布氏田鼠哺乳期低温经历抑制成年期神经再生

哺乳动物在出生前后所经历的环境条件对其成年后的行为和生理等具有重要影响。环境温度是影响动物后代表型的重要因素之一。本研究将分娩当天的布氏田鼠母体和幼仔在常温（23℃±1℃）或低温（4℃±1℃）饲养，断乳（21日龄）时转至常温环境，至第63日龄时再随机将两组动物各分为常温组和低温暴露组，期间检测体重、摄食量、静止代谢率、认知能力和神经细胞增殖和存活等，以验证哺乳期的低温经历可影响成年动物的代谢生理、行为表型和相关脑区神经再生的假说。结果发现：哺乳期低温经历导致成年布氏田鼠摄食量显著降低，与代谢有关的下丘脑以及学习记忆有关的海马区细胞增殖和存活数量减少。当动物在成年期面临冷暴露时，与哺乳期常温经历的动物相比，哺乳期低温经历的动物摄食量较低，在Y迷宫新异臂中的穿梭次数和停留时间显著降低，但海马和下丘脑部分核团的细 胞增殖以及海马CA的细胞存活明显升高。这表明哺乳期低温经历对布氏田鼠的能量代谢、行为和相关脑区的成体神经再生产生了持久的抑制效应，但成年后再次面对低温时，动物的代谢能力和代谢及学习记忆相关脑区的神经细胞可塑性优于哺乳期未曾经历低温的动物。

Cold experience during lactation inhibits adult neurogenesis in Brandt’s voles (Lasiopodomys brandtii)

Evidence has shown that environmental experiences during perinatal period play important roles in determining the behavior and metabolic physiology in adult mammals, especially the ambient temperature. The purpose of the present study was to test the hypothesis that the cold experience during lactation can have long-term effects on the metabolic physiology, behavioral performance and adult neurogenesis. The mother Brandt's voles (Lasiopodomys brandtii) together with their pups, on the day of parturition, were transferred to a warm room (23°C±1°C) or a cold room (4°C±1°C) until weaning (21 days), and then all animals were back to the warm room till 2 months old. Body mass, food intake, resting metabolic rate (RMR), cognitive ability, and neurogenesis in adulthood were measured. Our results showed that food intake, cell proliferation and cell survival of the brain decreased in the adult voles with cold experience during lactation compared to those with warm experience. When they were exposed to cold in adulthood, the voles with cold experience during lactation showed lower food intake, and lower frequency and duration of stay in the novel arm of Y-maze, but higher cell proliferation in the hippocampus and parts of hypothalamic areas, and higher cell survival in CA of hippocampus compared to those with warm experience during lactation. These data indicate that the cold experience during lactation has a long-lasting harmful effect on the energy metabolism, behavior and adult neurogenesis in Brandt's voles, but the voles with early cold experience will have better performance in metabolic capacity and neural plasticity in the brain regions related to metabolism and learning and memory when cold temperature comes again in later life.