哺乳期母体接触氯氰菊酯对子代雌鼠学习记忆的损害效应

目的 研究哺乳期母鼠接触氯氰菊酯对子代成年雌鼠学习记忆能力的损害作用及其可能机制.方法 12只ICR母鼠随机分成对照组、6.25和25.00 mg/kg染毒组(每组4只母鼠,每窝10只仔鼠,雌雄各半,即每组20只雌鼠),于子代雌鼠出生后第1～21天(PNDl～ PND21),每天经口灌胃给予母鼠氯氰菊酯(6.25和25.00 mg/kg)染毒1次,对照组母鼠给予玉米油.染毒后39d,采用六臂放射状水迷 宫检测PND60雌鼠的学习记忆能力.检试结束后,称体重,处死动物取脑称重并分离海马组织,用蛋白质免疫印迹(Western blotting)法检测海马中N-甲基-D-门冬氨酸(NMDA)受体NR1亚单位蛋白表达水平.结果 各组子代雌鼠体重和脑重的差异无统计学意义(P＞0.05).经重复测量资料方差分析显示,在学习期,25.00 mg/kg染毒组子代雌鼠潜伏期[(31.3±17.0)s]长于对照组[(21.0±14.0)s];在记忆期,25.00 mg/kg染毒组子代雌鼠潜伏期[(24.6±21.1)s]较对照组[(14.1±16.3)s]延长,差异均有统计学意义(P＜0.05).各组子代雌鼠在学习期和记忆期的错误数比较,差异均无统计学(P＞0.05).与对照组相比,25.0 mg/kg染毒组子代雌鼠海马组织NR1蛋白表达水平明显降低,差异有统计学意义(P＜0.01).结论 哺乳期母鼠接触氯氰菊酯在一定程度上损伤子代成年雌鼠学习记忆能力,可能与海马组织中NR1亚单位蛋白表达水平下降有关.     

甲醛染毒对大鼠子代神经行为发育的影响

[目的]探讨甲醛对大鼠子代早期神经行为发育的影响。[方法]进行两代一窝繁殖试验,选用体重110-130 g Wistar大鼠120只,随机分为4组,染毒浓度分别为,高浓度组:(119.6±15.4)mg/m3、中浓度组:(25.2±4.6)mg/m3、低浓度组:(4.8±1.3)mg/m3、对照组:室内空气。采用静式吸入法,每天染毒1 h,雄鼠连续染毒至交配后,雌鼠连续染毒至子代断乳,用一组行为毒理学方法检测雌、雄大鼠暴露于甲醛后子代生理及神经行为发育的情况。[结果]随着染毒浓度的增加,F1、F2代大鼠张耳、门齿萌出和开眼3项反映早期生理发育指标和平面翻正反射和悬崖回避试验阳性率呈逐渐降低趋势(P<0.05),学习、记忆达标训练次数和达标时间明显增多和延长(P<0.05),高浓度组学习达标时间、记忆达标时间分别高达(307.0±49.5)s、(279.7±42.35)s,持续游泳时间及耐缺氧时间均逐渐缩短,分别为(31.63±7.50)min、(43.40±4.94)min,P<0.05。[结论]甲醛对子代大鼠的神经系统有明显的损害作用。     

低铅染毒对大鼠子代神经行为发育的影响

本实验选用Ｗｉｓｔａｒ大鼠，采用醋酸铅经口饲喂染毒，观察了低浓度铅对大鼠子代神经行为发育的影响。结果显示：各染毒组仔鼠的体格发育，早期生理发育，行为发育均明显落后于对照组（Ｐ＜００５，Ｐ＜００１）；学习和记忆能力也显著减退。结果提示，低浓度铅接触仍能影响子代中枢神经系统的发育，导致其神经行为功能的异常     

经胎盘暴露壬基酚对仔鼠神经行为发育的影响

目的 探讨母体壬基酚(NP)暴露对子代大鼠神经行为发育的影响.方法 将确定受孕的SD大鼠随机分为对照组及50、100、200 mg/kg NP组,每组6或7只,妊娠第9-15 d灌胃NP.观察NP对仔鼠生理发育、神经行为发育的影响;于出生后1、7、14、21、28 d测体重,脱椎取大脑海马组织行HE染色,光学显微镜下观察其病理变化.结果 200 mg/kg NP剂量组仔鼠早期生理发育指标张耳、长毛、出牙、开眼时间分别为(4.5±0.8)、(5.2±0.8)、(12.7±1.4)、(16.0±7.7)d,较对照组[(3.6±0.5)、(3.6±0.5)、(11.1±1.1)、(12.7±1.3)d]明显延长,差异有统计学意义(p<0.05),200mg/kgNP剂量组仔鼠的断崖回避、平面翻正、空中翻正、负趋地性、听觉惊愕和视觉定向发育时间分别为(9.8±1.0)、(6.5±0.8)、(11.3±0.5)、(9.2±o.8)、(11.2±1.0)、(20.2±1.0)d,比对照组[(8.0±0.6)、(5.1±0.4)、(8.3±0.5)、(9.2±0.8)、(9.3±0.5)、(9.3±0.5)d]明显延长,差异有统计学意义(P<0.05或P<0.01).100 mg/kg NP剂量组仔鼠平面翻正、断崖回避、视觉定向时间均比对照组明显延长,差异有统计学意K(P<0.05或P<0.01).病理学检查可见100、200 mg/kg NP组海马组织充血水肿.结论 NP宫内暴露可影响仔鼠神经行为的发育.     

太原市和长治市孕妇多环芳烃暴露与新生儿神经行为发育的研究

目的 分析太原市和长治市空气中多环芳烃的含量和新生儿神经行为发育检查(NBNA)得分,探讨孕妇呼吸含多环芳烃的空气对新生儿神经行为发育的影响.方法 应用高效液相色谱法测定2009年11月至2010年5月长治市和太原市合作医院空气中多环芳烃含量、同期在合作医院生产的297名孕妇的尿中1-羟基芘含量,应用NBNA法测定新生儿神经行为发育情况,对两地空气中多环芳烃含量、孕妇尿中1-羟基芘含量和NBNA得分进行比较.结果 太原市和长治市空气中芘、苯并[a]蒽、屈、苯并[a]芘、二苯并蒽含量的差异有统计学意义(P＜0.10).太原合作医院孕妇的尿中1-羟基芘含量中位数为1.140 μg/mmol Cr(P5为0.457 μg/mmol Cr,P75为2.678 μg/mmol Cr),长治合作医院孕妇的尿中1-羟基芘含量中位数为0.761 μg/mmol Cr(P25为0.133 μg/mmol Cr,P75为2.095 μg/mmol Cr),两地合作医院孕妇尿中1-羟基芘含量的差异有统计学意义(t=-3.140,P=0.002).太原市和长治市新生儿NBNA总分、行为能力得分、被动肌张力得分、主动肌张力得分和一般估价得分比较,差异有统计学意义(P＜0.10).NBNA得分及单项得分与孕妇尿中1-羟基芘含量有负相关关系.结论 妇女孕期呼吸含多环芳烃的空气对新生儿神经行为发育有不良影响.     

孕期暴露苯并[a]芘对子代大鼠神经发育毒性的影响

目的 研究孕期暴露苯并(a)芘(B[a]P)对子代大鼠生理发育、早期行为发育、对环境的适应能力及学习记忆能力的影响.方法 SD孕鼠随机分为未处理对照组(每日正常饲养)、溶剂对照组(橄榄油)、低剂量组(25mg/kgB[a]P)、中剂量组(50mg/kgB[a]P)、高剂量组(100mg/kg B[a]P),于妊娠第17天开始,每天1次腹腔注射染毒,连续3 d,待其自然分娩.仔鼠出生后第1、4、7、14、28天称量体重,检测仔鼠生理发育、运动反射及感觉功能等发育指标,用Morris水迷宫试验和旷场试验分别评价仔鼠的学习记忆能力和对新异环境的适应能力.结果 与未处理对照组[(3.3±0.5)d]和溶剂对照组[(3.4±0.6)d]比较,中、高剂量组仔鼠张耳时间[(4.1±0.4)、(5.0±0.4)d]延长,差异有统计学意义(P＜0.01).与未处理对照组(36、1%)相比,第4天高剂量组平面翻正试验达标率(6.5%)明显降低,与未处理对照组和溶剂对照组(81.3%、79.3%)相比,第7天时高剂量组仔鼠平面翻正试验达标率(50.0%)明显降低,差异有统计学意义(P＜0.05).与未处理对照组比较,第12、14天时各染毒组仔鼠前肢悬挂时间均减少;与溶剂对照组比较,第14天时高剂量组仔鼠前肢悬挂时间减少,差异有统计学意义(P＜0.01).与未处理对照组(94.3%)相比,第12天时高剂量组仔鼠嗅觉定向试验达标率(61.9%)明显降低,差异有统计学意义(P＜0.05).Morris水迷宫试验结果表明,与未处理对照组和溶剂对照组比较,各剂量组仔鼠逃避潜伏期明显增加,高剂量组在目标象限停留时间和穿越平台次数减少,差异均有统计学意义(P＜0.01).旷场实验结果表明,与未处理对照组[(2.40±0.89)、(82.2±15.9)、(17.4±3.9)s]比较,中、高剂量组仔鼠中央格停留时间[(9.67±1.53)、(12.80±3.77)s]明显延长,跨格次数(51.3±8.7、49.4±20.0)明显减少,高剂量组直立次数(8.0±2.6)明显减少,差异均有统计学意义(P＜0.05);与溶剂对照组相比,各剂量组跨格次数明显减少,差异均有统计学意义(P＜0.01,P＜0.05).结论 孕期暴露B[a]P对仔鼠的生理发育、早期行为发育产生一定的抑制作用,并对仔鼠大脑学习记忆能力及其对新异环境的适应能力有一定影响.

Abstract：

Objective To study the effects of prenatal exposure to benzo[a]pyrene (B[a]P) on the physical development, early behavioral development, the adaptability to new environment and the learning and memory ability of rat offspring. Methods Pregnant rats were randomly divided into five groups: control group,olive oil group, 3 exposure groups (25, 50 and 100 mg/kg B [a]P). The rats were exposed to B [a]P) by intraperitoneal injection on the 17th-19th days during gestation. The offspring were weighed on postnatal days (PND)1, PND 4, PND 7 and PND 28, the indices of physical development, reflective ability and sensory function were detected for offspring, the Morris water maze and Open-field tests were used to measure the ability of learning and memory and the adaptability to new environment of offspring. Results The time of ear opening in middle and high-dose groups[(4. 1 ±0.4),(5.0±0.4) d] was posterior to that in untreated and solvent groups[(3.3±0.5),(3.4±0.6) d](P＜0.01).The attainment rate (6.5%) of the surface righting reflex test in highdose group on the 4th day was significantly lower than that (36.1%) in untreated group, the attainment rate(50.0%) in high-dose group on PND7 was significantly lower than those (81.3% and 79.3%) in untreated group and solvent group (P＜0.05). Compared to the untreated group, the time of forelimb hanging test in all exposure groups on PND12 and PND14 significantly decreased; compared to the solvent group the time of forelimb hanging test decreased in high-dose group on the 14th day significantly decreased (P＜0.01). The attainment rate (61.9%) of olfactory discrimination in high-dose group on PND 12 was significantly lower than that (94.3%) in untreated group (P＜0.05). The results of morris water maze test showed that the escape latency of different dose groups significantly increased, and the time of spatial probe and the times of traversing flat in high-dose group decreased significantly, as compared to the untreated and solvent groups(P＜0.01). The results of open-field test indicated that the center retention time in middle and high-dose groups significantly prolonged, the times of crossing lattice obviously reduced, and the rearing times decreased in high-dose group,as compared to untreated(P＜0.05).Compared to the solvent group, the times of crossing lattice in all exposure groups reduced significantly(P＜0.01 or P＜0.05). Conclusion The prenatal exposure to B[a]P could inhibit the physical development and early behavioral development, and influence the adaptability to new environment and learning and memory ability for offspring.     

职业性接触氰戊菊酯农药对工人心血管及神经系统的影响

目的　探讨职业性接触氰戊菊酯农药对工人心血管及神经系统的影响,保护工人身体健康。方法　分别选择某农药厂工龄半年以上的氰戊菊酯生产工人61名为暴露组,厂行政办公区工作人员10 2名为对照组。对两组环境空气中氰戊菊酯及其相关溶剂如甲苯、二甲苯进行连续3d的监测,同时选择暴露区及对照区各3人进行连续3d的个体采样测定,评价暴露水平;按统一的实施标准对他们的一般情况、心血管系统(血压、心电图)、神经系统进行健康检查。结果　暴露组空气中氰戊菊酯浓度明显高于对照组(P <0 0 1) ,而甲苯、二甲苯两组间差异无显著性(P >0 0 5 ) ,同时个体采样和皮肤污染量结果均显示暴露组氰戊菊酯浓度显著高于对照组(P <0 0 1) ;暴露组舒张压异常率显著高于对照组(P <0 0 5 )。结论　职业性接触氰戊菊酯农药对工人心血管系统有一定的影响,未发现对神经系统有影响     

氟-砷联合染毒对大鼠子代神经行为发育的影响

为揭示氟－砷共存对子代健康的影响,采用两代一窝繁殖的实验方法,测定Ｗｉｓｔａｒ大鼠暴露于氟、砷后其子代神经行为发育的情况。结果显示：随染毒剂量的增加,早期生理发育指标阳性率和早期神经反射阳性率逐渐减少,各染毒组仔鼠学习及记忆能力显著降低,游泳时间和耐缺氧时间逐渐缩短。电镜观察可见脑组织有明显病变,表现为神经细胞数量减少,核形态不规则,细胞器病变,突触数量显著减少。说明氟－砷对子代的神经系统有明显的损害作用,综合分析这些变化对早期发现氟－砷对子代的不良影响具有实际意义     

孕期暴露苯并[a]芘对子代大鼠神经发育毒性的影响

Objective To study the effects of prenatal exposure to benzo[a]pyrene (B[a]P) on the physical development, early behavioral development, the adaptability to new environment and the learning and memory ability of rat offspring. Methods Pregnant rats were randomly divided into five groups: control group,olive oil group, 3 exposure groups (25, 50 and 100 mg/kg B [a]P). The rats were exposed to B [a]P) by intraperitoneal injection on the 17th-19th days during gestation. The offspring were weighed on postnatal days (PND)1, PND 4, PND 7 and PND 28, the indices of physical development, reflective ability and sensory function were detected for offspring, the Morris water maze and Open-field tests were used to measure the ability of learning and memory and the adaptability to new environment of offspring. Results The time of ear opening in middle and high-dose groups[(4. 1 ±0.4),(5.0±0.4) d] was posterior to that in untreated and solvent groups[(3.3±0.5),(3.4±0.6) d](P＜0.01).The attainment rate (6.5%) of the surface righting reflex test in highdose group on the 4th day was significantly lower than that (36.1%) in untreated group, the attainment rate(50.0%) in high-dose group on PND7 was significantly lower than those (81.3% and 79.3%) in untreated group and solvent group (P＜0.05). Compared to the untreated group, the time of forelimb hanging test in all exposure groups on PND12 and PND14 significantly decreased; compared to the solvent group the time of forelimb hanging test decreased in high-dose group on the 14th day significantly decreased (P＜0.01). The attainment rate (61.9%) of olfactory discrimination in high-dose group on PND 12 was significantly lower than that (94.3%) in untreated group (P＜0.05). The results of morris water maze test showed that the escape latency of different dose groups significantly increased, and the time of spatial probe and the times of traversing flat in high-dose group decreased significantly, as compared to the untreated and solvent groups(P＜0.01). The results of open-field test indicated that the center retention time in middle and high-dose groups significantly prolonged, the times of crossing lattice obviously reduced, and the rearing times decreased in high-dose group,as compared to untreated(P＜0.05).Compared to the solvent group, the times of crossing lattice in all exposure groups reduced significantly(P＜0.01 or P＜0.05). Conclusion The prenatal exposure to B[a]P could inhibit the physical development and early behavioral development, and influence the adaptability to new environment and learning and memory ability for offspring.     

促进婴幼儿神经行为发育的优化模式研究

【目的】探讨促进婴幼儿神经行为发育的优化模式,以便临床有效指导。【方法】将180例生后28 d的正常足月婴儿分为优化组(孕期保健+常规儿童保健+早期发展指导)、常规组(常规儿童保健)和单一组(定期预防接种)。婴儿生后28 d,进行问卷调查、体格检查和新生儿20项神经行为评定。婴儿生后6、12、18和24个月,进行体格检查、血液学检测和Gesell发育诊断量表测试。【结果】优化组神经行为发育商数最高(116.75±7.69),常规组次之(99.52±10.11),单一组最低(93.61±11.42);优化组与单一组比较差异具有高度统计学意义(t=28.341,P0.01)。【结论】常规儿童保健与早期发展指导和孕期保健相结合,是促进婴幼儿神经行为发育的最佳模式。     

西维因与氰戊菊酯联合染毒对大鼠肝脏脂质过氧化的影响

目的探讨西维因与氰戊菊酯联合染毒对大鼠肝脏脂质过氧化作用的影响。方法将80只健康成年清洁级SD大鼠按2×2析因设计随机分为4组,分别为阴性对照(玉米油)组、西维因单独染毒组(1/50 LD_(50),11.2 mg/kg)、氰戊菊酯单独染毒组(1/50 LD_(50),9.02 mg/kg)和西维因(11.2 mg/kg)+氰戊菊酯(9.02 mg/kg)染毒组,每组20只,雌雄各半。采用经口灌胃方式进行染毒,每天1次,每周6天,连续染毒8周。末次染毒24 h后,测量大鼠肝组织中超氧化物歧化酶(SOD)、谷胱甘肽S转移酶(GST)活力和还原性谷胱甘肽(GSH)、丙二醛(MDA)含量。结果西维因和氰戊菊酯联合染毒使雄鼠肝脏中SOD活力下降(P0.05)、MDA含量升高(P0.05),雌鼠肝脏中GSH含量下降(P0.05),交互效应均有统计学意义,对SOD、GSH表现为拮抗作用,对MDA表现为协同作用;其它指标交互作用均无统计学意义(P0.05)。结论西维因和氰戊菊酯联合染毒对大鼠肝脏存在联合毒性作用,可能是通过破坏氧化-抗氧化系统的平衡,产生氧化损伤作用。     

Effects of fenvalerate exposure on semen quality among occupational workers

Purpose

The purpose of the study was to observe the effects of fenvalerate exposure on the semen quality of occupational workers.

Materials and Methods

Thirty-two male workers who were exposed to fenvalerate and 46 male administrators in the office in the same pesticide factory were selected as the exposure group and internal control group, respectively, and 22 male administrators in a center for disease control served as the external control group. In order to evaluate the exposure levels, the concentration of fenvalerate, toluene and xylene in the ambient air of the work place in these three groups were monitored simultaneously for 3 consecutive days. Moreover, the amount of fenvalerate in individual sampling and dermal contamination were evaluated in the exposure group and external control group. After the semen was collected according to the standard method, the workers' semen qualities were analyzed.

Results

Concentration of fenvalerate in the exposure areas was 21.55×10⁻⁴ mg/m³. The fenvalerate concentration in individual samplings in the exposure areas was 0.11 mg/m³. The dermal contamination for workers in the fenvalerate exposure area was 0.05 mg/m³. Fenvalerate was not detected in individual samplings collected in external areas. Sperm motion parameters through routine semen analysis in the exposure group were decreased significantly, and the abnormality rate of viscidity and coagulation was increased significantly as compared with the internal and the external control groups (p<.05 or p<.01). Furthermore, sperm progression and beat cross frequency (BCF) (4.20±1.68 Hz) in the exposure group were also significantly lower than those in the external control group by computer-assisted sperm motility analysis (CASA) (p<.05).

Conclusion

Occupational exposure to fenvalerate could affect the semen quality of the workers, but the conclusion warrants further complete investigation due to various limitations of the study.     

邻苯二甲酸酯母体暴露对子代影响的研究进展

随着工业的快速发展,邻苯二甲酸酯在全球范围内得到了广泛运用,在一定程度上增加了邻苯二甲酸酯的暴露机会,可对人体健康产生多种危害。该文综述了国内外关于邻苯二甲酸酯母体暴露影响子代生长发育、生殖发育、神经行为、肾脏发育及心肌的相关研究。     

围生期双酚A暴露对大鼠子代行为发育的影响

目的研究围生期暴露于双酚A对SD大鼠子代的行为发育的影响。方法 120只孕鼠随机分为6组,每组20只。从孕期d 6至仔鼠出生d 21断乳每天分别灌胃给予0、0.05、0.5、5、50、500mg/kg的双酚A。于仔鼠出生后d 3检测前、后肢定位反射;出生后4 d检测仔鼠的平面翻正、悬崖回避反射;出生后d 5检测负向地性;出生后d 11检测空中翻正反射。结果 0.05、0.5mg/kg剂量组的所有的神经反射均与对照组无明显差异,5mg/kg剂量组的平面翻正反射、负向地性反射、空中翻正反射达标天数与对照组相比显著延迟;50mg/kg剂量组,在前、后肢定位反射、空中翻正反射达标天数与对照组相比显著延迟;500mg/kg剂量组,在前、后肢定位反射、负向地性反射、空中翻正反射以及悬崖回避反射的达标天数与对照组相比显著延迟。结论大鼠围生期暴露于双酚A,可影响子代大鼠的神经行为发育。     

Protein malnutrition during pregnancy alters maternal behavior and anxiety-like behavior in offspring

Objective: The aim of this study was to evaluate the effects of protein malnutrition during pregnancy on maternal behavior, on the early behavior in pups by ultrasonic vocalizations (USVs) emission, and on the behavior of offspring in adulthood in an elevated T-maze.

Methods: Pregnant female rats were fed a normal protein-powdered diet (22% casein; control) or a low-protein (hypoproteic) diet (6% casein; protein restriction) during the first 2 weeks of pregnancy. On the fifth postpartum day (PND5), the number of USV was rated. On PND7, maternal behavior was assessed. Male offspring in adulthood were evaluated for behavioral performance in an elevated T-maze.

Results: Our results demonstrated that a hypoproteic diet during early pregnancy increased the maternal behavior, increased the number of USV by pups, and reduced the inhibitory avoidance responses in an elevated T-maze during adulthood. In addition, there was a reduction in weight gain of rats during pregnancy and of offspring during lactation.

Conclusion: In conclusion, the data found in our study suggest that the increase in USV emitted by pups due to hypoproteic diet during pregnancy accentuated maternal behavior. In addition, an increase in maternal care promoted the reduction in anxiety-like behavior in adult male offspring.     

甲基汞暴露对子代生长发育的影响——基于DNA甲基化研究

目的 本研究基于DNA甲基化,探讨甲基汞（Me Hg）暴露对子代生长发育的影响。方法 通过面对面问卷调查获取研究对象基本信息,系统采集万山汞矿区114位分娩母亲的静脉血、新生儿脐带血和生长发育指标。将24只妊娠SD大鼠随机分为对照组（生理盐水）、低（0.6 mg/kg）、中（1.2 mg/kg）、高（2.4 mg/kg）剂量Me Hg染毒组,自受孕第5天灌胃染毒至子代仔鼠出生第21天（PND21）,适应性喂养至PND60天。利用液相色谱-串联质谱法测量新生儿脐带血和仔鼠血5-甲基胞嘧啶（5m C）和5-羟甲基胞嘧啶（5hm C）水平。结果 暴露组新生儿的体重（t=2.025,P=0.045）和双顶径（t=2.382,P=0.019）均显著低于对照组。与对照组相比,暴露组脐带血5m C(t=2.615,P=0.010)和5hm C(t=3.640,P<0.001)均显著下降。脐带血5m C与新生儿股骨长之间呈显著正相关（r=0.197,P=0.035）。动物实验结果显示,各剂量染毒组仔鼠体重组间差异有统计学意义（F=11.327,P<0.001）;与对照组相比,低、中、高剂量...     

子宫内铅暴露对仔鼠牙齿萌出和釉质发育的影响

目的观察母鼠妊娠期间不同剂量铅暴露对仔鼠牙齿萌出情况和釉质发育的影响。方法27只怀孕SD大鼠随机分为铅暴露高剂量组、低剂量组和对照组,每组9只。铅暴露组饮用去离子水中加入醋酸铅进行染毒[以铅(Pb2+)含量计算高剂量组200mg/L、低剂量组50mg/L],对照组饮用去离子水。染毒自大鼠孕第1天持续至自然分娩。仔鼠出生后第26天在下切牙龈乳头水平进行第1次标记,并于出生后第36天在同一牙龈乳头水平行二次标记。第2次标记当日取全血测定血铅并处死仔鼠。测定切牙铅含量,应用立体显微镜观察牙齿形态并测量切牙两次标记间距离,应用电子探针测定切牙釉质钙、磷含量并计算比值。结果高、低剂量铅暴露仔鼠组血铅较对照仔鼠组增高,差异有统计学意义(P<0.01);高、低剂量铅暴露仔鼠组齿铅[(77.3±6.3)、(27.8±4.5)μg/g]与对照仔鼠组[(6.6±0.8)μg/g]相比,差异有统计学意义(P<0.01)。铅暴露仔鼠组切牙较小,牙尖磨耗明显并多见舌侧髓腔暴露,高铅剂量组更为明显。高、低剂量铅暴露仔鼠组切牙萌出速率[(0.25±0.08)、(0.30±0.09)mm/d]与对照仔鼠组[(0.39±0.09)mm/d]比较,铅暴露组萌出较为缓慢,三组间差异有统计学意义(P<0.01)。仔鼠釉质钙/磷比分析显示,随铅染毒剂量的增加,钙/磷比(1.68±0.54、1.37±0.47)降低,     

Effects of perinatal exposure to bisphenol A on brain neurotransmitters in female rat offspring

Pregnant Sprague-Dawley (CD IGS) rats were orally administered doses of bisphenol A (BPA) at 4, 40, and 400 mg/kg, from gestation days 6 to postnatal day 20. Neurotransmitters such as dopamine (DA) and serotonin (5HT) were extracted from the brains of dams and female offspring, and measured using liquid chromatography. BPA at 400 mg/kg was toxic and dosed rats died. At 3 wk after birth, brain levels of 3,4-dihydroxyphenylacetic acid (DOPAC, a DA metabolite), homovanillic acid (HVA, a DA metabolite), 5HT, 5-hydroxyindoleacetic acid (5HIAA, a 5HT metabolite) in female offspring were increased and the HVA/DA ratio was high in some brain areas of BPA-treated groups as compared with controls. At the age of 6 wk, levels of choline (Ch) in BPA-treated groups at 4 and 40 mg/kg were higher than control in all of eight brain areas. No changes were observed in acetylcholine (ACh) contents. In 9-wk-old offspring, changes in monoamines and metabolites were scattered and not great. At 3 wk after delivery, levels of 5HIAA in some brain areas of dams treated with BPA were higher than in control dams. Dose dependent increases in HVA and the HVA/DA ratio of the occipital cortex, and in the HVA/DA ratio of the frontal cortex were observed. The turnover of DA and 5HT was accelerated in 3-wk-old offspring and dams. BPA possesses very weak estrogenic activity. Changes in cerebral neurotransmitters observed in offspring and dams in this study may have been related to the estrogenic activity of BPA. However, further investigation is needed to examine the contribution of hormonal activity to such neurotransmitter changes.