It obtained from PCR.

Arsenic has been identified as an environmental toxicant acting through various mechanisms, including the disruption of endocrine pathways. The present study assessed the ability of a single intraperitoneal injection of arsenic, to modify the mRNA expression levels of estrogen- and thyroid hormone receptors (ERα,β; TRα,β) and peroxisome proliferator-activated receptor gamma (PPARγ) in hypothalamic tissue homogenates of prepubertal mice in vivo. Mitochondrial respiration (MRR) was also measured, and the corresponding mitochondrial ultrastructure was analyzed. Results show that ERα,β, and TRα expression was significantly increased by arsenic, in all concentrations examined. In contrast, TRβ and PPARγ remained unaffected after arsenic injection. Arsenic-induced dose-dependent changes in state 4 mitochondrial respiration (St4). Mitochondrial morphology was affected by arsenic in that the 5 mg dose increased the size but decreased the number of mitochondria in agouti-related protein- (AgRP), while increasing the size without affecting the number of mitochondria in pro-opiomelanocortin (POMC) neurons. Arsenic also increased the size of the mitochondrial matrix per host mitochondrion. Complex analysis of dose-dependent response patterns between receptor mRNA, mitochondrial morphology, and mitochondrial respiration in the neuroendocrine hypothalamus suggests that instant arsenic effects on receptor mRNAs may not be directly reflected in St3-4 values, however, mitochondrial dynamics is affected, which predicts more pronounced effects in hypothalamus-regulated homeostatic processes after long-term arsenic exposure.

砷已被认定为可通过多种机制发挥毒性作用的环境毒物，其中包括干扰内分泌通路。本研究通过体内实验，评估了单次腹腔注射砷对青春期前小鼠下丘脑组织匀浆中雌激素受体、甲状腺激素受体（ERα、β；TRα、β）以及过氧化物酶体增殖物激活受体γ（PPARγ）的mRNA表达水平的调控作用。同时检测了线粒体呼吸功能（mitochondrial respiration, MRR），并对相应的线粒体超微结构进行了分析。结果显示，在所检测的所有浓度下，砷可显著上调ERα、β及TRα的表达水平。与之相反，砷注射后TRβ与PPARγ的表达未受明显影响。砷暴露可引发状态4线粒体呼吸（state 4 mitochondrial respiration, St4）呈现剂量依赖性变化。砷可影响线粒体形态：5 mg剂量组中，刺豚鼠相关蛋白（agouti-related protein, AgRP）阳性神经元内的线粒体体积增大但数量减少；而阿黑皮素原（pro-opiomelanocortin, POMC）阳性神经元内的线粒体仅体积增大，数量未受影响。此外，砷还可使每个宿主线粒体的基质体积增大。对神经内分泌下丘脑中受体mRNA、线粒体形态与线粒体呼吸之间的剂量依赖性反应模式进行的综合分析表明：砷对受体mRNA的即时效应或许无法直接体现在状态3-4线粒体呼吸（state 3-4 mitochondrial respiration, St3-4）的检测值中，但线粒体动力学已受到影响，这预示着长期砷暴露后，下丘脑调控的稳态生理过程将出现更为显著的效应。