Functional collumn of taste neurons in gustatory cortex in rats.

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 15500285
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Neurophysiology and muscle physiology
• Research Institution: Kumamoto University
• Principal Investigator: OGAWA Hisashi Kumamoto University, Faculty of Medical and Pharmaceutical Sciences Sensory and Cognitive Physiology, Professor, 大学院・医学薬学研究部, 教授 (20040181)
• Co-Investigator(Kenkyū-buntansha): HAYAMA Tomio Kumamoto University, Faculty of Medical and Pharmaceutical Sciences, Sensory and Cognitive Physiology, Associate Professor, 大学院・医学薬学研究部, 助教授 (50128302) ; HASESGAWA Kayoko Kumamoto University, Faculty of Medical and Pharmaceutical Sciences, Sensory and Cognitive Physiology, Instructor, 大学院・医学薬学研究部, 助手 (80136720)
• Project Period (FY): 2003 – 2004
• Keywords: rat / gustatory cortex / functional column / taste nurons

Research Abstract

In the preceding paper, we described that mechanoreceptive neurons are arranged in a functional column in the primary gustatory cortex(GC) in rats(Wang and Ogawa,2002), and that the size of the columnar diameter varied depending on the receptive features. We also noted the evidence that gustatory neurons may similarly be arranged there, depending on the best stimulus among the four basic tastes. In the present study, we recorded neuronal activities every 50-100 μm by inserting microelectrodes to the cerebral cortex with various angles the cortical surface. We also characterized receptive features(best stimulus and receptive field) of taste and mechanoreceptive neurons recorded. Taste neurons were recorded at 49 of the 68 tracks histologically reconstructed. On average, 6.3(ranging 1-16) taste neurons were encountered every successful track. However, one or two taste neurons were successively encountered in most tracks, but 5-6 taste neurons happened to be encountered succesively in a few track. When two or more taste neurons sharing the best stimulus and receptive field properties in common were successively recorded, the columnar size was measured by projecting the width of the recording places on the cortical surfaces and was estimated about 30 μm. This size was compatible with the value estimated by cross-correlation analysis(Nakamura and Ogawa,1997). Parts of the results were presented to the International Symposium on Olfaction and Taste, held in Kyoto, Japan, in July,2004.