Clarke A S
Wisconsin Psychiatric Research Institute, Madison.
Dev Psychobiol. 1993 Dec;26(8):433-46. doi: 10.1002/dev.420260802.
Previous studies have found evidence of behavioral and psychophysiological differences between nonhuman primates reared in different social environments, however, few of these have employed longitudinal study of the animals over early development. In this study, HPA axis activity was assessed via measurement of ACTH and cortisol values over the first 6 months of life and in response to two stressful housing transitions in 48 infant rhesus monkeys that were either mother- or peer-reared. ACTH and cortisol values declined over the first 6 months in both rearing groups. Peer-reared monkeys showed lower levels of ACTH over the first 6 months of life than mother-reared, but the rearing groups did not differ in basal cortisol values over this period. Mother-reared animals showed a greater ACTH response to the mild stress of being moved to a new cage, and male monkeys showed higher values than females. Mother-reared animals showed the largest cortisol increase in response to the caging transition. Both groups showed increases in ACTH and cortisol in response to the more severe stress of separation from their rearing partners and housing with unfamiliar age-mates. Mother-reared animals again showed the largest increase in ACTH in response to these events, but increases in cortisol were similar among both sexes and rearing groups. These results suggest an interaction of sex and rearing history in response to stressful events.
以往的研究发现了在不同社会环境中饲养的非人类灵长类动物之间行为和心理生理差异的证据，然而，其中很少有研究对动物早期发育进行纵向研究。在本研究中，通过测量48只恒河猴幼崽在出生后前6个月的促肾上腺皮质激素（ACTH）和皮质醇值，并观察它们对两次应激性饲养环境转变的反应，来评估下丘脑-垂体-肾上腺（HPA）轴的活动。这些幼崽分别由母亲抚养或同伴抚养。在两个饲养组中，ACTH和皮质醇值在出生后的前6个月均有所下降。同伴抚养的猴子在出生后的前6个月中ACTH水平低于由母亲抚养的猴子，但在此期间，两组的基础皮质醇值没有差异。由母亲抚养的动物对转移到新笼子的轻度应激表现出更大的ACTH反应，并且雄性猴子的值高于雌性。由母亲抚养的动物对笼子转换的反应中皮质醇增加幅度最大。两组在与饲养伙伴分离并与陌生同龄动物一起饲养的更严重应激反应中，ACTH和皮质醇均升高。由母亲抚养的动物对这些事件的反应中ACTH再次表现出最大的增加，但皮质醇的增加在两性和饲养组中相似。这些结果表明，在应对应激事件时，性别和饲养经历之间存在相互作用。
