INDIVIDUAL DIFFERENCES IN MATERNAL CARE IN THE RAT

描述（改编自申请人的摘要）： 母亲行为的变化调节了行为和 大鼠对应激的内分泌反应（参见Lie等人，《科学》，199;卡尔吉 等，1998 PNAS in Appendix）。也许关键的发现是， 婴儿期护理调节中央CRF系统的发展， 激活对压力的行为、内分泌和自主反应。的变化 母亲的照顾也会影响幼鼠神经系统的发育。 系统，如糖皮质激素和GABA α受体系统，其提供了一种免疫调节剂。 对CRF合成和释放的抑制作用。因此，母亲的后代 表现出低水平的母亲舔/梳理和拱背护理 (Low LG-ABN）显示CRF表达增加，糖皮质激素和 与高LG-ABN母亲的后代相比，GABA a受体水平。 成年子代PVNh中CRF mRNA表达水平为 与母亲舔/梳理的水平和 在出生后的头10天进行驼背哺乳。我们的初步数据 这表明，这些影响提供了一个例子的行为传播 从一代到下一代的特征。下一个问题是关于 母亲行为的个体差异。 这里的主要目标是了解神经生物学基础， 环境刺激、个体差异 在父母的行为和发展的行为和内分泌反应 压力推动这一赠款的假设试图解释这些 环境对神经系统发育的影响 以及那些调解父母照顾的恐惧。实验 这里提出的是旨在解决这三个主要原则 假设：1）母亲行为的个体差异是遗传的 通过行为传播模式，2）产妇护理的变化是 与神经系统的个体差异有关， 压力反应和母性行为的表达，3）有一个 应激反应个体差异之间的函数关系 和那些在产妇护理，和4），这种个体差异，在 反过来，在功能上与所面临的环境需求水平有关 动物（更紧张的环境导致低LG-ABN母亲， 对压力更敏感的后代）。

DESCRIPTION (Adapted From The Applicant's Abstract): Variations in maternal behavior regulate the development of behavioral and endocrine responses to stress in the rat (see Lie et al., Science, 199; Caldji et al., 1998 PNAS in Appendix). Perhaps the pivotal finding is that maternal care in infancy regulates the development of central CRF systems which serve to activate behavioral, endocrine and autonomic responses to stress. Variations in maternal care in the infant rat also influences the development of neural systems, such as glucocorticoid and GABAa receptor systems, which provide an inhibitory tone over CRF synthesis and release. Thus, the offspring of mothers which exhibit a low level of maternal licking/grooming and arched-back nursing (Low LG-ABN) show increased CRF expression, and decreased glucocorticoid and GABAa receptor levels by comparison to the offspring of High LG-ABN mothers. The level of CRF mRNA expression in the PVNh of the adult offspring was significantly correlated with the level of both maternal licking/grooming and arched-back nursing during the first 10 days of life. Our preliminary data suggest that these effects provide an example of the behavioral transmission of traits from one generation to the next. The next question concerns the origins of these individual differences in maternal behavior. The primary goal here is to understand the neurobiological basis for the relationships that exist between environmental stimuli, individual differences in parental behavior and the development of behavioral and endocrine responses to stress. The hypothesis which drives this grant attempts to explain these environmental effects in terms of the development of neural systems underlying fearfulness as well as those which mediate parental care. The experiments proposed here are designed to address the three principal tenets of this hypothesis: 1) that individual differences in maternal behavior are inherited via a behavioral mode of transmission, 2) that variations in maternal care are associated with individual differences in neural systems that mediate the expression of both stress reactivity and maternal behavior, 3) that there is a functional relationship between the individual differences in stress reactivity and those in maternal care, and 4) that such individual differences are, in turn, functionally related to the level of environmental demand which confronts the animal (more stressful environments result in Low LG-ABN mothers and offspring that are more reactive to stress).