Department of Psychology and Neuroscience and Behavior Program, Barnard College of Columbia University, 3009 Broadway, New York, NY 10027, USA.
J Endocrinol. 2011 Sep;210(3):391-8. doi: 10.1530/JOE-11-0206. Epub 2011 Jul 11.
Prepubertal rats display heightened hormonal stress reactivity compared with adults in that levels of ACTH and corticosterone take twice as long (i.e. 40-60 min) to return to baseline following an acute stressor. Despite this substantial change in stress responsiveness, and the critical nature of the adolescence period of development, the maturation of the hormonal stress response from the time of pubertal onset to adulthood has not been thoroughly investigated. To examine this, we measured ACTH, corticosterone, and testosterone in 30-, 40-, 50-, 60-, and 70-day-old (i.e. spanning pubertal and adolescent development) male rats before and after a 30 min session of restraint stress. We found that the adult-like ACTH stress response develops between 50 and 60 days of age, while the corticosterone response changes between 30 and 40 days of age. We also found that adrenal corticosterone concentrations paralleled the plasma corticosterone response following restraint, suggesting that stress-induced adrenal corticosterone synthesis decreases during adolescent development and may, at least in part, contribute to the differential stress response observed before and after puberty. Finally, stress leads to increases in testosterone secretion, but only after 50 days of age. Collectively, these results indicate that shifts in hormonal stress responses occur throughout adolescent maturation and that these responses show distinct developmental profiles.
青春期前的大鼠与成年大鼠相比，表现出更高的激素应激反应性，因为 ACTH 和皮质酮水平需要两倍的时间（即 40-60 分钟）才能从急性应激源恢复到基线。尽管应激反应有如此大的变化，并且青春期是发育的关键时期，但从青春期开始到成年期的激素应激反应的成熟尚未得到彻底研究。为了研究这一点，我们在 30、40、50、60 和 70 天大（即跨越青春期和青少年发育）的雄性大鼠在 30 分钟束缚应激前后测量了 ACTH、皮质酮和睾酮。我们发现，类似成人的 ACTH 应激反应在 50-60 天之间发展，而皮质酮反应在 30-40 天之间变化。我们还发现，束缚后肾上腺皮质酮浓度与血浆皮质酮反应平行，这表明应激诱导的肾上腺皮质酮合成在青少年发育过程中减少，至少部分原因是青春期前后观察到的不同应激反应。最后，应激会导致睾酮分泌增加，但仅在 50 天后才会增加。总之，这些结果表明，激素应激反应在整个青少年成熟过程中发生变化，这些反应表现出不同的发育特征。
