Lai Jonathan K Y, Sobala-Drozdowski Monica, Zhou Linghong, Doering Laurie C, Faure Paul A, Foster Jane A
Department of Psychiatry and Behavioural Neuroscience, McMaster University, Canada.
Department of Psychology, Neuroscience & Behaviour, McMaster University, Canada.
Behav Brain Res. 2014 Feb 1;259:119-30. doi: 10.1016/j.bbr.2013.10.049. Epub 2013 Nov 7.
The fmr1 knock out (KO) mouse has been a useful animal model to understand pathology and treatment of FXS, both anatomically and behaviorally. Ultrasonic vocalizations (USVs) are a behavioral tool to assess early life communication deficits in mice. Here, we report on the temporal and spectral features of USVs emitted after maternal separation in wild type (FVB/N) and fmr1 KO pups at postnatal days (P) P4, P7 and P10. The results show changes in the number and duration of calls in fmr1 KO pups and wild type pups were dependent on age and call type. Fmr1 KO pups showed an increased number of USVs at P7 but not at P4 or P10. This increase was specific to Frequency Jump calls. In addition, fmr1 KO mice showed a developmental shift in the temporal distribution of calls, with P10 mice calling in distinct bout patterns. Overall, these findings provide evidence that changes in USV outcomes were specific to certain call types and ages in fmr1 KO mice. Because early postnatal life is a window during which multiple neural systems activate and become established, behavioral measures such as using USVs as a measure of communication, may be useful as a predictor of brain changes and later developmental behavioral changes. Work is needed to better understand the functional outcomes of altered development of USVs and how these changes contribute to later emergence of autistic-like behaviors in animal models of autism.
Fmr1基因敲除（KO）小鼠已成为一种有用的动物模型，可从解剖学和行为学角度了解脆性X综合征（FXS）的病理学及治疗方法。超声发声（USVs）是评估小鼠早期生活中交流缺陷的一种行为工具。在此，我们报告了野生型（FVB/N）和fmr1基因敲除幼崽在出生后第4天（P4）、第7天（P7）和第10天（P10）母婴分离后发出的超声发声的时间和频谱特征。结果表明，fmr1基因敲除幼崽和野生型幼崽叫声的数量和持续时间变化取决于年龄和叫声类型。fmr1基因敲除幼崽在P7时超声发声数量增加，但在P4或P10时没有增加。这种增加特定于频率跳跃叫声。此外，fmr1基因敲除小鼠在叫声的时间分布上表现出发育变化，P10的小鼠以不同的发声模式发声。总体而言，这些发现提供了证据，表明超声发声结果的变化在fmr1基因敲除小鼠中特定于某些叫声类型和年龄。由于出生后早期是多个神经系统激活并建立的时期，像使用超声发声作为交流测量手段这样的行为测量方法，可能有助于预测大脑变化和后期发育行为变化。需要开展工作以更好地理解超声发声发育改变的功能结果，以及这些变化如何导致自闭症动物模型中类似自闭症行为的后期出现。
