Jauregui-Huerta Fernando, Ruvalcaba-Delgadillo Yaveth, Garcia-Estrada Joaquin, Feria-Velasco Alfredo, Ramos-Zuñiga Rodrigo, Gonzalez-Perez Oscar, Luquin Sonia
Departamento de Neurociencias, CUCS, Universidad de Guadalajara, Guadalajara, Mexico.
Neuro Endocrinol Lett. 2010;31(4):538-48.
This study investigated the cognitive effect of chronic exposure to environmental noise on RAWM performance of juvenile rats, and the ability of adult rats exposed to a novel acute stress to perform in the RAWM as a function of whether or not they were exposed to environmental noise as juveniles.
We examined the consequences of exposure to noise during the juvenile-early periadolescent period on adulthood stress response by assessing cognitive performance in the RAWM. Male rats were exposed to environmental noise during the childhood-prepubescent period (21-35 PND), and their RAWM performance was tested at the end of the exposure to noise, and then again two months later when they had to cope with a new stressful event. RAWM execution included a 3-day training phase and a reversal learning phase on day 4. Escape latency, reference memory errors and working memory errors were compared between experimental and control groups. In addition, body weight gain and serum corticosterone levels were evaluated.
Stressed rats demonstrated spatial impairment, as evidenced by poor execution on day 4. This effect was significantly noticeable in the doubly stressed group. Noise annoyance was evidenced by reduced body weight gain and increased serum corticosterone levels.
Our results suggest that environmental noise may produce potent stress-like effects in developing subjects that can persist into adulthood, affecting spatial learning abilities. This cognitive impairment may restrict the subject's ability to learn under a new spatial configuration.
本研究调查了长期暴露于环境噪声对幼年大鼠旷场试验行为表现的认知影响，以及成年大鼠在暴露于新的急性应激后进行旷场试验的能力，该能力取决于它们幼年时是否暴露于环境噪声。
我们通过评估旷场试验中的认知表现，研究了幼年至青春期早期暴露于噪声对成年期应激反应的影响。雄性大鼠在童年至青春期前阶段（出生后第21 - 35天）暴露于环境噪声，在噪声暴露结束时测试其旷场试验行为表现，然后在两个月后它们必须应对新的应激事件时再次测试。旷场试验包括为期3天的训练阶段和第4天的逆向学习阶段。比较实验组和对照组的逃避潜伏期、参考记忆错误和工作记忆错误。此外，评估体重增加和血清皮质酮水平。
应激大鼠表现出空间障碍，第4天的表现不佳证明了这一点。这种影响在双重应激组中尤为明显。体重增加减少和血清皮质酮水平升高证明了噪声烦扰。
我们的结果表明，环境噪声可能在发育中的个体中产生类似应激的强烈影响，这种影响可持续到成年期并影响空间学习能力。这种认知障碍可能会限制个体在新的空间配置下学习的能力。
