丰富环境对孕期慢性应激大鼠子代海马IGF-Ⅱ和NF-κB表达的干预研究  

Intervention of enriched environment on expressions of IGF-Ⅱand NF-κB in hippocampus of offspring of rats with chronic stress during pregnancy

作　　者：赵枫 刘志宏 付有娟 关素珍 ZHAO Feng;LIU Zhi-hong;FU You-juan;GUAN Su-zhen(School of Public Health and Management,Ningxia Medical University,Yinchuan,Ningxia 750004,China)

机构地区：[1]宁夏医科大学公共卫生与管理学院,宁夏银川750004

出　　处：《环境与职业医学》2020年第3期274-280,共7页Journal of Environmental and Occupational Medicine

基　　金：国家自然科学基金地区基金项目(81960591);宁夏自然科学基金项目(2018AAC02007);2019年宁夏医科大学优势学科群建设项目(3);宁夏回族自治区2019年大学生创新创业训练计划项目(S201910752018)。

摘　　要：[背景]生命早期生活环境对子代成长发挥着重要作用,孕期应激性事件会造成母体宫内环境改变,进而对子代生长发育产生影响。胰岛素样生长因子-Ⅱ(IGF-Ⅱ)和核因子-κB(NF-κB)蛋白主要分布在脑内与认知和情感记忆相关的区域,与单胺类神经递质去甲肾上腺素(NE)、多巴胺(DA)共同调节机体注意力和反应能力。丰富环境通过神经发生、突触发生、脑血管再生等神经重塑作用,在促进神经再生的同时可改善学习和记忆能力。[目的 ]探讨丰富环境干预对孕期慢性应激大鼠子代海马突触相关蛋白IGF-Ⅱ和NF-κB表达的影响。[方法 ]将20只Wistar雌鼠随机分为模型组和对照组,每组10只;15只Wistar雄鼠随机分为模型交配组10只和对照交配组5只。模型组选择慢性不可预知温和应激(CUMS)模型进行为期21 d的应激,在应激第3天按1∶1雌雄比例合笼;对照组于正常环境饲养,同期按2∶1雌雄比例合笼。雌鼠在应激前1d和应激第1、7、14天进行眼内眦静脉采血,利用放射免疫法测定血浆皮质醇质量浓度并计算皮质酮质量浓度。子鼠出生后21 d(PND21)断乳,将对照组的子鼠随机分为对照子鼠组和对照+丰富环境组,模型组的子鼠分为模型子鼠组和模型+丰富环境组,每组16只。进行丰富环境干预时,将子鼠每天暴露于丰富环境6 h(13:00-19:00),干预周期为30 d,未干预组于正常环境饲养。PND50时称重,并利用自制敞箱进行子鼠的行为学指标测定,指标包括水平运动得分和垂直运动得分。在PND55时处死各组子鼠,取海马组织。ELISA法检测子鼠海马组织单胺类神经递质NE和DA的水平,通过实时定量PCR和Western blotting法分别测定子鼠海马组织IGF-Ⅱ和NF-κB m RNA和蛋白的相对表达水平。[结果 ]模型组雌鼠在应激第7、14天血浆皮质酮质量浓度分别为[(348.50±13.24)和(258.38±22.77)μg·L^-1],均高于对照组雌鼠[(224.00±39.84)和(218.78±[Background] The early-life living environment plays an important role in the growth of offspring. Stressful events during pregnancy can induce changes in maternal intrauterine environment, which in turn affects the growth and development of offspring. Insulin like growth factor-Ⅱ(IGF-Ⅱ) and nuclear factor-κB(NF-κB) are mainly distributed in the areas related to cognition and emotional memory in the brain, they work together with monoamine neurotransmitters norepinephrine(NE) and dopamine(DA) to regulate the attention and response ability of the body. Enriched environment can improve learning and memory ability while promoting nerve regeneration through neurogenesis, synapsis, cerebrovascular regeneration and other neural remodeling effects.[Objective] This experiment is designed to investigate the effects of enriched environmental intervention on the expressions of hippocampal synapse-associated proteins such as IGF-Ⅱ and NF-κB in offspring of rats with chronic stress during pregnancy.[Methods] Twenty female Wistar rats were randomly divided into a model group and a control group of 10 rats each;15 male Wistar rats were randomly divided into a model group of 10 rats and a control group of 5 rats. The female rats of the model group received chronic unpredictable mild stress(CUMS) for 21 d, and were caged at a 1∶1 female-to-male ratio on the 3 rd day of the CUMS protocol. The female rats of the control group were reared in normal environment and caged at a 2∶1 ratio. Blood samples were collected from the iliac vein of the female rats 1 day before and 1, 7, and 14 days after the CUMS protocol, and measured for plasma cortisol content by radioimmunoassay to calculate corticosterone concentration. The offspring rats were weaned on postnatal day 21(PND21). The control offspring rats were randomly divided into a control offspring group and a control + enriched environment offspring group. The model offspring rats were divided into a model offspring group and a model + enriched environment offspring group,

关 键 词：丰富环境 胰岛素样生长因子-Ⅱ 核因子-κB 孕期慢性应激 去甲肾上腺素 多巴胺 

分 类 号：R114[医药卫生—卫生毒理学]