Lipopolysaccharide differentially alters systemic and brain glucocorticoid levels in neonatal and adult mice

We treated male and female C57BL/6J mice at postnatal day 5 (PND5) or PND90 with lipopolysaccharide (LPS; 50 µg/kg bw i.p.) or vehicle and collected blood and brain after 4 hr. We microdissected the prefrontal cortex, hippocampus, hypothalamus, and amygdala. We measured 7 steroids, including corticosterone, via liquid chromatography-tandem mass spectrometry and measured transcripts for key steroidogenic enzymes and hypothalamic-pituitary-adrenal axis components (Cyp11b1, Hsd11b1, Hsd11b2, Crh, Crhr1, Pomc) via qPCR.我们对出生后第5天（postnatal day 5, PND5）或出生后第90天（PND90）的雌雄C57BL/6J品系小鼠分别腹腔注射脂多糖（lipopolysaccharide, LPS；剂量为50 µg/kg体重）或溶剂对照，并于给药4小时后采集血液与脑组织。随后对前额叶皮层（prefrontal cortex）、海马体（hippocampus）、下丘脑（hypothalamus）及杏仁核（amygdala）进行显微解剖。我们采用液相色谱-串联质谱法（liquid chromatography-tandem mass spectrometry）检测了包括皮质酮（corticosterone）在内的7种类固醇激素，并通过实时定量聚合酶链式反应（quantitative polymerase chain reaction, qPCR）检测了关键类固醇生成酶及下丘脑-垂体-肾上腺轴（hypothalamic-pituitary-adrenal axis）相关组分（Cyp11b1、Hsd11b1、Hsd11b2、Crh、Crhr1、Pomc）的转录本水平。