胎生期・授乳期ビスフェノール A 曝露が生後の脳代謝に与える影響
演題番号 : P1-b21
溝川 拓一 / Hirokazu Mizokawa:1 國分 丈治 / George Kokubu:1 坂元 慎一 / Shinichi Sakamoto:1 金松 知幸 / Tomoyuki Kanamatsu:1
1:創価大学 工学部環境共生工学科 / Department of Environmental Engineering for Symbiosis, Soka university, Tokyo, Japan
Exposure to bisphenol A (BPA) during the gestation and lactation periods alters the locomotor activity and learning ability of mature rat offspring. The influences of BPA are caused through estrogen receptor. Estrogen is involved in organogenesis period of brain. The purpose of this study was to elucidate the effect of BPA on amino acid metabolism in the rat brain. The BPA-exposure groups were treated with 0.1, 1.0, and 5.0 ppm BPA in drinking water, respectively, and control group was given tap water. All weaning rats were kept giving the tap water. In this study, male offspring rats between 18 and 24 weeks of age were used. The rats were killed with the microwave treatment under anesthesia 20 min after the injection of [1-13C]glucose via the tail vein. Brain regions were dissected into frontal cortex, thalamus, striatum, hippocampus and brain stem according to the method of Glowinski and Iverson, then, the amino acid fraction was extracted from each tissue. The extracted fractions were analyzed by 13C-NMR spectroscopy. The 13C incorporation into GABA C2 from [1-13C]glucose was significantly lower in the thalamus and higher in the striatum in 0.1 ppm BPA-exposed group compared to the control group. In other brain regions, there was no significant difference in the 13C incorporation between four groups. In GABA concentration, there was no significant difference in the thalamus, and a significant increase was shown in the striatum. These results suggest that exposure to BPA during the gestation and lactation may affect GABA (inhibitory neurotransmitter) metabolism in the brain of offspring. An alteration of GABA metabolism may cause the behavioral abnormality in the rat offspring.