Changes of expression of estrogen receptor ? in the paraventricular nucleus of mice during pregnancy and lactation / 第三军医大学学报

ABSTRACT

Objective To study the expression of estrogen receptor beta (ER ?) in the hypothalamic paraventricular nucleus (PVN) of maternal mice during pregnancy and lactation. Methods Nickel ammonium sulfate intensified immunocytochemical method was employed to investigate the expression of ER ? in the postnatal developing PVN of female mice. Results ER ? immunopositive materials were predominantly localized in the magnocellular division of PVN, and sparse positive cells were found in the parvocellular division. Most of the positive materials were found in the whole cell nuclei, but no obvious cytoplasma or process immunopositive cells were detected. In the pregnant female brain, generally, the ER ? level was lower. The lowest levels of expression were found at mid pregnancy, and then peaked at peripartum (from gestational days 18 to postpartum day 1), followed by another decrease to normal adult level from postpartum day 4. Conclusion The above results suggest that during pregnancy and lactation, ER ? may be predominantly involved in the PVN regulation of parturitional process.