【摘要】 目的 观察长期低剂量邻苯二甲酸二(2-乙基己基)酯[di(2-ethylhexyl) phthalate, DEHP]暴露及高脂喂养对小鼠脑组织氨基酸类神经递质和神经元的影响。方法 选择体质量16～18 g SPF级雌性C57BL/6J小鼠，适应性喂养1周，随机分为对照组(Con组)、DEHP组(DEHP组)、高脂组(HFD组)、DEHP暴露联合HFD喂养组(HFD+DEHP组)。DEHP组和HFD+DEHP组小鼠经口给予50 μg/kg DEHP,Con组、HFD组小鼠给予等体积溶剂，Con组、DEHP小鼠喂饲普通维持饲料，HFD组、HFD+DEHP组小鼠喂饲高脂饲料。第24周末，每组随机取8只小鼠脱臼处死，取脑组织制备匀浆，并采用高效液相色谱法检测脑组织氨基酸类神经递质水平；每组剩余4只小鼠经体内灌注固定，制备大脑冰冻切片，采用尼氏染色观察神经元的变化。结果 HFD+DEHP组大脑皮层GABA高于Con组、DEHP组，HFD组、HFD+DEHP组Glu/GABA低于Con组(P<0.05);各组其他指标比较差异无统计学意义(P>0.05)。各组中脑中氨基酸类神经递质水平比较差异无统计学意义(P>0.05)。DEHP组、HFD组、HFD+DEHP组小脑Gly均高于Con组，HFD+DEHP组GABA高于Con组、DEHP组、HFD组(P<0.05);各组其他指标比较差异无统计学意义(P>0.05)。与Con组相比，DEHP组、HFD组及HFD+DEHP组小鼠大脑神经元中尼氏体颜色变淡、着色颗粒稀疏，以HFD+DEHP组最为明显。结论 DEHP长期暴露和高脂饮食可破坏小鼠脑内氨基酸类神经递质的内稳态，导致神经元损伤。更多还原

【Abstract】 Objective To observe the effects of long-term low-dose di(2-ethylhexyl) phthalate(DEHP) exposure and high-fat diet(HFD) on amino acid neurotransmitters and neurons in the brain of mice. Methods Female C57BL/6J mice weighing 16-18 g were housed at the SPF grade animal center for 1 week and randomly divided into control group(Con),DEHP group(DEHP),HFD group(HFD),and DEHP-HFD co-exposed group(HFD+DEHP).Mice of DEHP and HFD+DEHP group were orally exposed to 50 μg/kg DEHP,while mice of other groups were gavaged with equal volume of solvent.At the end of 24th weeks, 8 mice was randomly selected from each group and sacrificed by dislocation, brain tissues were collected, homogenized and followed by detection of amino acid neurotransmitters by high performance liquid chromatography(HPLC).The 4 remaining mice in each group were fixed via transcardiac perfusion with 4% paraformaldehyde, the brains were taken out for frozen sections.Then, the slices were performed Nissl staining to observe the changes of neuronal Nissl bodies. Results The brain cortex levels of GABA in mice co-treated DEHP and HFD were significantly higher than those of mice in Con and DEHP groups(P<0.05),the brain cortex Glu/GABA ratio of mice in the HFD and HFD+DEHP groups were lower than Con group(P<0.05);there was no statistically significant difference in the comparison of other indicators among different groups(P>0.05).The levels of all the amino acid neurotransmitters kept unchangeable in midbrain of mice among different groups.The cerebellar levels of Gly were significantly increased in the DEHP,HFD and HFD+DEHP treated mice compared with the control mice(P<0.05),and cerebellar GABA levels of mice from HFD+ DEHP group were obviously higher than those of mice in Con, DEHP and HFD groups(P<0.05);Other indicators had no significantly difference(P>0.05).The thionine staining showed that HFD and DEHP treatment led to lighter staining Nissl body, reduced density of colored granules, with the HFD+DEHP treated mice being the most pronounced. Conclusion Long-term exposure to DEHP at low dose and high-fat diet could disturb the homeostasis of amino acid neurotransmitters in the brain of mice and result in the neuronal damage and loss, which might partly attributed to the synergistic effects on central neurotoxicity between DEHP and HFD.更多还原