Effects of gestational iron deficiency on fear conditioning in juvenile and adult rats
Effects of gestational iron deficiency on fear conditioning in juvenile and adult rats
复制标题
DOI：
10.1016/j.brainres.2008.08.079
复制
发表时间：
2008-10-27
期刊：
影响因子：
2.9
通讯作者：
Georgieff, Michael K.
中科院分区：
文献类型：
--
作者：
Gewirtz, Jonathan C.;Hamilton, Kathryn L.;Georgieff, Michael K.
海马体对妊娠期和新生儿缺铁的影响特别敏感，即使在补充铁后也是如此。这项研究比较了从妊娠第 2 天到产后第 7 天持续缺铁对“延迟”和“追踪”恐惧调节的影响。只有后一种范式严重依赖于背侧海马体。在不同组的大鼠中，恐惧条件作用开始于青春期之前（P28或P35）或青春期之后（P56）。恐惧调节是通过恐惧增强惊吓来测量的。 P28 和 P35 时，延迟和微量恐惧条件反射均因缺铁而减弱。在缺铁组中，可塑性相关蛋白 PKC-gamma 的海马表达通过微量恐惧调节而增加，但在 P35 时减少。 P56 组中先前缺铁会增强微量恐惧条件反射。在铁充足的成年人中的这一意外发现与发育性缺铁对抑制性回避学习的影响一致，但与更严重的缺铁方案的持续有害长期影响形成鲜明对比，表明缺铁的程度和持续时间会影响从其有害影响中恢复的可能性。 (c) 2008 Elsevier B.V. 保留所有权利。
The hippocampus is especially sensitive to the effects of gestational and neonatal iron deficiency, even after iron repletion. This study compared the effects of iron deficiency, maintained from gestational day 2 to postnatal day (P)7, on "delay" and "trace" fear conditioning. Only the latter paradigm is critically dependent on the dorsal hippocampus. In different groups of rats, fear conditioning commenced either prior to puberty (P28 or P35) or after puberty (P56). Fear conditioning was measured using fear-potentiated startle. Both delay and trace fear conditioning were diminished by iron deficiency at P28 and P35. Hippocampal expression of the plasticity-related protein PKC-gamma was increased through trace fear conditioning, but reduced at P35 in the iron-deficient group. Trace fear conditioning was enhanced by prior iron deficiency in the P56 group. This unanticipated finding in iron-repleted adults is consistent with the effects of developmental iron deficiency on inhibitory avoidance learning, but contrasts with the persistent deleterious long-term effects of a more severe iron-deficiency protocol, suggesting that degree and duration of iron deficiency affects the possibility of recovery from its deleterious effects. (c) 2008 Elsevier B.V. All rights reserved.