Nakamura Keiko, Itoh Kyoko, Sugimoto Tohru, Fushiki Shinji
Department of Pathology and Applied Neurobiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto, Japan.
Neurosci Lett. 2007 Jun 13;420(2):100-5. doi: 10.1016/j.neulet.2007.02.093. Epub 2007 Mar 25.
Prenatal exposure to low-doses of bisphenol A (BPA) has been shown to affect murine neocortical development by accelerating neuronal differentiation/migration through disrupting thyroid hormone function. We therefore studied whether prenatal exposure to low-doses of BPA affected organization of adult neocortical structures. Pregnant mice were injected with 20 microg/kg of BPA daily from embryonic day 0.5 (E0.5) and bromodeoxyuridine (BrdU) was injected at E12.5, E14.5 and at E16.5, and the fetal brains were analyzed after birth. The BrdU-positive cells labeled at E14.5 were significantly increased in the Vth and VIth cortical layers of BPA-treated mice at postnatal 3 weeks (P3W), whereas they were confined to the IVth layer of control mice, though such differences disappeared at P12W. The thalamocortical projections demonstrated by DiI-labeling were abnormal at P3W and P12W in BPA-treated mice. These results indicate that BPA might affect not only neocortical development but also thalamocortical connections.
已表明产前暴露于低剂量双酚A（BPA）会通过破坏甲状腺激素功能加速神经元分化/迁移，从而影响小鼠新皮质发育。因此，我们研究了产前暴露于低剂量BPA是否会影响成年新皮质结构的组织。从胚胎第0.5天（E0.5）开始，每天给怀孕小鼠注射20微克/千克的BPA，并在E12.5、E14.5和E16.5时注射溴脱氧尿苷（BrdU），出生后对胎脑进行分析。在出生后3周（P3W）时，BPA处理组小鼠的第V层和第VI层皮质中在E14.5标记的BrdU阳性细胞显著增加，而在对照组小鼠中这些细胞局限于第IV层，不过这种差异在P12W时消失。用DiI标记显示的丘脑皮质投射在BPA处理组小鼠的P3W和P12W时异常。这些结果表明，BPA不仅可能影响新皮质发育，还可能影响丘脑皮质连接。
