Changes of gustatory preference with age in the rat
ロウカ ニ ト モナウ ラット ノ ミカク シコウセイ ノ ヘンカ
原田, 秀逸 ,
19 , 鹿児島大学
"The effect of aging on taste were compared between the preference and neural responses from the greater superficial petrosal nerve (GSP) innervating the soft palate and the chorda tympani nerve (CT) innervating the fungiform papillae in the young (5-12 weeks) and aged (19-22 months) Sprague Dawley rat. A two-bottle preference test revealed that younger rats significantly preferred 0.001 M 5'-inosine monophosphate (IMP), 0.01 M mono sodium glutamate (MSG), and binary mixtures of 0.001 M IMP + 0.01 M MSG than deionized water. However, aged rats showed no significant preference to these umami solutions. Among the other four basic taste stimuli, there was no significant difference in preference between young and aged rats. Regardless of the age of the rat, neural responses from the GSP and CT produced robust integrated responses to all three umami solutions the same as used in the two-bottle test. These results indicate that the lack of preference to umami in aged rats is occurred in the central nervous system, suggesting that the loss of preference to umami taste in aged rats may be caused by homeostatic changes in the brain."