道了γ射线照射对小鼠肝、脾、肾中脂质过氧化物（ＬＰ０）含量的影响，以及照后服用知母宁、单宁酸和鲨烯等制剂的抗脂质过氧化作用。制剂均灌胃给药，ＬＰＯ用改良的ＴＢＡ分光光度法测定。结果表明，γ射线整体照射小鼠后７２ｈ，其组织中ＬＰＯ含量增高，在０－４Ｇｙ范围内辐射剂量与ＬＰＯ含量呈线性关系；三种制剂均有降低小鼠肝、脾、肾中ＬＰＯ的作用，其中知母宁（０．３５ｍｇ／ｄ）的抗脂质过氧化作用显著优于单宁酸（１５ｍｇ／ｄ）和鲨烯（０．６ｍｇ／ｇ）。     

氦氖激光照射对小鼠脾淋巴细胞增殖反应影响的试验研究

目的：研究氦氖激光照射对小鼠脾淋巴细胞增殖反应的影响。方法：以BALB/c小鼠为研究对象，应用7.33，11.00,14.67,22.00和36.67j/cm^2五种剂量的氦氖激光器照射小鼠哈德腺，连续照射8d，并于照射开始后第3、6、9、13和第17d动脉监测实验鼠脾淋巴细胞增殖反反应：结果:7.33,11.00,14.67和22.00j/cm^2四个剂量组均可增强脾淋巴细胞增殖反应，但11.00，14.67和22.00j/cm^2三个剂量组在第3d就达到峰值，此后逐步下降，而7.33j/cm^2剂量组直到第9d才达到峰值，且维持时间最短。与此相反的是，36.67j/cm^2剂量组则在第3d就出现抑制效应，直至第13d才恢复至正常水平。结论：适当剂量的氦氖激光照射可对小鼠脾淋巴细胞增殖反应产生增强效应，而过大剂量He-Ne激光则对免疫机能产生抑制效应。     

微波对小鼠睾丸染色体的影响

本文使用2450MHz 连续微波照射 C_(57)BL 小鼠,观察生殖细胞染色体畸变。在功率密度约20、30及37mW/cm~2三种辐射强度下,睾丸周围的温度分別达37.5℃左右、38—39℃及40℃左右。最低辐射强度组动物的染色体畸变与对照组无差异。在其他两个辐射组,可见到细胞染色体畸变率增高,尤以高强度辐射组为明显。精原细胞的细胞染色体畸变率分别达12.16%及5.45%(对照组为1.26%);初级精母细胞第一次减数分裂的细胞染色体畸变率分别达9.31%及5.28%(对照组为2.56%)。畸变类型主要为染色单体断片、断裂,个别细胞的染色体或个別染色体出现粉碎化。