鱼藤酮对小鼠脑神经递质多巴胺及其代谢产物的影响

研究了注射鱼藤酮对C57BL/6N小鼠神经递质多巴胺的影响。给小鼠皮下注射鱼藤酮(10 mg/kg)两次,间隔2 h,在第2次注射8 h后分离脑组织样品,并应用高效液相色谱仪配电化学检测器,测定了小鼠脑内多巴胺(DA)及其主要代谢物3,4-二羟苯酰乙酸(DOPAC)和高香草酸(HVA)的水平。结果表明,第2次注射8 h后,鱼藤酮处理组的脑内DA、DOPAC和HVA水平分别比对照组高40.5%、544.4%和168.2%,差异显著(P<0.01)。实验显示,鱼藤酮对多巴胺能神经系统具有毒性作用。     

乙烯利对昆明种小鼠的氧化应激作用

选用小鼠血清及脾脏组织中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力及丙二醛(MDA)含量为观察指标,从机体氧化和抗氧化系统是否失衡的角度研究了乙烯利的氧化应激作用。结果表明,乙烯利能明显降低小鼠血清及脾脏组织中SOD和GSH-Px的活性。其中:134,268 mg/kg bw剂量处理组血清SOD和GSH-Px活性分别降低了8.91% ,12.44%和4.18% ,8.54% ;268, 536 mg/kg bw剂量组脾脏SOD和GSH-Px活性分别降低了8.34% ,19.61%和9.72%,24.86% ;与对照组差异显著(PP<0.01)。结果显示,乙烯利能破坏小鼠机体氧化和抗氧化系统的平衡,引起氧化应激。     

左炔诺孕酮-炔雌醚对长爪沙鼠的不育效果

采用强制给药的方式测定左炔诺孕酮-炔雌醚复合剂(EP-1)对雌性长爪沙鼠Meriones unguiculatus的不育效果。将试鼠分多剂量、单剂量及对照三组。多剂量组按照10mg/kg剂量,每周给药3天,连续4周;单剂量组按10mg/kg剂量仅给药1次;对照组与多剂量组同时等量以食用油灌胃。4周后与对照组比较,多剂量组子宫、卵巢的形态及其脏器系数、卵巢组织、血清雌二醇(E2)和促黄体生成激素(LH)的含量均有明显变化,且试鼠完全不育;单剂量组未发现子宫、卵巢等性腺的变化,血清E2、LH与对照组的差异不显著,且给药后1个月雌鼠可繁殖正常后代。结果表明,连续给药对雌性长爪沙鼠有生殖抑制作用。     

苯醚甲环唑亚急性经口暴露对大鼠卵巢功能的影响

苯醚甲环唑应用广泛，在食用农产品中存在残留超标现象，并在不孕女性人群血清和卵泡液中有检出。为探究苯醚甲环唑亚急性经口暴露后对卵巢功能的影响，本研究采用酶联免疫分析方法，测定了分别灌胃给予50、100和200 mg/(kg bw·d)剂量的苯醚甲环唑玉米油溶液后，大鼠血清中孕酮(P)和雌二醇(E2)含量的变化，并在对大鼠卵巢进行苏木精-伊红(HE)染色后，通过光学显微镜观察统计了各级卵泡的数量。结果表明：苯醚甲环唑各剂量暴露组及对照组大鼠卵巢脏器系数均无显著性差异。200 mg/(kg bw·d)高剂量暴露组大鼠血清孕酮水平显著高于对照组(P <0.01),50和100 mg/(kg bw·d)剂量暴露组则与对照组无显著性差异，但均显著低于高剂量暴露组(P <0.05)；各剂量暴露组及对照组之间血清雌二醇水平均无显著性差异。从卵泡的发育情况看，200 mg/(kg bw·d)高剂量暴露组生长卵泡的占比显著高于对照组(P <0.05),50和100 mg/(kg bw·d)剂量暴露组则与对照组无显著性差异。研究表明，200 mg/(kg bw·d)剂量的苯醚甲环唑亚急性经...     

高效液相色谱-电喷雾质谱法测定土壤中的矮壮素残留

研究建立了土壤中矮壮素残留的高效液相色谱-电喷雾质谱(HPLC-ESI-MS)检测方法。样品经甲醇-乙酸铵水溶液提取、离心及浓缩后,经反相色谱柱分离,采用高效液相色谱-电喷雾质谱检测,在选择离子监测模式(SIM)下以碎片离子m/z 122.2进行外标法定量。土壤中矮壮素残留的检出限(S/N=3)为0.01 mg/kg,定量限为0.05 mg/kg;在0.01 ~1.0 mg/L范围内峰面积与质量浓度的线性关系良好(r2 ＞0.996)。在0.05、0.5和1.0 mg/kg 3个添加水平下,矮壮素的平均回收率范围为75.1% ~87.2%,相对标准偏差小于10%。对矮壮素在土壤中消解动态的研究结果表明,其在土壤中的消解半衰期为4.47 d。     

豆瓣菜中啶酰菌胺残留及膳食摄入风险评估

为评价啶酰菌胺在豆瓣菜生产上应用的安全性，采用QuEChERS方法进行样品前处理，液相色谱-串联质谱 (LC-MS/MS) 进行定量分析，检测了豆瓣菜中啶酰菌胺的最终残留量，对2种膳食食谱下的长期摄入风险进行了比较分析。结果表明，在添加水平范围内，在豆瓣菜空 白样品中添加啶酰菌胺的平均回收率为89%~100%，相对标准偏差为5%~12%。GAP条件下，最终残留量为0.16~37.1 mg/kg。普通人群啶酰菌胺的国家估计每日摄入量 (NEDI) 为1.215 1 mg/(kg bw)，风险商为48.2%，表明其对一般人群健康产生的风险是可接受的，同时，使用WHO提供的单独每种农产品膳食量进行计算，啶酰菌胺每日摄入量为0.083 0 mg/ (kg bw)，风险商为3.3%。经过对比分析，推荐使用WHO提供的膳食食谱数据进行长期膳食风险评估。     

高效液相色谱-串联质谱法研究哌虫啶在大鼠体内的吸收、分布及排泄

为阐明杀虫剂哌虫啶在SD大鼠体内的代谢动力学过程,以期为进一步的毒理学研究提供依据,采用所建立的高效液相色谱-串联质谱(HPLC-MS/MS)分析方法,测定了单次灌胃给药后大鼠血浆、组织(心、肝、脾、肺、肾、脑、骨骼肌、脂肪)、粪便和尿液样品中哌虫啶的含量,对该药在大鼠体内的吸收、分布和排泄进行了研究。结果表明:哌虫啶750 mg/kg单次经口灌胃给药,雌性大鼠血药浓度-时间曲线下面积(AUC)高于雄性大鼠,且达到峰值时间(T_(max))明显长于雄性大鼠,具有统计学差异,提示在此剂量下,哌虫啶在代谢及毒性效应上可能存在性别差异;在100~750 mg/kg受试剂量范围内,哌虫啶的平均半衰期为4~8 h,表观分布容积为10~30 L/kg,给药剂量与血药浓度-时间曲线下总面积(AUC_(0-inf))呈线性相关性(雄:r=0.996 4,雌:r=0.991 3)。组织分布试验表明,哌虫啶经口给药后,能迅速、广泛地分布到各组织中,并可有效地透过血脑屏障,其中肝、肾中哌虫啶的含量最高,提示其可能主要经肝、肾代谢。排泄试验显示,经尿液及粪便排出的原形哌虫啶含量极低,提示哌虫啶在大鼠体内可能发生广泛的代谢后再排出体外。     

高效氯氰菊酯对小鼠卵巢生殖功能的影响及维生素E的干预作用

为探究高效氯氰菊酯 (beta-cypermethrin, β-CP) 对雌性小鼠卵巢生殖功能的影响及维生素E (vitamin E, VE) 的干预作用,将雌性昆白小鼠随机分为6 组:空白对照组 (花生油处理)、β-CP不同剂量 (10、20、40 mg/kg) 处理组、VE保护组 (20 mg/kg β-CP+20 mg/kg VE) 和VE组 (20 mg/kg VE),连续灌胃10 d。灌胃结束后取小鼠卵巢组织,观察组织结构的病理变化,采用免疫组化法、蛋白免疫印迹试验及RT-PCR方法检测卵巢中StAR蛋白含量及casp-3、casp-8、INHα和INHβB 基因mRNA表达的变化。结果显示:与对照相比,10、20和40 mg/kg的β-CP处理均使小鼠卵巢组织结构发生了损伤,使组织中StAR蛋白的浓度分别降低了18.8%、36.3%和40.3%,casp-3基因的表达分别升高了16.0%、26.7%和52.9%,INHα基因的表达分别升高了34.5%、83.6%和228.7%,INHβB基因的表达分别升高了7.5%、39.2%和52.7%;20和40 mg/kg的β-CP处理使得casp-8基因的表达分别升高了27.1%和36.7%。上述处理组与对照组的差异均达显著水平 (P＜0.05)。与 20 mg/kg β-CP处理组相比,VE 保护组的StAR蛋白含量也显著增多 (P＜0.05)。研究表明,β-CP对小鼠卵巢具有毒性作用,这与β-CP抑制StAR蛋白的合成,上调casp-3、casp-8、INHα及INHβB基因的表达有关;添加VE对小鼠卵巢有一定的保护作用,这与VE可减弱β-CP对StAR蛋白合成的抑制作用有关。     

超高效液相色谱串联质谱法测定水中春雷霉素的含量

建立了水中春雷霉素含量的超高效液相色谱质谱联用测定方法。样品用SCX固相萃取小柱净化,以HPLC BEH HILIC色谱柱(2.1×50mm,1.7μm)分离,采用UPLC-MS/MS多反应监测(MRM)正离子模式测定,外标法定量。春雷霉素检出限为0.01mg/kg。在0.01、0.05、0.1mg/kg 3个浓度添加水平,回收率为86.4%～93.9%,相对标准偏差为2.5%~4.8%(n=5)。     

高效液相色谱-串联质谱法同时测定果蔬汁中9种农药残留

建立了高效液相色谱-串联质谱法(HPLC-MS/MS)同时检测果蔬汁中9种农药残留的检测分析方法。样品经乙腈提取,固相分散净化,采用高效液相色谱-串联质谱法进行测定。结果表明:9种农药在0.01 ~1mg/kg的范围内,质量浓度与相应的峰面积间呈良好的线性关系,相关系数均>0.99;9种农药在0. 01~1mg/kg添加水平下,平均添加回收率为70. 3%~105. 9%,相对标准偏差(RSD)为1.0%~11.5%(n=5);9种农药的定量限(LOQ)在0.01~0.05mg/kg之间。本方法快速、简便、净化效果好,且成本低,适用于9种农药在果蔬汁中的残留量检测。     

乙烯利对小鼠的免疫毒性研究

为了探讨乙烯利对人体健康的影响,选用溶血空斑试验、血清溶血素检测试验、迟发型变态反应试验和碳粒廓清试验,分别从体液免疫、细胞免疫和非特异性免疫功能等不同角度研究了乙烯利对小鼠的免疫毒性。结果表明,乙烯利67~268 mg/kg bw各剂量组的小鼠足跖肿胀程度、溶血空斑对数值以及半数溶血值均显著低于对照组(PPP<0.05)。结果提示,乙烯利对小鼠的免疫功能具有一定的抑制作用。     

三种有机磷农药胚胎期暴露对新生鼠脑组织结构的影响

探讨了3种常用的有机磷农药胚胎期暴露对新生鼠脑组织结构的影响。在母鼠妊娠期7.5～11.5 d时,连续5 d每天分别经皮下注射2 mg/kg bw的二嗪磷(diazinon)、2 mg/kg bw的毒死蜱(chlorpyrifos)及50 mg/kg bw乙酰甲胺磷(acephate),显微镜下观察并计数大脑皮层S1区胶质细胞和神经元数量及比率,以及海马CA1、CA3区锥体细胞的数量及体积密度。结果表明,二嗪磷与毒死蜱处理分别使得大脑皮层S1区胶质细胞数减少了14.29%和21.43%;毒死蜱处理导致胶质细胞与神经元比率下降了24.19%;二嗪磷与毒死蜱处理后海马CA1区锥体细胞数量分别下降了9.30％与20.93％,毒死蜱处理后锥体细胞体积密度下降了27.05％;二嗪磷与毒死蜱处理后海马CA3区锥体细胞数量分别下降了22.22％和19.44％,锥体细胞体积密度分别下降了23.54％和18.98％;而乙酰甲胺磷对新生鼠大脑皮层与海马细胞均无明显影响。     

The effects of Saw palmetto on flumethrin-induced lipid peroxidation in rats

In the present study, 40 male Wistar albino rats were used and divided into 4 groups. The first group served as the control group; the second group was administered Saw palmetto extract at the dose of 20 mg/kg/bw; the third group was administered flumethrin at the dose of 15 mg/kg/bw; and the fourth group was administered a combination of 20 mg/kg/bw Saw palmetto extract and 15 mg/kg/bw flumethrin, for 21 days, orally. After the trial period, blood and tissue (liver, kidney and brain) samples were taken from the rats. Saw palmetto extract did not cause significant alterations in plasma and tissue malondialdehyde (MDA) levels, serum and tissue nitric oxide (NO) levels, erythrocyte and tissue superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities when compared to the controls (p > 0.05). Flumethrin led to increased plasma and tissue MDA levels, serum and tissue NO levels, tissue GSH-Px activities and decreased erythrocyte and tissue SOD and CAT activities, and erythrocyte GSH-Px activity, compared to the controls (p < 0.05). The flumethrin and Saw palmetto extract combination increased erythrocyte SOD activity and decreased brain GSH-Px activity as compared to flumethrin (p < 0.05). In conclusion, it was determined that Saw palmetto extract did not cause any negative effect on the prooxidant-antioxidant balance. While flumethrin stimulated lipid peroxidation; Saw palmetto extract at the dose of 20 mg/kg/bw did not exhibit enough antioxidant effect in rats.     

Protective effect of vitamin C against chlorpyrifos oxidative stress in male mice

Pesticides may induce oxidative stress leading to generate free radicals and alternate antioxidant or oxygen free radical scavenging enzyme system. This study was conducted to investigate the acute toxicity of chlorpyrifos toward male mice and the oxidative stress of the sub-lethal dose (1/10 LD₅₀) on the lipid peroxidation level (LPO), reduced glutathione content (GSH) and antioxidant enzymes; catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glucose-6-phosphate dehydrogenase (G6PD), and glutathione-S-transferase (GST) activities. Also, the protective effects of vitamin C (200 mg/kg body weight, bw) 30 min before or after administration of chlorpyrifos were investigated. The results demonstrated that the LD₅₀ value of chlorpyrifos was 134.95 mg/kg bw. The oral administration of 13.495 mg/kg chlorpyrifos significantly caused elevation in LPO level and the activities of antioxidant enzymes including CAT, SOD and GST. However, GPx activity remained unchanged, while the level of GSH and G6PD activity were decreased. Vitamin C treatment to chlorpyrifos intoxicated mice decreased LPO level and GST activity, normalized CAT, SOD and G6PD activities, while GSH content was increased. We conclude that vitamin C significantly reduces chlorpyrifos-induced oxidative stress in mice liver and the protective effect of the pre-treatment with vitamin C is better than the post-treatment.     

Methyl parathion induced nephrotoxicity in male rats and protective role of vitamins C and E

Methyl parathion is an organophosphate insecticide that has been used in agriculture and domestic for several years. Vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day), methyl parathion (0.28 mg/kg bw per day) and vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day) + methyl parathion (0.28 mg/kg bw per day) combination were given to rats orally via gavage for 7 weeks. Body and kidney weights, malondialdehyde (MDA) levels and histopathological changes were investigated at the end of 4th and 7th weeks comparatively with control group. When methyl parathion-treated group and vitamins C and E + methyl parathion-treated group were compared to control group body and kidney weights decreased significantly at the end of 4th and 7th weeks. MDA levels increased in kidney tissues of the methyl parathion- and vitamins C and E + methyl parathion-treated groups compared to control group. MDA levels decreased significantly in vitamins C and E + methyl parathion treated group compared with methyl parathion treated group at the end of 4th and 7th weeks. In our light microscopic investigations, after 4 weeks of methyl parathion exposure, glomerular atrophy and vascular dilatation, and after 7 weeks, necrosis and edema were observed in the kidney tissues. After 4 weeks of vitamins C and E + methyl parathion exposure, mononuclear cell infiltrations, and after 7 weeks, calcification were detected in the kidney tissues.     

Evaluation of propolis effects on some biochemical parameters in rats treated with sodium fluoride

The present study in which 42 female rats, each weighing 200−250 g, were used covered a period of 21 days. The animals were divided into six groups. The first group served as the control group, whereas Group 2 was administered propolis at a dose of 200 mg/kg/bw in drinking water for 21 days. Group 3 was first provided with normal drinking water for a period of 14 days, and was subsequently administered propolis at a dose of 200 mg/kg/bw in drinking water for 7 days. Group 4 was first given normal drinking water for 14 days, and was secondly administered 100 ppm fluoride as a sodium fluoride in drinking water for 7 days. Group 5 was first administered propolis alone at a dose of 200 mg/kg/bw in drinking water for 14 days, and was secondly administered 100 ppm fluoride in association with 200 mg/kg/bw propolis for 7 days. Finally, Group 6 was first provided with normal drinking water for 14 days, and was secondly administered 100 ppm fluoride in association 200 mg/kg/bw propolis for a period of 7 days. At the end of the 21st day, blood samples were collected from the heart of each animal into both heparinised tubes and tubes without anticoagulants. Glucose, triglyceride, cholesterol, total protein, and uric acid levels, and aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) activities in the serum, as well as malondialdehyde (MDA) levels, glutathione peroxidase (GSH-Px) in the plasma, erythrocyte superoxide dismutase (SOD) and catalase (CAT) activities were measured. When compared to the control group, statistical differences were determined to exist with respect to oxidative stress parameters which involved increase in MDA levels in Groups 4−6, decrease in SOD activity in Groups 4 and 6, increase in CAT activity in Groups 5 and 6, and decrease in GSH-Px activity in Groups 4 and 6. Furthermore, in comparison to the control group, significant differences were observed with respect to certain serum biochemical parameters, including decrease in glucose levels in Groups 5 and 6, decrease in triglyceride levels in Groups 2 and 4, decrease in cholesterol levels in Groups 2 and 5, decrease in the total protein level of Groups 4−6, decrease in the ALT activity of Groups 5 and 6, increase in the AST activity of Group 4, decrease in the ALP activity of Groups 2−6 and increase in the uric acid level of Group 2. In the groups that were administered propolis in association with fluoride, improvement was observed in some oxidative stress parameters and certain other biochemical parameters. Changes determined in the oxidative stress parameters (especially MDA and SOD) were indicative of the anti-radical activity of propolis on the free radicals generated by sodium fluoride. However, the values not drawing completely close to those of the control group can be explained with propolis not being able to completely eliminate the free radicals and the other adverse effects generated by fluoride.     

Acute, subacute and subchronic administration of methyl parathion-induced testicular damage in male rats and protective role of vitamins C and E

Methyl parathion is an organophosphate insecticide that has been used in agriculture and domestic for several years. Vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day), methyl parathion (0.28 mg/kg bw per day) and vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day) + methyl parathion (0.28 mg/kg bw per day) combination were given to rats orally via gavage for 7 weeks. Body and testis weights, sperm counts, sperm motility, sperm morphology and histopathological changes in the testes were investigated at the end of 24 h, 4th and 7th weeks comparatively with control group. No pathological changes were observed in all parameters at the end of 24 h. When methyl parathion-treated group and vitamins C and E + methyl parathion-treated group were compared to control group, body and testis weights decreased significantly at the end of 4th and 7th weeks. It was observed that, at the end of 4th and 7th weeks there was a statistically significant decrease in sperm counts and sperm motility, increase in abnormal sperm morphology when methyl parathion- and vitamins C and E + methyl parathion-treated group were compared to control group. While sperm counts increased at the end of 4th and 7th weeks, sperm motility increased at the end of 7th week when vitamins C and E + methyl parathion-treated group compared with methyl parathion-treated group, no changes were observed in abnormal sperm morphology at the end of 4th and 7th weeks. In our light microscopic investigations, after 4 and 7 weeks of methyl parathion exposure, necrosis and edema were observed in the seminiferous tubules and interstitial tissues. After 4 and 7 weeks of vitamins C and E + methyl parathion exposure, degenerative changes were detected in the seminiferous tubules while no pathological findings were observed in the interstitial tissues. According to the present study, we conclude that vitamins C and E reduces methyl parathion testicular toxicity, but it does not protect completely.