Caffeine-induced fetal overexposure to maternal glucocorticoid and glucocorticoid metabolic activation in the fetal hippocampus.

<p>Pregnant rats ingested different doses of caffeine (20, 60, and 180 mg/kg) once per day from gestational day (GD) 11 to GD20. On GD20, the pregnant rats were anesthetized and sacrificed. The placenta and fetal serum prepared from blood samples were collected. The fetal hippocampuses were also dissected under an anatomy scope and collected. Placenta, fetal blood, and fetal hippocampus from each single pregnant rat were counted as one sample. (A, B) ELISA detection of the levels of maternal and fetal blood corticosterone (CORT). (C, D) Real-time quantitative RT-PCR and Western blotting detection of the mRNA and protein expression of the placental 11β-hydroxysteroid dehydrogenase 2 (11β-HSD-2). (E–K) Real-time quantitative RT-PCR and Western blotting detection of the mRNA and protein expression of the hippocampal 11β-HSD-2, 11β-hydroxysteroid dehydrogenase 1 (11β-HSD-1), and glucocorticoid receptor (GR). For real-time quantitative RT-PCR detection, each sample was normalized on the basis of GAPDH mRNA content. For Western blotting detection, the bar graphs represent the quantitative densitometric results of 11β-HSD-2, 11β-HSD-1 or GR protein expression; the intensity of each band of each sample was normalized on the basis of GAPDH protein content. Mean ± SEM, n = 8 pregnant rats. ^*<i>p</i><0.05, ^**<i>p</i><0.01 vs. control.