1,2-二氯乙烷染毒对小鼠脑组织氨基酸类神经递质的影响

探讨1,2-二氯乙烷(1,2-DCE)对小鼠脑组织氨基酸类神经递质的影响,为揭示1,2-DCE的神经毒性损伤机制提供实验参考数据。将昆明种小鼠随机分为4组,对照组和不同剂量1,2-DCE染毒组(0.25 mg/L、0.50 mg/L、1.00mg/L),每组10只小鼠。静式吸入染毒14 d,每天染毒2 h。染毒结束后取大脑组织,测定小鼠脑脏器系数;高效液相色谱法(HPLC)检测脑组织中谷氨酸(Glu)、天冬氨酸(Asp)、甘氨酸(Gly)、牛磺酸(Tau)及γ-氨基丁酸(GABA)的含量。结果小鼠脑脏器系数随染毒剂量的增加呈下降趋势,但各组间差异无统计学意义。各染毒组的Asp、Glu和Tau含量随染毒剂量的增加而升高,且中、高剂量染毒组与对照组比较差异有统计学意义;各染毒组的Gly含量随染毒剂量的增加也有升高的趋势,但与对照组比较差异无统计学意义;中剂量染毒组的GABA含量与对照组比较差异具有统计学意义,但高剂量组与对照组比较未见明显差异。提示亚急性1,2-DCE暴露可引起小鼠脑组织中氨基酸类神经递质含量的异常,其可能是1,2-DCE神经毒性损伤的主要机制之一。 更多还原     

十溴联苯醚(BDE-209)染毒对雄性BALB/c小鼠睾丸毒性作用

目的 探讨十溴联苯醚(BDE-209)染毒对雄性BALB/c小鼠睾丸组织脂质过氧化指标的影响及其睾丸组织形态学变化.方法 21只雄性BALB/c小鼠随机分为高剂量染毒组、低剂量染毒组和对照组,每组7只,分别给予500 mg/kg BDE-209(高剂量组)、200 me/kg BDE-209(低剂量组)和0.1ml/10 g体重生理盐水(对照组),经灌胃给药,每日1次,连续染毒6周.测定小鼠体重、睾丸重量,测定睾丸组织还原型谷胱甘肽(GSH)、丙二醛(MDA)含量和超氧化物歧化酶(SOD)活力,观察睾丸组织形态学变化,TUNEL法检测睾丸细胞凋亡的改变.结果 高、低剂量组小鼠体重和睾丸重量均明显低于对照组,差异有统计学意义(P＜0.05).高剂量染毒组睾丸脏器系数为(0.8640%±0.1706%)明显高于对照组(0.8329%±0.1386%),差异有统计学意义(P＜0.05).高、低剂量染毒组睾丸组织中GSH水平和SOD活力分别为(0.044±0.006)、(0.039±0.005)nmol/mg和(0.735±0.179)、(0.907±0.198)U/mg,明显低于对照组[(0.052±0.067)nmol/mg prot]和[(1.161±0.188)U/mg],差异有统计学意义(P＜0.05);高、低剂量染毒组睾丸组织MDA含量分别为(2.365±0.339)、(1.752±0.366)nmol/mg,高于对照组[(1.173±0.232)nmol/mg],差异有统计学意义(P＜0.05).与低剂量染毒组相比,高剂量染毒组睾丸组织中SOD活力降低,MDA含量升高,差异有统计学意义(P＜0.05).组织形态学观察可见,染毒组生精细胞的数目和层次明显减少,且排列层次紊乱,支持细胞数目减少,小管中心明显萎缩.TUNEL实验结果表明,染毒组睾丸细胞出现少量凋亡细胞.结论 BDE-209可引起雄性BALB/c小鼠睾丸组织脂质过氧化指标的改变,对睾丸有一定的毒性作用.

Abstract：

Objective To explore the lipid peroxidation and the testicular morphological change induced by decabrominated diphenyl ether (BDE-209) in male BALB/c mice. Methods Twenty one male BALB/c mice were randomly divided into three groups: the high exposure group (500 mg/kg BDE-209), the low exposure group (200 mg/kg BDE-20) and control group (normal saline). The mice were exposed by gavage one time a day for 6weeks, then were sacrificed. Body weight, testis weight, malonyldialdehyde (MDA),total supemxide dismutase (T-SOD) and glutathione (GSH) in testis were examined. the morphological alteration of testis was observed. TUNEL assay was used to detect the apoptosis in testicular cells. Results Body weight and testis weight in high and low exposure groups were (21.6140 ± 2.3550)g, (20.8000 ±1.7630)g and (0.1859±0.0349) g, (0.1718±0.0266) g, respectively, which were significantly lower than those (27.7570±1.2880) g and (0.2302±0.0335)g in the control group (P＜0.05); the testis coefficient in high exposure group was (0.8640%±0.1706%), which was significantly higher than that (0.8329±0. 1386%) in the control group (P＜0.05). The GSH level and SOD activities of testis in 2 BDE-209 groups were 0.044±0.006,0.039±0.005 nmol/mg prot, and 0.735±0.179, 0.907±0.198 U/mg prot, respectively, which were significantly lower than those (0.052±0.067) mol/mg and (1.161 ±0. 188) U/mg in the control group (P＜0.05). The levels of MDA in 2 BDE-209 groups were (2.365±0.339) and (1.752±0.366) nmol/mg prot, which were significantly higher than that (1.173±0.232 nmol/mg prot) in control group (P＜0.05). there were significant differences of SOD and MDA levels between high exposure group and low exposure group (P ＜0.05). Histological examination showed that the number of spermatogenic cells and layer were decreased significantly in 2 exposure groups as compared with control group. TUNEL assay showed that apoptosis cells appeared in 2 exposure groups. Conclusion BDE-209 changed lipid peroxidation in male BALB / c mice testis and caused toxic effects on the testis.     

1,2-二氯乙烷对淋巴细胞DNA损伤的γH2AX识别抗体流式细胞术检测

目的 探讨γH2AX识别抗体流式细胞术(FCM)检测1,2-二氯乙烷(1,2-DCE)接触工人外周血淋巴细胞DNA损伤的可行性及1,2-DCE对健康人外周血淋巴细胞DNA的损伤.方法 提取某制鞋厂接触1,2-DCE的工人21例(接触组)和该厂未接触1,2-DCE的工人27例(内对照组)及某海岛非职业接触有害因素居民28例(外对照组)的外周血淋巴细胞,采用FCM法检测淋巴细胞DNA损伤情况;用不同浓度(5、10、20和30 μmol/L)的1,2-DCE分别对健康人外周血淋巴细胞体外染毒0.5、1.0 h,采用FCM法检测淋巴细胞DNA损伤情况.结果 接触组工人DNA损伤率(4.05%±2.55%)明显高于内对照组工人(1.97%±1.40%)和外对照组人群(0.23%±0.13%),内对照组明显高于外对照组,差异均有统计学意义(P＜0.01或P＜0.05);接触组工人外周血淋巴细胞的几何平均荧光强度(3.33±3.01)与内对照组(2.07±0.58)比较,差异有统计学意义(P＜0.05).接触组不同工龄工人DNA损伤率和外周血淋巴细胞的几何平均荧光强度比较,差异均无统计学意义(P＞0.05).体外染毒0.5 h时,20、30μmol/L染毒组外周血淋巴细胞的几何平均荧光强度与阴性对照组比较,差异有统计学意义(P＜0.01).体外染毒1.0 h时,20、30μmol/L染毒组的DNA损伤率与阴性对照组比较,差异有统计学意义(P＜0.05,P＜0.01),10、20、30 μmol/L染毒组外周血淋巴细胞的几何平均荧光强度与阴性对照组比较,差异均有统计学意义(P＜0.05,P＜0.01).结论 1,2-DCE具有遗传损伤作用,FCM法是一种检测外周血淋巴细胞DNA损伤的有效方法.

Abstract：

Objective To study DNA damage of human peripheral blood lymphocytes exposed to 1,2dichloroethane (1,2-DCE) with flow cytometry (FCM) assay. Methods The lymphocytes were obtained from 21 workers who are occupationally exposed to 1, 2-DCE (exposed group ) and 27 workers who were not exposed to 1,2-DCE in the same factory (inner control ) and 28 island residents who had never been occupationally exposed to adverse factors (external control ). FCM assay was adopted to detect DNA damage of the lymphocvtes of each group. Lymphocytes of the health people were incubated with 1 ,2 - DCE at different doses, and FCM assay was used to detect DNA damage. Results DNA damage rate (%) of the exposed group of exposed workers (4.05%±2.55%) was significantly higher than the inner control group of workers ( 1.97%± 1.40% ) and external control groups of island residents (0.23%±0.13%), and the DNA damage of inner control was higher than the external control, all the differences were statistically significant (P＜0.01 or P＜0.05 ).The geometric mean fluorescence intensity of the workers in the exposed group (3.33±3.01) was significantly higher than the (2.07±0.58) only (P＜0.05). There was no significant difference in the DNA damage rate as well as the geometric mean fluorescence intensity among the exposed group of workers with different years of working period (P＞0.05). In vitro, the fluorescence intensity at the dose of 20,30 μmol/L for 0.5 h exposure showed statistical significance compared with the negative control group (P＜0.01). The DNA damage rate at the dose of 20, 30μmol/L for 1.0 h exposure was statistically significant compared with the negative control group (P＜0.05,P＜0.01 ); The fluorescence intensity at the dose of 10,20,30 μmol/L for 1.0 h exposure was statistically significant compared with the negative control group(P＜0.05,P＜0.01 ). Conclusion 1 ,2-DEC can cause DNA damage. And γH2AX FCM assay can be a sensitive, objective and effective method of detecting DNA damage of peripheral blood lymphocytes.     

甲醛致扩张性简单串联重复序列突变小鼠子代对四氯化碳和苯暴露易感性研究

目的 探讨甲醛染毒致基因组扩张性简单串联重复序列(ESTR)突变小鼠的子代对外源性化学物的易感性.方法 选择经甲醛染毒小鼠繁殖的有ESTR突变的F1子代小鼠(H组)与对照组小鼠(C组),在洁净环境中饲养传代至F10代.以F5和F10代小鼠分别建立四氯化碳(CCl4)致小鼠肝脏损伤模型(CCl4处理组腹腔注射含有CCl4的橄榄油10 ml/kg,CCl4浓度分别为0.05%、0.50%和5.00%)和苯致小鼠血液毒性模型(腹腔注射苯染毒剂量分别为500、1000 mg/kg).分别测定小鼠血清中丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)活力及肝脏组织中超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量,观察肝脏组织病理学变化以评价肝氧化损伤程度;检测小鼠胸骨骨髓嗜多染红细胞微核率以评价苯的血液毒性.结果 C组F5代0.50%、5.00%CCl4染毒剂量组小鼠血清中ALT、AST活力,F10代3个CCl4染毒剂量组ALT活力和0.50%、5.00%CCl4染毒剂量组AST活力,H组F5、F10代3个CCl4染毒剂量组ALT活力和0.50%、5.00%CCl4染毒剂量组AST活力均明显高于溶剂对照组,差异均有统计学意义(P<0.05,P<0.01).与溶剂对照组比较,C组F5、F10代0.50%、5.00%CCl4染毒剂量组小鼠肝匀浆中SOD活力明显降低,F10代0.50%、5.00%CCl4染毒剂量组小鼠肝匀浆中MDA含量明显升高,差异有统计学意义(P<0.05);H组F5代0.50%、5.00%CCl4染毒剂量组,F10代5.00%CCl4染毒剂量组小鼠肝匀浆中SOD活力明显降低,F5代3个CCl4染毒剂量组,F10代0.50%、5.00%CCl4染毒剂量组小鼠肝匀浆中MDA含量明显升高,差异均有统计学意义(P<0.05).甲醛染毒后基因组ESTR突变的F5代小鼠对CCl4的相对易感性比对照组相应子代明显增加,而F10代小鼠对CCl4的相对易感性明显降低.CCl4染毒后小鼠肝脏细胞坏死和脂肪变性均呈现剂量-效应关系,而且在H组明显较C组严重.C组及H组苯染毒小鼠骨髓细胞微核率(C组500 mg/kg苯染毒组:F5代为5.88‰±4.55‰,F10代为8.25‰±2.06‰;C组1000 mg/kg苯染毒组:F5代为7.50‰±6.99‰,F10代为10.67‰±1.16‰;H组500 mg/kg苯染毒组:F5代为7.88‰±3.09‰,F10代为9.20‰±1.30‰;H组1000 mg/kg苯染毒组:F5代为9.63‰±4.34‰,F10代为13.33‰±2.08‰)随苯剂量的增加而增加,与溶剂对照组(C组F5代为1.13‰±0.35‰,F10代为1.20‰±0.82‰;H组F5代为1.25‰±0.46‰,F10代为1.33‰±1.03‰)的差异均有统计学意义(P<0.05,P<0.01).结论 甲醛暴露引起的基因组ESTR突变可改变子代小鼠对CCl4和苯的易感性.ESTR突变可能是影响机体对化学物易感性的生物学标志,其分子机制有待进一步阐明.

Abstract：

Objective To investigate the susceptibility to carbon tetrachloride and benzene in offspring of expanded simple tandem repeats (ESTR) mutation mice exposed to formaldehyde (FA). Methods F5 and F10 offspring (200 mg/m3 ×2 hours) served as H group and ICR mice were used as control group(group C). The F5 and F10 offspring were exposed to 10 ml/kg carbon tetrachloride at the doses of 0.05%, 0.50% or 5.00% for 24 hours, respectively or 500 or 1000 mg/kg benzene for 24 hours, respectively by intraperitoneal injection. Serum alanine transaminase (ALT), aspartate transaminase (AST) and the hepatic superoxide dismutase (SOD) or malondialdehyde (MDA) were detected; also the hepatic pathological changes were observed under light microscope; the micronucleus in sternum bone marrow cells as the biomarker of benzene blood toxicity were measured. Results ALT and AST activities in group C of F5 mice exposed to 0.50% and 5.00% CCl4, ALT in groups C and H of F10 mice exposed to 0.05%, 0.50%, 5.00% CCl4, AST in groups C and H of F10 mice exposed to 0.50% and 5.00% CCl4 were significantly higher than those in controls, respectively (P<0.05); as compared to the control, hepatic SOD activities in group C of F5 and F10 mice exposed to 0.50% and 5.00% CCl4, in group H of F5 mice exposed to 0.50% and 5.00% CCl4, and F10 mice exposed to 5.00% CCl4 were significantly reduced, respectively (P<0.05); however, MDA contents in group C of F10 mice exposed to 0.50% and 5.00% CCl4, in group H of F5 mice exposed to 0.05% and 0.50%, 5.00% CCl4 and F10 mice exposed to 0.50% and 5.00% CCl4 were significantly increased than those in control group, respectively (P<0.05). The susceptibility to CCl4 in ESTR mutation F5 mice exposed to FA was significantly higher than that in control F5 mice, but the susceptibility to CCl4 in ESTR mutation F10 mice exposed to FA was significantly lower than that in control F10 mice. The histopathological examination showed that the injury of hepatocytes in C and H groups significantly increased CCl4 doses, and the injury of hepatocytes in H group was higher than that in C group. The micronuclear rates in C and H group mice exposed to benzene (500 mg/kg C group, F5 and F10 mice; 1000 mg/kg C group, F5 and F10 mice; 500 mg/kg H group, F5 and F10 mice; 1000 mg/kg C group, F5 and F10 mice) were 5.88‰±4.55‰, 8.25‰±2.06‰, 7.50‰±6.99‰, 10.67‰±1.16‰, 7.88v±3.09‰, 9.20‰±1.30‰, 9.63‰±4.34‰ and 13.33‰±2.08‰, respectively, which were significantly higher than those (1.13‰±0.35‰, 1.20‰±0.82‰, 1.25‰±0.46‰, 1.33‰±1.03‰) in the solvent control group(P<0.05 or P<0.01). Conclusion FA could result in the change of susceptibility to CCl4 and benzene in offspring of ESTR mutation mice. ESTR mutation may be a biomarker of the susceptibility to chemicals, but the molecular mechanisms should be investigated in the future.     

出生后早期接触功夫菊酯对仔鼠大脑突触蛋白表达的影响

Objective To evaluate the influence on the synaptic protein expression in different brain regions of ICR mice after lambda-cyhalothrin (LCT) exposure during postnatal period. Methods Two male and 4 female healthy ICR mice were put in one cage. It was set as pregnancy if vaginal plug was founded.Offspring were divided into 5 groups randomly, and exposed to LCT (0.01% DMSO solution) at the doses of 0.1, 1.0 and 10.0 mg/kg by intragastric rout every other day from postnatal days (PND) 5 to PND13, control animals were treated with normal saline or DMSO by the same route. The brains were removed from pups on PND14, the synaptic protein expression levels in cortex, hippocampus and striatum were measured by western blot. Results GFAP levels of cortex and hippocampus in the LCT exposure group increased with doses, as compared with control group (P＜0.05), while Tuj protein expression did not change significantly in the various brain regions of ICR mice. GAP-43 protein expression levels in the LCT exposed mouse hippocampus and in female ICR mouse cortex increased with doses. as compared with control group (P＜0.05). Presynaptic protein (Synapsin Ⅰ) expression levels did not change obviously in various brain regions. However, postsynaptic density protein 95 (PSD95) expression levels of the hippocampus and striatum in male offspring of 10.0 mg/kg LCT group, of cortex of female LCT groups, and of female offspring in all exposure groups, of striatum, in 1.0 or 10.0 mg/kg LCT exposure groups significantly decreased (P＜0.05). Conclusions Early postnatal exposure to LCT affects synaptic protein expression. These effects may ultimately affect the construction of synaptic connections.     

百草枯对发育中小鼠学习记忆能力的影响

目的 探讨百草枯对发育中小鼠学习记忆能力的影响及可能的氧化损伤机制.方法 80只健康21 日龄断奶未成熟昆明种小鼠随机分为低、中、高剂量百草枯染毒组和对照组(四蒸水),每组20只,百草枯染毒剂量分别为0.89、2.67、8.00mg/kg,经口灌胃(1次/d),连续染毒28 d.采用Morris水迷宫和避暗穿梭实验测定小鼠学习记忆能力,微孔板比色法测定血清和海马组织中丙二醛(MDA)含量、超氧化物歧化酶(SOD)活力及谷胱甘肽过氧化物酶(GSH-Px)活力.结果 Morris水迷宫实验中,各染毒组小鼠逃避潜伏期[(57.98±2.78)、(62.35±3.18)、(85.57±5.10)s]均明显高于对照组[(21.74±1.36)s],差异有统计学意义(P<0.05),并有剂量-反应关系(R=0.8629,P<0.05).避暗穿梭实验中,各染毒组小鼠主动回避潜伏期[(5.56±0.29)、(6.08±0.22)、(8.32±0.38)s]高于对照组[(3.50±0.13)s],差异有统计学意义(P<0.05),并有剂量-反应关系(R=0.9579,P<0.05).中、高剂量染毒组血清中MDA含量[(24.76±1.76)、(31.10±4.57)nmol/ml]明显高于对照组[(16.38±6.26)nmol/ml],差异有统计学意义(P<0.05);各染毒组海马组织中MDA含量[(2.26±0.18)、(2.77±0.20)、(3.37±0.39)nmol/mg Pro]明显高于对照组[(1.93±0.39)nmol/mg Pro],差异有统计学意义(P<0.05);各染毒组小鼠血清和海马组织中SOD及GSH-Px活力均低于对照组,差异有统计学意义(P<0.05).结论 百草枯可诱导的发育中小鼠海马组织氧化损伤,并导致小鼠学习记忆能力减退.

Abstract：

Objective To explore the damages of paraquat to the learning and memory ability of developing mice and explore the possible mechanism involving oxidative stress.Methods Eighty healthy Kunming mice in aged 21 days were divided into 4 groups randomly:a control group (distilled water) and three paraquat treatment groups.The doses of paraquat were 0.89,2.67 and 8mg/kg body weight,respectively.Paraquat was administered orally in doses of 0.1 ml/10 g body weight,respectively,once a day and for 28 consecutive days.The Morris water maze test and the shuttling and avoid dark box test were used to detect the learning and memory abilities of mice.The levels of MDA and the activities of SOD and GSH-PX were detected according to the commercial kits manual using a microplate reader.Results Morris water maze test showed that the escape latency of mice after paraquat treatment (57.98 ±2.78,62.35 ±3.18,85.57 ±5.10) were significantly increase compared with the control (21.74±1.36),respectively (P<0.05).There were good dose-response relationship (R=0.8629,P<0.05).The shuttling and avoid dark box test showed that initiative avoidance latency of mice after paraquat treatment (5.56 ±0.29,6.08 ±0.22,8.32 ±0.38) were significantly increase compared with the control (3.50 ±0.13),respectively (P<0.05).There were good dose-response relationship (R=0.9579,P<0.05 ).The levels of MDA in serum of mice in paraquat treatment groups (2.67 and 8mg/kg) (24.76±1.76,31.10±4.57) and in hippocampus of mice in each paraquat treatment groups were significantly increase compared with the control (serum:16.38±6.26,hippocampus:1.93±0.39) (P<0.05,respectively).The activities of SOD in serum and hippocampus of mice in each paraquat treatment groups were significantly decrease compared with the control (serum:213.25±6.78,hippocampus:197.36±6.37) (P<0.05,respectively).The activities of GSH-PX in serum and hippocampus of mice in each paraquat treatment groups were significantly decrease compared with the control (serum:583.47±11.23,hippocampus:412.38±13.16) (P<0.05,respectively).Conclusion Paraquat can induce the oxidative damage in hippocampus,and then influence the learning and memory abilities of developing mice.     

百草枯和代森锰慢性暴露对小鼠黑质纹状体多巴胺能系统的影响

目的 研究农药百草枯(praquat,PQ)和代森锰(maneb,MB)单独和(或)联合暴露对小鼠黑质致密部(substanitial nigra compact,SNc)脑区多巴胺(dopamine,DA)能系统的影响,并探讨其与帕金森症(Parkinson's disease,PD)发病的关系.方法 将120只健康清洁级5周龄昆明小鼠随机分为对照(生理盐水)组、PQ(5 mg/kg)组、MB(15mg/kg)组、PQ(5mg/kg)+MB(15 mg/kg)组,每组30只.采用腹腔注射方式进行染毒,染毒剂量为10 ml/kg,每周染毒2次,连续染毒16周.采用爬杆试验和开阔试验检测小鼠运动行为的变化,对SNc区域进行组织病理学观察和神经元细胞计数.以荧光分光光度法检测纹状体(Caudate putamen,CPu)脑区中DA的含量.结果 各组动物体重间比较,差异均无统计学意义(P＜0.05).染毒前和染毒8、16周后,各组小鼠的爬杆时间和跨格数间比较,差异均无统计学意义(P＞0.05).与对照组比较,染毒8、16周后PQ+MB组小鼠中脑SNc区神经元呈现胞体固缩样退化形态,细胞数量显著减少(P＜0.01);而PQ组和MB组无显著性变化(P＞0.05).与对照组比较,染毒16周后第1天仅PQ+MB组小鼠纹状体脑区DA含量较高,差异有统计学意义(P＜0.01);而PQ组和MB组小鼠纹状体脑区DA含量无显著性变化(P＞0.05).结论 单独PQ或MB低剂量长期暴露对SNc脑区的神经元无影响,二者低剂量联合暴露可导致SNc神经元损伤和丢失,表明PQ和MB的协同神经毒性可能与帕金森症发病有关.

Abstract：

Objective To investigate the effects of paraquat (PQ), maneb (MB) or their combined exposure on neurons of substantial nigra compact in mice, and to research the relationship between pesticides and Parkinson' s disease. Methods One hundred and twenty Kunming mice aged five weeks were randomly divided into 4 groups: control group(saline), PQ group(5 mg/kg), MB group (15 mg/kg) and PQ (5 mg/kg) +MB (15 mg/kg)group,30 in each. Mouse was treated with the pesticides through intraperitoneal injection (10 ml/kg),twice a week for 16 consecutive weeks. Spontaneous behaviors were examined by using the pole test and open field test. Histopathological examination was done and neurons were counted in substantia nigra compact. The dopamine concentration in caudate putamen (Cpu) were analyzed by fluorescencespectrophotometry. Results No significant average body weight change was observed among groups and no significant difference was observed in the time of pole test and the times of crossing grids between exposed groups and control group (P>0.05) before administration and after 8 weeks and 16 weeks of administration. Cell pyknosis and neurodegeneration in substantial nigra were observed in the PQ+MB group for 8 weeks and 16 weeks (P<0.01). Compared with the control group,only the PQ+MB group showed increased DA concentration in Cpu at the first day after 16 weeks of administration (P<0.01). Conclusion Chronic exposure to low-dose PQ or MB may not induce SNc neurons damage in mice. However,chronic exposure to PQ and MB in combination can cause neurons damage and neuron loss in SNc, which clues that synergetic neurotoxic effect of PQ and MB may be involved in Parkinson' s disease.     

出生后早期接触功夫菊酯对仔鼠大脑突触蛋白表达的影响

目的 观察出生后早期功夫菊酯(LCT)染毒对ICR仔鼠不同脑区突触蛋白表达的影响.方法 健康清洁级ICR小鼠按2∶4(雄∶雌)合笼受孕,出生小鼠每窝随机分为5组,分别为0.1、1.0和10.0 mg/kg LCT染毒组及溶剂对照组(0.01%二甲亚砜)和生理盐水对照组,每组雌雄各4只,仔鼠出生当天为出生后第0天(PND 0),PND5开始灌胃染毒,隔天1次,连续5次,PND14取材.蛋白质印迹法检测皮层、海马、纹状体突触蛋白的表达.结果 与溶剂对照组比较,各染毒组雄性仔鼠和10.0mg/kg组雌性仔鼠海马组织及1.0、10.0 mg/kg组雄性仔鼠和10.0 mg/kg组雌性仔鼠皮层胶质原纤维酸性蛋白(GFAP)表达升高,差异均有统计学意义(P＜0.05),且有剂量相关性(雄性:r海马=0.986,r皮层=0.945;雌性:r诲马=0.993,r皮层=0.969,P＜0.05);仔鼠各脑区的β微管蛋白Ⅲ型(Tuj)表达无明显改变;10.0 mg/kg组雄性仔鼠和各染毒组雌性仔鼠的海马及10.0 mg/kg组雌性仔鼠皮层生长相关蛋白43(GAP-43)表达升高,差异均有统计学意义(P＜0.05),且有剂量相关性(雄性:r海马=0.882;雌性:r海马=0.997,r皮层=0.99,P＜0.05);仔鼠各脑区的突触蛋白Ⅰ(Synapsin Ⅰ)表达无明显改变.10.0 mg/kg组雄性仔鼠海马、纹状体及雌性仔鼠皮层组织,各染毒组雌性仔鼠海马组织及1.0、10.0 mg/kg组纹状体组织突触后致密蛋白95(PSD95)表达降低,差异均有统计学意义(P＜0.05),PSD95表达与染毒剂量呈依赖性下降(雄性:r海马=-0.991;雌性:r纹状体=-0.996,r皮层=-0.995,P＜0.05).结论 出生后早期接触LCT,对仔鼠大脑突触蛋白的表达均有一定的影响;提示LCT可能影响仔鼠大脑突触联系的构建.

Abstract：

Objective To evaluate the influence on the synaptic protein expression in different brain regions of ICR mice after lambda-cyhalothrin (LCT) exposure during postnatal period. Methods Two male and 4 female healthy ICR mice were put in one cage. It was set as pregnancy if vaginal plug was founded.Offspring were divided into 5 groups randomly, and exposed to LCT (0.01% DMSO solution) at the doses of 0.1, 1.0 and 10.0 mg/kg by intragastric rout every other day from postnatal days (PND) 5 to PND13, control animals were treated with normal saline or DMSO by the same route. The brains were removed from pups on PND14, the synaptic protein expression levels in cortex, hippocampus and striatum were measured by western blot. Results GFAP levels of cortex and hippocampus in the LCT exposure group increased with doses, as compared with control group (P＜0.05), while Tuj protein expression did not change significantly in the various brain regions of ICR mice. GAP-43 protein expression levels in the LCT exposed mouse hippocampus and in female ICR mouse cortex increased with doses. as compared with control group (P＜0.05). Presynaptic protein (Synapsin Ⅰ) expression levels did not change obviously in various brain regions. However, postsynaptic density protein 95 (PSD95) expression levels of the hippocampus and striatum in male offspring of 10.0 mg/kg LCT group, of cortex of female LCT groups, and of female offspring in all exposure groups, of striatum, in 1.0 or 10.0 mg/kg LCT exposure groups significantly decreased (P＜0.05). Conclusions Early postnatal exposure to LCT affects synaptic protein expression. These effects may ultimately affect the construction of synaptic connections.     

百草枯和代森锰联合染毒对大鼠黑质纹状体系统的影响

目的 观察百草枯(paraquat,PQ)和代森锰(maneb,MB)联合染毒对大鼠运动行为和黑质纹状体系统神经元形态及电活动的影响,以探讨这两种农药与帕金森病(Parkinson's disease,PD)发病的关系.方法 37只大鼠随机分为对照组(11只)、PQ组(PQ 10mg/kg,13只)、PQ(10mg/kg)和MB(30 mg/kg)联合染毒组(PQ+MB组13只),每周2次腹腔注射,染毒6周,观察动物在斜板试验、网格试验和开阔试验中运动行为的变化情况;HE染色观察黑质神经元形态;利用细胞外电生理学方法记录纹状体神经元自发电活动.结果 与对照组或同组染毒前比较,PQ组及PQ+MB组大鼠从斜板上下滑次数增加,在网格上移动潜伏期延长,在开阔试验中自发运动减少,差异均有统计学意义(P＜0.05或P＜0.01).染毒后PQ组及PQ+MB组大鼠黑质致密部神经元出现受损形态改变,PQ组及PQ+MB组细胞密度分别为(82.17±12.91)和(41.15±6.44)个/mm2,与对照组[(143.10±20.85)个/mm2]比较,差异有统计学意义(P＜0.01).PQ组纹状体神经元的平均放电频率为(5.97±7.30)Hz,PQ+MB组为(6.95±9.87)Hz,较对照组[(1.78±5.05)Hz]明显提高,差异均有统计学意义(P＜0.01);PQ+MB组神经元混合簇状放电比例(22.3%)较对照组(9.8%)和PQ组(5.6%)明显增加,差异有统计学意义(P＜0.05,P＜0.01).结论 MB能加重PQ对大鼠黑质纹状体系统的损伤效应,表明这两种农药的协同毒性作用与PD发病相关联.

Abstract：

Objective To investigate the effects of exposure of paraquat and maneb on the behavior,the morphology and electrical activity of the Substantianigra and striatum, and to discuss the relationship between this two pesticides and Parkinson's disease. Methods 37 rats were divided randomly into 3 groups:control group(n=11 ), paraquat ( 10 mg/kg) group (n=13) and combinative group of paraquat ( 10 mg/kg) and maneb(30 mg/kg)(n= 13 ), and were exposed twice a week for 6 weeks by intraperitoneal injection. The behavior of animals in the declined-plane, the vertical-grid and the open-field test were observed. The morphology of substantia nigral neurons were investigated by HE pathology. The spontaneous discharge of striatum neurons were recorded after exposure. Results Compared to the control group and the pre-exposure group, both the numbers of animals sliding down from the declined-plane and the latency of rats' moving on the vertical-grid significantly increased, and the animals' autonomic movement decreased significantly (P＜0.05,P＜0.001). After the combinative exposure, the neurons of the Substantial nigra pars compacta (SN Pc ) were progressively impaired, the cell density of the paraquat group [(82.17±12.91 ) n/mm2] and the combined group [(41.15±6.44 )n/mm2] were lower than that in control group( 143.10±20.85 n/mm2) (P＜0.01). In the paraquat group(5.97±7.30 Hz) and the combined group [(6.95±9.87 ) Hz], the average discharge rates of the striatum neurons were increased significantly compared to the control group [( 1.78±5.05 ) Hz] (P＜0.01).The bursting discharge was increased significantly in the combined group(22.3% ) compared to the control group(9.8% ) and the paraquat group (5.6%) (P＜0.05,P＜0.01). Conclusion The co-exposure of paraquat and maneb could induce similar symptoms to Parkinsonism syndrome of rats such as rigidity, moving reduction and etc, and the combined exposure had a certain enhanced effect compared to alone paraquat exposure. The combinative exposure of paraquat and maneb could cause neural loss in SNPc and it is involved with the enhanced electrophysiological activity in striatum. The synergy toxicity of paraquat and maneb in nigrostriatal system is related to Parkinson's disease.     

十溴联苯醚(BDE-209)染毒对雄性BALB/c小鼠睾丸毒性作用

Objective To explore the lipid peroxidation and the testicular morphological change induced by decabrominated diphenyl ether (BDE-209) in male BALB/c mice. Methods Twenty one male BALB/c mice were randomly divided into three groups: the high exposure group (500 mg/kg BDE-209), the low exposure group (200 mg/kg BDE-20) and control group (normal saline). The mice were exposed by gavage one time a day for 6weeks, then were sacrificed. Body weight, testis weight, malonyldialdehyde (MDA),total supemxide dismutase (T-SOD) and glutathione (GSH) in testis were examined. the morphological alteration of testis was observed. TUNEL assay was used to detect the apoptosis in testicular cells. Results Body weight and testis weight in high and low exposure groups were (21.6140 ± 2.3550)g, (20.8000 ±1.7630)g and (0.1859±0.0349) g, (0.1718±0.0266) g, respectively, which were significantly lower than those (27.7570±1.2880) g and (0.2302±0.0335)g in the control group (P＜0.05); the testis coefficient in high exposure group was (0.8640%±0.1706%), which was significantly higher than that (0.8329±0. 1386%) in the control group (P＜0.05). The GSH level and SOD activities of testis in 2 BDE-209 groups were 0.044±0.006,0.039±0.005 nmol/mg prot, and 0.735±0.179, 0.907±0.198 U/mg prot, respectively, which were significantly lower than those (0.052±0.067) mol/mg and (1.161 ±0. 188) U/mg in the control group (P＜0.05). The levels of MDA in 2 BDE-209 groups were (2.365±0.339) and (1.752±0.366) nmol/mg prot, which were significantly higher than that (1.173±0.232 nmol/mg prot) in control group (P＜0.05). there were significant differences of SOD and MDA levels between high exposure group and low exposure group (P ＜0.05). Histological examination showed that the number of spermatogenic cells and layer were decreased significantly in 2 exposure groups as compared with control group. TUNEL assay showed that apoptosis cells appeared in 2 exposure groups. Conclusion BDE-209 changed lipid peroxidation in male BALB / c mice testis and caused toxic effects on the testis.     

兴奋性氨基酸与1,2-二氯乙烷急性中毒性脑病关系的探讨

目的　探讨兴奋性氨基酸 (EAAs)与 1 ,2 二氯乙烷 (1 ,2 DCE)急性中毒性脑病的关系。方法　将SD大鼠随机分为 7组 :对照组、3个染毒组 (5 .0、1 0 .0、2 0 .0g/m31 ,2 DCE)和 3个时间组(1 0 .0g/m31 ,2 DCE染毒后 2、4、6h) ;连续静式吸入染毒 1 2h ;干湿重法测定大鼠脑皮质和髓质含水量 ;高效液相色谱法 (HPLC)检测脑组织中谷氨酸 (Glu)、天冬氨酸 (Asp)、甘氨酸 (Gly)及γ 氨基丁酸(GABA)含量的变化。结果　 (1 )大鼠脑皮质和髓质含水量 :不同剂量染毒组大鼠脑皮质含水量分别为 76 .1 0 %± 1 .41 %、76 .45 %± 0 .75 %、79.95 %± 1 .45 % ,均高于对照组 (74.2 2 %± 1 .77% ) ,差异有显著性 (P <0 .0 5 ,P <0 .0 1 ) ;髓质含水量仅 2 0 .0g/m3组 (71 .77%± 3 .0 7% )有明显升高 ,差异有显著性(P <0 .0 5)。染毒后 2、4、6h脑皮质含水量分别为 79.36 %± 2 .1 0 %、79.48%± 1 .2 1 %、80 .64 %±1 .93 % ,均高于 1 0 .0g/m3即刻组 ,差异有显著性 (P <0 .0 5)。 (2 ) 4种氨基酸递质含量 :不同剂量染毒组Asp含量分别为 (4.83± 0 .35)、(7.1 7± 0 .40 )、(1 0 .52± 0 .39) μmol/g ;Glu含量分别为 (2 3 .86± 0 .62 )、(31 .2 1± 2 .50 )、(2 8.2 3± 1 .58) μmol/g;Gly含量分别为 (5 .59±     

p38 MAPK/AP-1信号通路在1，2-二氯乙烷中毒性脑水肿形成中对iNOS表达的上调作用

目的探究p38 MAPK/AP-1信号通路在小鼠1?2-二氯乙烷(1?2-DCE)中毒性脑水肿形成过程中对诱导型一氧化氮合酶(iNOS)表达的作用及其对脑水肿的影响。方法选取40只雌性昆明种小鼠随机分为对照组、染毒组、低剂量以及高剂量p38抑制剂组。染毒小鼠于染毒柜中1.2 mg/L 1?2-二氯乙烷染毒3.5 h/d,连续染毒3 d,低、高剂量抑制剂组小鼠于染毒前1 h腹腔注射200μl 3.75、15 mg/kg的p38 MAPK抑制剂(SB202190)。染毒结束次日取材,测定各组小鼠脑含水量及HE病理观察脑水肿,Western Blot检测各组小鼠脑组织中磷酸化p38、激活蛋白1(AP-1)两个亚基c-fos、c-jun的磷酸化形式表达水平以及iNOS的蛋白表达,Real-Time RT-PCR检测iNOS mRNA表达水平。结果单纯染毒组的小鼠出现抱爪现象,SB202190干预能够明显改善1?2-DCE中毒小鼠的抱爪症状。染毒组小鼠脑组织含水量与对照组小鼠相比明显增加,SB202190干预能够有效缓解小鼠出现脑水肿。单纯染毒组小鼠脑组织中p-p38蛋白、磷酸化c-jun和c-fos表达水平明显上调,iNOS蛋白和mRNA表达水平也显著增加,而SB202190能够显著降低iNOS、磷酸化c-jun和c-fos的表达水平。结论小鼠脑组织iNOS mRNA和蛋白表达水平在1?2-DCE中毒性脑水肿形成过程中显著上调。p38 MAPK/AP-1信号通路参与iNOS表达增多的调控过程。     

维生素Ｅ对1，2-二氯乙烷中毒性脑水肿保护作用的研究

目的探讨维生素E (vitamin E,Vit E)对1,2-二氯乙烷(1,2-dichloroethane,1,2-DCE)中毒性脑水肿的保护作用。方法将雌性昆明种小鼠随机分为空白对照组、Vit E对照组、1,2-DCE单纯染毒组及Vit E低、中和高剂量干预组。连续给予药物灌胃4 d后,采取静式吸入方式染毒3. 5 h/d,持续3 d。结果与空白对照组相比,单纯染毒组小鼠脑组织呈现明显脑水肿病理改变,脑含水量、脑组织中丙二醛(malondialdehyde,MDA)含量及细胞色素P450 2E1 (cytochrome P450 2E1,CYP2E1)蛋白和mRNA表达水平显著升高,脑组织中还原型谷胱甘肽(glutathione,GSH)含量、超氧化物歧化酶(superoxide dismutase,SOD)和过氧化氢酶(catalase assay kit,CAT)活性、Occludin蛋白和mRNA及Claudin 5蛋白表达水平显著降低。与单纯染毒组相比,各干预组小鼠的脑含水量、脑组织MDA含量、CYP2E1蛋白和mRNA表达水平显著降低,GSH含量、Occludin蛋白及mRNA水平显著升高;中和高剂量干预组的小鼠脑组织中SOD和CAT活性及Claudin 5蛋白表达水平亦显著升高(P0. 05)。结论单纯1,2-DCE染毒可引起小鼠脑水肿,诱导脑组织中CYP2E1的表达,诱发脑组织氧化损伤,破坏紧密连接蛋白,并抑制Occludin和Claudin 5的表达;而Vit E干预可显著抑制CYP2E1的表达,缓解CYP2E1介导的氧化损伤,有效预防1,2-DCE引起的中毒性脑水肿。     

亚急性1,2-二氯乙烷染毒致小鼠肝组织氧化损伤的研究

本研究的目的是探讨亚急性1,2-二氯乙烷(1,2-DCE)中毒致肝脏氧化损伤情况,为阐明1,2-DCE中毒性肝损伤的机制提供参考依据。将昆明种小鼠随机分成对照组和不同剂量1,2-DCE染毒组(0.35、0.7、1.2 mg/L),采用静式吸入方式染毒1周;然后,取血和肝组织,分别检测血中总胆红素(TB)和谷胱甘肽(GSH)含量,肝组织中丙二醛(MDA)、GSH含量及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性。结果中、高剂量染毒组小鼠的血浆中TB含量显著高于对照组小鼠;而中、高剂量染毒组小鼠的肝组织中GSH-Px活性和GSH含量及高剂量组的SOD活性显著低于对照组,高剂量染毒组小鼠的肝组织中MDA含量显著高于对照组。提示亚急性1,2-DCE中毒可引起肝组织的氧化性损伤。     

挥发性有机物对小鼠脑组织形态学和氨基酸类递质的影响

目的通过挥发性有机物(VOCs)对小鼠脑组织中递质类氨基酸含量的影响,探讨VOCs对小鼠神经系统的毒性。方法采用静式吸入染毒,小鼠亚急性暴露于挥发性有机物,设置对照、低(甲醛1.5mg/m3;VOCs20mg/m3)、中(甲醛4.5mg/m3;VOCs60mg/m3)、高浓度暴露组(甲醛13.5mg/m3;VOCs180mg/m3),染毒结束后,做脑组织常规病理,采用高效液相色谱法测定小鼠脑组织(皮质和海马)氨基酸类递质[包括兴奋性氨基酸类递质谷氨酸(Glu)、门冬氨酸(ASP);抑制性氨基酸类递质氨基丁酸(GABA)、甘氨酸(Gly)]含量。结果暴露组小鼠脑组织皮质和海马兴奋性氨基酸类递质含量随染毒浓度增加而降低,而抑制性氨基酸类递质含量随染毒浓度增加而增加。脑组织病理表现为VOCs暴露组神经元变性坏死。结论挥发性有机物引起小鼠学习记忆能力下降和麻醉作用。     

气态甲醛吸入染毒对小鼠水迷宫学习成绩及海马神经递质的影响

目的 探讨甲醛对小鼠学习记忆的影响,并通过测定单胺类神经递质及氨基酸类神经递质含量的变化初步探讨甲醛对学习记忆影响的机制.方法 选择雄性昆明小鼠30只,随机分为对照组、1.34 mg/m3染毒组、4.02 mg/m3染毒组,每组10只,分别置于3个216L的透明玻璃柜中染毒,对照组通以室外洁净空气,1.34、4.02mg/m3甲醛染毒组分别通以1.34、4.02 mg/m3的甲醛气体,每天染毒4 h,共7 d,测定染毒后小鼠在通道式水迷宫中学习成绩及海马神经递质含量.结果 2个染毒组与对照组小鼠在水迷宫中的游泳时间差异均无统计学意义(P＞0.05),甲醛染毒后第5天和第7天,4.02mg/m3染毒组小鼠游泳错误次数较对照组增加,均有统计学意义(均P＜0.05);4.02 mg/m3染毒组海马中5-羟色胺(5-HT)、多巴胺(DA)、去甲肾上腺素(NE)含量较对照组升高,均有统计学意义(均P＜0.05);1.34mg/m3染毒组甘氨酸(Gly)含量较对照组降低,有统计学意义(P＜0.05),各组小鼠海马中谷氨酸(Glu)、天冬氨酸(Asp)、氨基丁酸(GABA)含量差异无统计学意义.结论 吸入甲醛可影响小鼠的学习记忆能力,这可能与海马神经递质含量的变化有关.     

1，2-二氯乙烷致中毒性脑病中神经细胞的变化

目的用体外实验方法研究1,2-二氯乙烷染毒后神经细胞形态学的变化。方法将体外培养的新生SD大鼠的脑皮质细胞,分为设对照组、低、中、高剂量组,观察各组细胞形态学、超微结构和细胞活力的变化。结果染毒后神经细胞形态和超微结构均发生明显变化：在荧光显微镜下随着染毒剂量的增高,细胞核由亮绿色变为桔红色,胞体胀大甚至消失;在透射电镜下染毒组神经细胞的细胞核核膜溶解消失,染色质聚集深染,线粒体和内质网等细胞器肿胀,崩解,且线粒体嵴排列紊乱甚至消失;各染毒组神经细胞活力比对照组有所下降,差异有统计学意义（P〈0．05）。结论1,2-二氯乙烷可以导致神经细胞水肿坏死,并且有剂量依赖关系,随着染毒剂量的增加神经细胞破坏程度越大。     

醇酸涂料释放挥发性有机化合物对小鼠脑组织神经递质的影响

目的 研究醇酸涂料释放挥发性有机化合物对小鼠脑组织神经递质含量的影响.方法 将56只二级BALB/c小鼠随机分成7组(对照组,3 d染毒组,6 d染毒组,8 d染毒组,10 d染毒组,20 d恢复组,30 d恢复组),每组8只.采用动式吸入染毒的方法(醇酸涂料释放挥发性有机化合物浓度为30 mg/m3),测定连续染毒期及恢复期小鼠脑组织乙酰胆碱、单胺类(多巴胺、5-羟色胺、去甲肾上腺素、肾上腺素)、氨基酸类(谷氨酸、天冬氨酸、甘氨酸、γ-氨基丁酸)神经递质的变化规律.结果 在接触挥发性有机化合物的过程中,在染毒第3、6、8、10天,小鼠脑组织中乙酰胆碱、多巴胺、5-羟色胺、去甲肾上腺素含量低于对照组,差异均有统计学意义(P＜0.05,P＜0.01);在染毒第8、10天,小鼠脑组织中谷氨酸含量显著低于对照组,差异均有统计学意义(P＜0.01);小鼠脑组织中甘氨酸在染毒第6、8、10天、γ-氨基丁酸在染毒第3、6天含量高于对照组,差异均有统计学意义(P＜0.05,P＜0.01).脱离该环境后去甲肾上腺素含量仍然不能恢复到正常水平(P＜0.01).结论 醇酸涂料释放挥发性有机化合物能够造成小鼠脑组织神经递质的改变.     

1,2-二氯乙烷对血脑屏障的损伤作用

目的 探讨1,2-二氯乙烷对血脑屏障的损伤作用.方法 用1,2-二氯乙烷静式呼吸道急性染毒复制大鼠急性中毒性脑病模型,用硝酸镧染色法测定脑组织的含水量并检测血脑屏障的通透性;同时在体外培养脑微血管内皮细胞和神经胶质细胞,用1,2-二氯乙烷对生长良好的脑微血管内皮细胞和神经胶质细胞染毒,在光镜和电镜下观察细胞形态学特征.结果 （1）脑组织主要表现为细胞外水肿,镧示踪法检测到血脑屏障有镧颗粒的大量渗漏.（2）中高剂量染毒组大鼠大脑皮质含水量较对照组明显升高,并且随着染毒后时间的延长更趋严重;大脑髓质含水量仅在染毒后观察6 h组有统计学意义（P＜0.05）.（3）1,2-二氯乙烷能破坏脑微血管内皮细胞和神经胶质细胞的正常形态学结构,且对神经胶质细胞的损伤表现得较早、较严重.结论 1,2-二氯乙烷可造成血脑屏障的损伤,引起血管源性脑水肿.     

1，2－二氯乙烷对大鼠神经细胞内钙离子浓度的影响

[目的]用体外实验方法研究1,2-二氯乙烷（1,2-DCE）染毒后大鼠神经细胞内钙离子（Ca^2＋）浓度的变化。[方法]体外培养新生SD大乳鼠脑皮质细胞,分别用0．5、1．0、2．0mL/L1,2-DCE染毒,另设对照组,观察各组神经细胞形态学变化。同时应用激光共聚焦显微镜测定各组细胞内Ca^2＋浓度,探讨1,2-DCE对大鼠神经细胞内Ca^2＋浓度的影响。[结果]神经细胞染毒后,神经细胞形态发生明显改变：胞体肿胀崩解、胞核模糊不清、突触变短变粗、细胞间连接减少、细胞膜不完整;随着染毒剂量的增高,神经细胞损伤的严重程度呈上升趋势。各染毒组神经细胞活力较对照组有所下降,差异有统计学意义（P〈0．01）;染毒2h后随着染毒剂量的增加,各组神经细胞内Ca^2＋浓度呈上升趋势,各染毒组细胞与对照组比较差异有统计学意义（P〈0．01）;染毒24h后,低、中剂量组与对照组细胞内Ca^2＋浓度比较差异有统计学意义（P〈0．01）,高剂量组与对照组比较差异无统计学意义（P〉0．05）。[结论]1,2-DCE可以导致神经细胞水肿坏死,有剂量依赖关系,神经细胞内Ca^2＋浓度亦见升高,提示Ca^2＋可能与1,2-DCE致神经细胞中毒性脑水肿有关。