RNAi-induced change in the expression of estrogen receptor α in the median preoptic nuclei of mother rats and its effects on the behavior of their offsprings.

靶向异位基因沉默是研究激素/神经递质及其受体在大脑中的作用的宝贵方法。我们设计了一种策略，允许在体内局部转移siRNA或转染质粒DNA编码的shRNA内的正中视前核（POA）的rats.Injection的质粒DNA注射到下丘脑区域，包括成年雌性大鼠的POA，然后通过双极电极的电流的应用，导致在细胞内的DNA递送。我们使用编码EGFP的质粒DNA和三种针对雌激素受体α（ERα）的siRNA的混合物，发现EGFP在注射部位周围广泛表达。电穿孔后第4天，ERα阳性神经元数量减少，电穿孔后2周左右，注射部位周围ERα表达受到抑制。结果表明，该策略可用于功能获得或丧失实验。利用这种方法，我们确定了ERα在维持母性行为中的重要作用。因此，我们认识到，在体内电穿孔提供了一种新的方法来研究脑功能牵连在mother-pupils interactions.Craniofacial骨的大小和咬合在发育阶段的雄性SD大鼠在体内micro-CT检查。大部分3-13周龄的大鼠表现出后牙反咬，这是在体大鼠咬合的首次报道。将完全弗氏佐剂（CFA）注入大鼠颞下颌关节腔内，观察注射CFA后髁状突的骨质异常。我们的结论是，在体内微型CT是适合于检测小动物的骨结构的变化。

Targeted ectopic silencing of genes is an invaluable approach for studying the role of hormones/neurotransmitters and their receptor functions in the brain. We devised a strategy that allows localized in vivo transfer of siRNA or transfection of plasmid DNA encoding shRNA by electroporation within the median preoptic nuclei (POA) of rats.Injection of plasmid DNA into the hypothalamic areas including the POA of adult female rats, followed by application of electrical current via bipolar electrodes, resulted in intracellular delivery of DNA. We used a cocktail of plasmid DNA encoding EGFP and three siRNAs against estrogen receptor α (ERα), and found that EGFP was expressed widely at around the injection sites. With an examination of the brain sections obtained from the electroporated animals, we found that the number of ERα-positive neurons decreased at 4th day after the electroporation.Electroporation of plasmid DNA encoding shRNA against ERα caused suppression of the ERα expression for longer period (about 2 weeks) at around the injection sites. It was shown that this strategy could be used for gain-or loss-of-function experiments. Using this approach, we identified an essential role for ERα in maintaining the maternal behaviors. Thus, we recognized that in vivo electroporation provides a new approach to study the brain functions implicated in mother-pups interactions.Craniofacial bony sizes and occlusion during the developmental stage were examined in male SD rats by in vivo micro-CT. Most of the rats aged 3-13 weeks showed posterior cross bite, which was the first report of occlusion in rats in vivo. Complete Freund's adjuvant (CFA) was injected into the temporomandibular joint (TMJ) cavity of rats and osseous abnormalities in the condyle were observed after CFA injection. We conclude that in vivo micro-CT is suitable for detecting changes in the bone architecture of small animals.