GUSTATORY RESPONSES OF NEURONS IN THE PARABRACHIAL NUCLEUS OF RATS

Ａｎｕｍｂｅｒｏｆａｎａｔｏｍｉｃａｌ,ｅｌｅｃｔｒｏｐｈｙｓｉｏｌｏｇｉｃａｌａｎｄｂｅｈａｖｉｏｒａｌｅｘｐｅｒｉｍｅｎｔｓｈａｖｅｓｈｏｗｎｔｈａｔｇｕｓｔａｔｏｒｙｉｎｆｏｒｍａｔｉｏｎｉｎｔｈｅｎｕｃｌｅｕｓｏｆｔｈｅｓｏｌｉｔａｒｙｔｒａｃｔ(ＮＴＳ) ,ｗｈｉｃｈｉｓｃｏｎｖｅｙｅｄｆｒｏｍｔｏｎｇｕｅｖｉａｔｈｅｃｒａｎｉａｌｎｅｒｖｅｓ (ｆａｃｉａｌ,ｇｌｏｓｓｏｐｈａｒｙｎｇｅａｌ,ａｎｄｖａｇｕｓ) ,ｒｅａｃｈｅｓａｃｏｎｆｉｎｅｄ ｐａｒｔｏｆｔｈｅ ｐａｒａｂｒａｃｈｉａｌｎｕｃ…

GUSTATORY RESPONSES OF NEURONS IN THE PARABRACHIAL NUCLEUS OF RATS

Objective To investigate the gustatory neural response of the neurons to five basic taste stimuli in the parabrachial nucleus (PBN). Methods Evoked responses from PBN taste neurons to tastants were recorded using standard extracellular microelectrode technique. Results 46 taste neurons were recorded in PBN, and most of them were broadly responsive. On the basis of their most effective taste stimuli, these taste neurons were classified into five types. Those are NaCl-, HCl-, quinine-, sucrose-, and monosodium glutamate (MSG)-best neurons. Except for the quinine-best neurons, the responses of each best-stimulus category to its best stimulus were significantly stronger than those of others (P<0.01). The results of correlation analysis showed that the correlations between sucrose and each of the other 4 tastants were smaller than those among others. Conclusion The results suggest that PBN taste neurons probably play an important role in discriminating for hedonic taste.