生后雌性小鼠下丘脑室旁核内ER—β表达的免疫组化研究

研究发现小鼠下丘脑室旁核(PVN)内雌激素β受体(ER-β)的表达与在大鼠等一些实验动物脑PVN的表达有差异，提示其在小鼠PVN内的表达可能有特定的生理意义。为了深入探讨ER—β在小鼠PVN内的功能，本文采用硫酸镍铵增强显色的免疫组化SP法研究了ER—β在生后雌性小鼠PVN内的表达。结果发现ER—β免疫阳性物质主要见于PVN的大细胞部，在小细胞部和背侧帽部免疫阳性细胞数目较少。免疫阳性物质主要位于细胞核内，未发现明显的胞浆或突起阳性，但在发育的某些时期可见免疫阳性细胞核局部呈现阴性反应。最高表达见于生后早期(第1—9天)，随后表达降低，生后一个月即达到成年水平。PVN内ER-β的表达模式表现为生后早期表达高、随后降低，提示在该部位ER—β可能主要参与了对生后早期PVN的神经内分泌活动以及神经结构的发育与完善的调控，并可能与生后早期动物的应激、体重增加和脂肪代谢等有关。

Expression of estrogen receptor beta in the hypothalamic paraventricular nucleus of postnatal female mice]

Previous studies have revealed that estrogen receptor beta (ER-beta) in the mouse hypothalamic paraventricular nucleus (PVN) may play different roles from that in the PVN of rat and other animal species. In the present study, the expression of ER-beta in the developing PVN of postnatal female mice was studied using nickel ammonium sulfate intensified immunocytochemical techniques, and the results showed that ER-beta immunopositive materials were predominantly localized in the magnocellular division of the PVN, only sparse positive cells were found in the parvocellular division and dorsal cap of the PVN. Most of the positive cells were strongly labeled, but some lightly labeled cells were also detected. No apparent positive signals were observed in the cytoplasm or the processes of the neurons. The highest levels of expression were found at early postnatal days (postnatal day 1 to 9), and then it decreased to lower levels from day 15 and thereafter. The above results together with other findings suggest that at early postnatal development, ER-beta may play important role in the regulation of the structure and function of PVN, such as neuroendocrine, morphological maturation, food intake and body weight increase of postnatal animals.