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长时程冷暴露后大鼠下丘脑脑片视前区温敏神经元的适应性变化

孙久荣, 马永超, 赵文剑, 蔡益鹏

(北京大学生命科学学院生理及生物物理系，北京100871)

摘要

比较了生活在冷室((5士10C, 20只)和暖室((20士30C, 35只)达三周的雄性Wistar大
鼠下丘脑脑片视前区神经元电活动和温度敏感性，共记录到127个来自暖室组及86个来自冷室组自发放电神经元。结果表明:(1)冷适应后冷敏神经元的比例明显提高，温度敏感性不变而放电活动的临界温度和下限温度明显下移;(2)热敏神经元的温度敏感性和临界温度降低，但在37'C时的自发放电活动频率显著增加;(3)非温敏神经元的电活动也增加，其下限温度下移极显著，显示了大鼠视前区神经元在冷适应中的可塑性及其与冷适应中体温调节的机制相关。

关键词： 下丘脑脑薄片; 视前区温敏神经元; 冷适应; 神经元低温耐受性; 神经元可塑性

ADAPTIVE CHANGES OF PREOPTIC THERMOSENSITIVE NEURONS IN HYPOTHALAMIC TISSUE SLICES OF RATS AFTER LONG-TERM EXPOSURE TO COLD ENVIRONMENTAL TEMPERATURE

SUN JIU-RONG, MA YONG-CHAO, ZHAO WEN-JIAN , CAI YI-PENG

Department of Physiology, College of Life Sciences, Peking University, Beijing 100871)

Abstract

In the present work，thermosensitivity and spontaneous firing rate of 86 preoptic neurons in hypothalamic tissue slices from 20 cold acclimated rats (CR，at 5士1℃for more than 3 weeks) and 127 neurons from 35 warm acclimated rats (WR，at 20士3℃for the same period) were recorded and compared. The results showed that:(1)The percentage of cold-sensitive neurons in CR were higher than that in WR，the critical temperature and the lowest temperature of the spontaneous firing activity of cold-sensitive neurons in CR were also lower than that in WR. (2) Thermosensitivity and critical temperature of the warm-sensitive neurons in CR were remarkably decreased，and spontaneous firing rate under 37℃ was increased. (3) Spontaneous firing rate (37℃)of
temperature insensitive neurons in CR were conspicuously increased and the lowest ternperature extended downward. These profound changes in response to long-term cold exposure suggested that plasticity of preoptic neurons was involved in the thermoregulation in cold adaptation.

Key words: hypothalamic slice;preoptic thermosensitive neurons; cold acclimation;cold tolerance; neuronal plasticity

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引用本文：

孙久荣, 马永超, 赵文剑, 蔡益鹏. 长时程冷暴露后大鼠下丘脑脑片视前区温敏神经元的适应性变化[J]. 生理学报 1996; 48 (5): .

SUN JIU-RONG, MA YONG-CHAO, ZHAO WEN-JIAN , CAI YI-PENG. ADAPTIVE CHANGES OF PREOPTIC THERMOSENSITIVE NEURONS IN HYPOTHALAMIC TISSUE SLICES OF RATS AFTER LONG-TERM EXPOSURE TO COLD ENVIRONMENTAL TEMPERATURE . Acta Physiol Sin 1996; 48 (5): (in Chinese with English abstract).