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目的 研究臂旁外侧核(LPB)自发放电神经元的温敏特性.方法 采用红外可视脑片膜片钳胞外记录技术,观察温度对LPB神经元自发放电频率和幅度的影响,分析LPB热敏、冷敏神经元的分布、形态学和电生理学特点.结果 温度变化对LPB不同类型神经元放电频率的影响不同,热敏神经元放电频率随温度升高明显加快;冷敏神经元放电频率随温度升高明显减慢.在参与前馈调节的3个亚核即LPBel、LPBc和LPBd,热敏和冷敏神经元均有分布,但其分布百分比差异无统计学意义(P＞0.05).LPB热敏神经元的温敏系数范围为0.8～3.4imp/(s·℃),冷敏神经元的温敏系数范围为-0.6～-4.2imp/(s·℃);在32℃、36℃和39℃3个温度条件下,热敏神经元放电频率均快于温度不敏感神经元(P ＜0.05);LPB神经元胞体形态呈椭圆形、梭形、三角形或圆形,虽然LPB 3类神经元胞体形态有所不同,但4种形态神经元的比例差异无统计学意义(P＞0.05);温度变化对三类神经元的放电幅度均无明显影响(P＞0.05).结论 LPB部分神经元的自发放电活动具有温度敏感度,存在内在温度感受机制.“,”Objective To investigate the temperature-sensitive properties of rat lateral parabrachial (LPB) neurons.Methods The spontaneous firing rate and amplitude of LPB neurons in rat brainstem slices during changes in temperature was extracellularly monitored by loose-seal cell-attached patch clamp recordings,and the location,morphological,and electrophysiological properties of temperature-sensitive neurons in LPB were analysed.Results LPB neurons were classified into three types including warm-sensitive,cold-sensitive and temperature-insensitive neurons according to the temperature coefficients of their firing rate in response to temperature changes.In warm-sensitive neurons,warming increased their firing rate.On the contrary,warming decreased the firing rate of cold-sensitive neurons.The temperature-sensitive neurons were located in LPBel,LPBc and LPBd,the three LPB subnuclei responsible for the transmission of cutaneous feedforward signals,and the percentages of warm-and cold-neurons within the three LPB subnuclei were not significantly different(P ＞ 0.05).The spontaneous firing rate of the warm-sensitive neurons was all significantly greater than that of the temperature-insensitive neurons at 32℃,36℃ and 39℃ (P ＜ 0.05).Temperature coefficients,for the warm-sensitive neurons in the LPB,ranged from 0.8 to 3.4imp/(s · ℃);for the cold-sensitive neurons,ranged from-0.6 to-4.2imp/(s · ℃).Although the three types of LPB neurons appeared to have different cell morphology,there was,in fact,no significant difference in the proportions of the fusiform,oval,triangular,and round neurons(P ＞ 0.05).In addition,temperature had no effects on the firing amplitude of rat LPB neurons(P ＞ 0.05).Conclusion Some neurons are inherently temperature sensitive in their spontaneous firing activity in the LPB.