D'Amato F R, Cabib S
Istituto di Psicobiologia e Psicofarmacologia, C.N.R., Rome, Italy.
Behav Neural Biol. 1987 Sep;48(2):197-205. doi: 10.1016/s0163-1047(87)90738-2.
This study was designed to assess the stress effect of manipulation of the olfactory environment in developing mice. In a first experiment it was found that mouse pups could be stressed (as measured by an increase in ultrasonic calls) by removing the litter from the dam for 15 min/day for the first 14 days of life and exposing them to a novel odor (clean bedding). This stress procedure also produced a long-term modification in maternal behavior. The stress response (ultrasounds) and the modification of maternal behavior were prevented by providing the litter with home cage bedding during maternal separation. In a second experiment it was demonstrated that early stress influenced apomorphine-induced wall climbing behavior in 15-day-old mice, suggesting stress-induced alterations in the dopaminergic system. Pups exposed to clean bedding during infancy exhibited more wall climbing behavior than pups never separated from the mother. Moreover, preventing the early stress response during mother-offspring separation, by providing pups with home cage bedding, eliminated the increase in apomorphine-induced wall climbing. Taken together these results suggest that olfactory cues are decisive in characterizing stressful situations inducing both immediate and long-lasting effects in mouse pups.
本研究旨在评估操控发育中小鼠的嗅觉环境所产生的应激效应。在第一个实验中，研究人员发现，在小鼠出生后的头14天里，每天将幼崽与母鼠分开15分钟，并使其暴露于一种新气味（干净垫料）中，幼崽会产生应激反应（通过超声波鸣叫增加来衡量）。这种应激程序还会对母性行为产生长期改变。在母鼠与幼崽分离期间，给幼崽提供来自原饲养笼的垫料，可防止应激反应（超声波）和母性行为的改变。在第二个实验中，研究人员证明，早期应激会影响15日龄小鼠对阿扑吗啡诱导的攀壁行为，这表明应激会导致多巴胺能系统发生改变。在幼年期接触干净垫料的幼崽比从未与母亲分离的幼崽表现出更多的攀壁行为。此外，在母鼠与幼崽分离期间，给幼崽提供来自原饲养笼的垫料以防止早期应激反应，可消除阿扑吗啡诱导的攀壁行为的增加。综合这些结果表明，嗅觉线索对于确定在小鼠幼崽中诱发即时和长期效应的应激情况起着决定性作用。
