Division of Neurology, Dept. of Pediatrics, Cincinnati Children's Research Foundation and University of Cincinnati College of Medicine, Cincinnati, OH 45229-3039, USA.
Neurotoxicol Teratol. 2012 Jan-Feb;34(1):136-42. doi: 10.1016/j.ntt.2011.08.004. Epub 2011 Aug 11.
In rats, neonatal (+)-methamphetamine (MA) exposure and maternal separation stress increase corticosterone during treatment and result in learning and memory impairments later in life. Early-life stress also changes later responses to acute stress. We tested the hypothesis that neonatal MA exposure would alter adult corticosterone after acute stress or MA challenge. Rats were treated with MA (10 mg/kg × 4/day), saline, or handling on postnatal (P) days 11-15 or 11-20 (days that lead to learning and memory impairments at this dose). As adults, corticosterone was measured before and after 15 min forced swim (FS) or 15 min forced confinement (FC), counterbalanced, and after an acute MA challenge (10 mg/kg) given last. FS increased corticosterone more than FC; order and stress type interacted but did not interact with treatment; treatment interacted with FS but not with FC. In the P11-15 regimen, MA-treated rats showed more rapid increases in corticosterone after FS than controls. In the P11-20 regimen, MA-treated rats showed a trend toward more rapid decrease in corticosterone after FS. No differences were found after MA challenge. The data do not support the hypothesis that neonatal MA causes changes in adult stress responsiveness to FS, FC, or an acute MA challenge.
在大鼠中，新生（+）-甲基苯丙胺（MA）暴露和母体分离应激会在治疗期间增加皮质酮，并且导致生命后期的学习和记忆障碍。早期生活压力也会改变对急性应激的后期反应。我们检验了这样一个假设，即新生 MA 暴露会改变急性应激或 MA 挑战后的成年皮质酮。大鼠在出生后第 11-15 天或第 11-20 天（以这种剂量导致学习和记忆障碍）接受 MA（10mg/kg×4 天）、盐水或处理。作为成年人，在 15 分钟强制游泳（FS）或 15 分钟强制限制（FC）之前和之后测量皮质酮，平衡，最后给予急性 MA 挑战（10mg/kg）。FS 比 FC 更能增加皮质酮；顺序和应激类型相互作用，但与处理无关；处理与 FS 相互作用，但与 FC 无关。在 P11-15 方案中，与对照组相比，MA 处理的大鼠在 FS 后皮质酮的增加更为迅速。在 P11-20 方案中，MA 处理的大鼠在 FS 后皮质酮的减少趋势更为明显。在 MA 挑战后没有发现差异。数据不支持新生 MA 导致 FS、FC 或急性 MA 挑战对成年应激反应性变化的假设。
