Institute of Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova str., 5A, Moscow, 117485, Russia.
Institute of Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova str., 5A, Moscow, 117485, Russia.
Behav Brain Res. 2019 Nov 18;374:112143. doi: 10.1016/j.bbr.2019.112143. Epub 2019 Aug 6.
Developmental milestones are behavioral and physical skills which are considered as markers of neurodevelopment. In rodents, sensory input from whiskers plays a crucial role in development of brain functions. Development of whisker system in rats includes the early period of passive whisker touch (PN1-8) before the onset of coordinated whisker movements which underlie active sensing. Inasmuch as transitioning from passive to active sensing requires a strong sensorimotor integration, we assume that the effect of whisker deprivation during the period of passive touch is unfavorable for neurodevelopment, but deprivation after the onset of active sensing might elicit less harmful effect due to compensatory neuroplalstic changes. Here we examined the effect of complete whisker trimming (WT) in WAG/Rij rats during PN1-8 and PN9-16 (active sensing) on achieving developmental milestones (e.g., eyelid opening, walking, self-grooming, rearing activity, physical maturation of forelimbs), locomotor activity and body weight. Control groups underwent sham trimming during the same periods. WT during PN1-8 caused a delay in achieving all investigated milestones, but WT during PN9-16 delayed only self-grooming. Both WT/sham trimming during PN9-16 caused a delay in explorative behavior, but accelerated self-grooming. These changes are likely to link with the effect of manipulations during PN9-16 in previously unhandled pups, but not specifically with WT. In general, developmental milestones appeared to be an informative tool to access neurodevelopment in rat pups and might have a translational value for studying developmental disorders during early life.
发展里程碑是行为和身体技能，被认为是神经发育的标志物。在啮齿动物中，来自胡须的感觉输入在大脑功能的发育中起着至关重要的作用。大鼠胡须系统的发育包括协调的胡须运动之前的被动胡须触摸早期阶段（PN1-8），这是主动感知的基础。由于从被动到主动感知的转变需要强烈的感觉运动整合，我们假设在被动触摸期间剥夺胡须会对神经发育不利，但在主动感知开始后剥夺可能会由于代偿性神经可塑性变化而产生较小的有害影响。在这里，我们研究了在 PN1-8 和 PN9-16（主动感知）期间对 WAG/Rij 大鼠进行完全胡须修剪（WT）对达到发展里程碑（例如，眼睑张开、行走、自我梳理、后肢活动、前肢身体成熟）、运动活动和体重的影响。对照组在同一时期接受了假修剪。PN1-8 期间的 WT 导致所有研究里程碑的延迟，但 PN9-16 期间的 WT 仅延迟自我梳理。PN9-16 期间的 WT/假修剪均导致探索行为延迟，但加速了自我梳理。这些变化可能与在以前未处理的幼崽中在 PN9-16 期间进行的操作的影响有关，但与 WT 无关。总的来说，发展里程碑似乎是评估大鼠幼崽神经发育的一种信息工具，并且可能对研究生命早期发育障碍具有转化价值。
