Stress sensitization during the juvenile period in rodents: Impact of neurotrophins and behavioral flexibility

应激源可能会导致神经生物学过程(如神经递质、激素和生长因子)的“敏感化”，从而使后来对应激源的反应被明显夸大。此外，还可能发生“交叉敏化”效应，即应激源增强对不同挑战(例如，可卡因或免疫作用剂)的后期反应。啮齿动物的致敏效应可发生在任何年龄，但如果应激源最初出现在生命早期(出生后最初几天)或青春期(少年)，则尤其明显。这些敏化效应被不同地归因于大脑中特定受体的敏感性改变，或生长因子功能的改变，其中一些可能源于表观遗传变化。

Stressors may engender the ‘sensitization’ of neurobiological processes (e.g., neurotransmitter, hormone and growth factors) so that later responses to stressors are markedly exaggerated. As well, ‘cross-sensitization’ effects may occur wherein a stressor augments the later response to a different challenge (e.g., cocaine or immune acting agents). Sensitization effects in rodents can occur at any age, but are especially pronounced if the stressor was initially encountered in early life (first few postnatal days) or during the adolescent (juvenile) period. These sensitization effects have variously been attributed to altered sensitivity of particular receptors in brain, or altered growth factor functioning, some of which may stem from epigenetic changes.