Otto-von-Guericke-Universität, Institut für Biochemie und Zellbiologie, Magdeburg, Germany.
PLoS One. 2013;8(1):e54427. doi: 10.1371/journal.pone.0054427. Epub 2013 Jan 16.
When tested for their behavioural performance, the mixed genetic background of transgenic mice is a critical, but often ignored, issue. Such issues can arise because of the significant differences in defined behavioural parameters between embryonic stem cell donor and recipient strains. In this context, the commonly used stem cell donor strain '129' shows 'deficits' in different paradigms for learning and long-term memory. We investigated the long-term social recognition memory performance and the investigative behaviour in commercially available 129S1/SvImJ and C57BL/6JOlaHsd mice and two F1-hybrids (129S1/SvImJ×C57BL/6JOlaHsd) by using the social discrimination procedure and its modification, the volatile fraction cage (VFC). Our data revealed an unimpaired olfactory long-term recognition memory not only in female and male 129S1/SvImJ and C57BL/6JOlaHsd mice but also in the two hybrid lines (129S1/SvImJxC57BL/6JOlaHsd) when the full 'olfactory signature' of the 'to-be-recognized' conspecific was presented. Under these conditions we also failed to detect differences in the long-term recognition memory between male and female mice of the tested strains and revealed that the oestrus cycle did not affect the performance in this memory task. The performance in the VFC, based only on the volatile components of the 'olfactory signature' of the 'to-be-recognized' conspecific, was similar to that observed under direct exposure except that females of one F1 hybrid group failed to show an intact long-term memory. Thus, the social discrimination procedure allowing direct access between the experimental subject and the stimulus animal(s) is highly suitable to investigate the impact of genetic manipulations on long-term memory in male and female mice of the strain 129S1/SvImJ, C57BL/6JOlaHsd and 129S1/SvImJxC57BL/6JOlaHsd hybrids.
当对其行为表现进行测试时，转基因小鼠的混合遗传背景是一个关键但经常被忽视的问题。这种问题可能是由于胚胎干细胞供体和受体品系之间定义的行为参数存在显著差异而引起的。在这种情况下，常用的干细胞供体品系“129”在不同的学习和长期记忆范式中表现出“缺陷”。我们通过使用社会辨别程序及其变体挥发性成分笼（VFC），研究了商业可得的 129S1/SvImJ 和 C57BL/6JOlaHsd 小鼠以及两种 F1 杂种（129S1/SvImJ×C57BL/6JOlaHsd）的长期社交识别记忆表现和探究行为。我们的数据显示，不仅在雌性和雄性 129S1/SvImJ 和 C57BL/6JOlaHsd 小鼠中，而且在两种杂交品系（129S1/SvImJ×C57BL/6JOlaHsd）中，当呈现“要识别”同种动物的完整“嗅觉特征”时，嗅觉的长期识别记忆没有受损。在这些条件下，我们也未能检测到测试品系中雄性和雌性小鼠之间的长期识别记忆差异，并揭示了发情周期不会影响该记忆任务的表现。基于“要识别”同种动物的“嗅觉特征”的挥发性成分的 VFC 性能与直接暴露时观察到的性能相似，只是一个 F1 杂种组的雌性动物未能表现出完整的长期记忆。因此，允许实验对象与刺激动物之间直接接触的社交辨别程序非常适合研究遗传操作对 129S1/SvImJ、C57BL/6JOlaHsd 和 129S1/SvImJxC57BL/6JOlaHsd 杂种小鼠的雄性和雌性长期记忆的影响。
