E2 and its alpha receptor (ERα) have an essential role in the regulation of maternal behavior. In dwarf hamster (Phodopus campbelli), E2 facilitates the display of paternal care, and it is possible that ERα is part of the neuroendocrine mechanisms that regulate this behavior. The aim of this study was to analyze the influence of copulation, cohabitation with the pregnant mate and the presence of the pups on paternal behavior, circulating E2 levels and the presence of ERα in the medial preoptic area (mPOA) and medial amygdala (MeA) in dwarf hamsters. Eight males were mated with intact females (IFs), 8 with tubally ligated females (TLFs) and 8 with ovariectomized females (OFs). In males mated with IFs, paternal behavior tests were performed after copulation, halfway through pregnancy and 24 h after the birth of their pups. Males mated with TLFs were subjected to paternal behavior tests at equivalent periods as the males mated with IFs. In males mated with OFs, paternal behavior tests were performed on days 1, 5 and 10 of cohabitation. After the last paternal behavior tests, blood samples were taken for quantification of E2 by radioimmunoassay (RIA), and the brains were dissected to determine ERα immunoreactivity (ir) in the mPOA and MeA. Fathers mated with IFs had higher serum E2 concentrations and more ERα-ir cells in the mPOA than those of males mated with TLFs and OFs. These results suggest that E2 and its ERα may be associated with paternity in the dwarf hamster.

中文翻译：

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矮仓鼠（Phodopus campbelli）父亲的mPOA和MeA中的雌二醇和雌激素受体α。

E2及其α受体（ERα）在调节孕产妇行为中起着至关重要的作用。在侏儒仓鼠（Phodopus campbelli）中，E2促进了父亲的照顾，而ERα可能是调节这种行为的神经内分泌机制的一部分。这项研究的目的是分析交配，与怀孕伴侣同居以及幼崽的存在对父亲行为，循环E2水平以及内侧视前区（mPOA）和杏仁核（MeA）的存在的影响。在侏儒仓鼠中。八只雄性与完整雌性（IFs）交配，八只与输卵管结扎雌性（TLFs）交配，八只与卵巢切除雌性（OFs）交配。在交配IF的雄性中，在交配后，妊娠中途和幼犬出生后24小时进行父亲行为测试。与TLF交配的雄性在与IF交配的雄性同等的时间接受父亲行为测试。在与OF交配的雄性中，在同居的第1、5和10天进行了父亲行为测试。在最后一次父亲行为测试之后，通过放射免疫分析（RIA）采集血样以定量E2，并解剖大脑以确定mPOA和MeA中的ERα免疫反应性（ir）。与IFS交配的父亲比与TLF和OFs交配的雄性具有更高的血清E2浓度和mPOA中更多的ERα-ir细胞。这些结果表明，E2及其ERα可能与矮仓鼠的亲子关系有关。在最后一次父亲行为测试之后，通过放射免疫分析（RIA）采集血样以定量E2，并解剖大脑以确定mPOA和MeA中的ERα免疫反应性（ir）。与IFS交配的父亲比与TLF和OFs交配的雄性具有更高的血清E2浓度和mPOA中更多的ERα-ir细胞。这些结果表明，E2及其ERα可能与矮仓鼠的亲子关系有关。在最后一次父亲行为测试之后，通过放射免疫分析（RIA）采集血样以定量E2，并解剖大脑以确定mPOA和MeA中的ERα免疫反应性（ir）。与IFS交配的父亲比与TLF和OFs交配的雄性具有更高的血清E2浓度和mPOA中更多的ERα-ir细胞。这些结果表明，E2及其ERα可能与矮仓鼠的亲子关系有关。