大鼠脑桥臂旁核味觉神经元的生理学特性

The physiological characteristics of taste neurons in the parabrachial nuclei of rats

采用微电极细胞外记录技术 ,观察和分析了大鼠脑桥臂旁核 (Parabrachialnuclei,PbN)味觉神经元的反应特征。记录到的 5 5个PbN味觉神经元中 ,绝大部分位于脑桥味区并有自发放电。大部分PbN味觉神经元对多种基本味觉刺激起反应 ,其中对氯化钠反应的频率最高。PbN味觉神经元对蔗糖的反应和对其他味觉反应的相关性都较低。根椐最适刺激 ,PbN味觉神经元可分为 :氯化钠优势反应、盐酸优势反应、奎宁优势反应和蔗糖优势反应神经元。结果提示 ,PbN中存在不同类型的神经元 ,它们可能在味觉的传递和编码中发挥着重要作用。

The present study was undertaken to investigate the electrophysiological properties of the parabrachial nuclei (PbN) taste neurons by using the extracellular recording technique. Among 55 taste neurons recorded, most located in pontine taste area (PTA) and were spontaneously active. The majority of the taste neurons responded to at least two of the five basic taste qualities (salt, sour, bitter, sweet and umami). The evoked response to NaCl was highest among the five tastants. The analysis of across unit patterns indicated that response to sucrose had a lower correlation with those to other stimuli. According to their preferred stimuli, PbN taste neurons could be classified as NaCl , HCl , quinine and sucrose preferred taste neurons, which were differentially distributed in parabrachial subnuclei. The results indicate that there are different groups of taste neurons in PbN in terms of their responses to tastants and they may play important roles in gustatory transmission and coding. \[