Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Juriquilla, Querétaro, Mexico.
Nutr Neurosci. 2011 Jul;14(4):145-50. doi: 10.1179/147683011X13009738172567.
Malnutrition produces changes in the central nervous system (CNS) of mammals during development, related to the intensity and timing of the malnutrition insult during the pre- or postnatal period. Protein malnutrition produces irreversible changes in hippocampal formation and some brain stem nuclei. The suprachiasmatic nucleus (SCN) is dramatically altered by low-protein diets during the gestational and perinatal periods. Also, it is known that circadian oscillators regulate physiological, behavioral, and cognitive processes and there is evidence that the time-place learning process exhibits a daily temporal distribution. The aim of this study was to determine the effects of chronic, prenatal, or postnatal malnutrition on daily patterns of the time-place learning process in the adult rat. Forty Sprague-Dawley male 90-day-old rats, were divided into four groups: 10 well nourished controls (Co), 10 chronically (CM), 10 prenatally malnourished (PrM), and 10 postnatally malnourished (PtM) rats. Efficiency in time-place learning was tested by using a behavioral T-maze. Each rat was assayed for 10 trials before considering the final probe of efficiency. Each trial was 60 seconds long, final efficiency was measured by the amount of time the rat took to reach the end of an arm containing a water pot. Each rat was tested in 2-hour spans until completion of a full 24-hour cycle. A Cosinor analysis was used to evaluate acrophase and percentage of rhythmicity. The obtained results suggest that time-place learning process is influenced by the circadian clock. The severity and timing of prenatal or chronic protein malnutrition modifies the acrophase and rhythmicity of the learning circadian pattern, which can impact important cognitive functions.
营养不良会导致哺乳动物在发育过程中中枢神经系统（CNS）发生变化，这与出生前或出生后营养不良的强度和时间有关。蛋白质营养不良会对海马结构和一些脑干核产生不可逆转的影响。低蛋白饮食在妊娠期和围产期会对视交叉上核（SCN）产生巨大影响。此外，众所周知，昼夜节律振荡器调节生理、行为和认知过程，有证据表明，时间-地点学习过程表现出每日时间分布。本研究旨在确定慢性、产前或产后营养不良对成年大鼠时间-地点学习过程的日常模式的影响。将 40 只雄性 Sprague-Dawley 大鼠分为 4 组：10 只营养良好的对照组（Co）、10 只慢性（CM）、10 只产前营养不良组（PrM）和 10 只产后营养不良组（PtM）。通过使用行为 T 迷宫测试来评估时间-地点学习效率。在考虑最终效率探针之前，对每组大鼠进行 10 次测试。每次试验持续 60 秒，最终效率通过大鼠到达含有水罐的臂末端所需的时间来衡量。每组大鼠在 2 小时的时间跨度内进行测试，直到完成完整的 24 小时周期。使用 Cosinor 分析评估峰相和节律性百分比。结果表明，时间-地点学习过程受昼夜节律的影响。产前或慢性蛋白质营养不良的严重程度和时间会改变学习昼夜节律模式的峰相和节律性，这可能会影响重要的认知功能。
