• 한국식품과학회지
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• 제23권1호
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• pp.37-43
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• 1991

고양이의 고색신경(chorda tympani nerve)을 통한 미각신형 impulse 발사시험을 실시하여 MSG의 미각신경 반응특징을 기본맛의 그것과 비교하였으며 MSG 용액의 첨가가 기본맛 성분의 미각반응 impulse 강도에 미치는 영향을 조사하였다. 고양이의 혀에 자극된 맛성분의 종류와 농도에 따라 고색신경을 통한 신경 impulse 발사빈도수는 다르게 나타났다. 구연산에 대한 반응 impulse가 가장 높은 빈도수를 나타내었고 NaCl, KCl, MSG가 비슷한 수준이었고 sucrose는 다른 맛성분에 비하여 그 반응정도가 낮게 나타났다. 여러 가지 다른 농도의 MSG 용액으로 미리 자극된 맛성분을 투하할 경우 식염의 짠맛에 대한 반응은 MSG 농도 0.02 M에서 크게 증가되나 0.08 M에서 증가폭이 다소 낮아졌다. 설탕의 경우, MSG에 의하여 반응 impulse가 약화되는 경향을 나타내었으며 구연산의 경우에는 MSG에 의하여 반응 impulse 빈도수가 뚜렸이 감소하였다.

• The Korean Journal of Physiology
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• 제21권2호
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• pp.313-321
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• 1987

To investigate whether the cervical sympathetics contains specific secretory fibers for the salivary glands, reflex salivation was evoked and the role of the sympathetics or the reflex was examined in ketamine-anesthetized cat. Stimulation of the central end of the glossopharyngeal nerve produced a copious secretion from the submaxillary gland and the response was not affected by the section of the cervical sympathetics or by the administration of phenoxybenzamine, whereas the response was abolished by severing the chorda tympani or by the administration of atropine. The salivary response was always associated with an increase in glandular blood flow. Both salivary and blood flow responses were decreased markedly by the superimposed stimulation of the cervical sympathetics or by the administration of norepinephrine. The decreased submaxillary blood flow always preceded the decrease in salivary flow on stimulation of the cervical sympathetics and the decreased blood flow recovered prior to the salivary flow upon cessation of the sympathetic stimulation. The inhibitory effects of the sympathetics and norepinephrine were completely abolished by the pretreatment with phenoxybenzamine. These results indicate that the glossopharyngeal nerve is one of the afferent limbs of the submaxillary salivary reflex and the chorda tympani is the only efferent limb of the reflex pathway. Thus, it is suggested that the cervical sympathetics does not contain the specific secretory fibers for the gland, but plays a role in inhibiting the reflex secretion by decreasing the blood flow to the gland.

• The Korean Journal of Physiology
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• 제25권1호
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• pp.87-99
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• 1991

In order to elucidate whether capsaicin applied topically acts as a pain-producing subastance or as a tastant, neuronal activities of the chorda tympani nerve(CN), lingual nerve(LN), solitary tract nucleus(STN), and trigeminal nucleus(TGN) were recorded while thermal and taste stimuli, and capsaicin were being applied topically, and algesics intra-arterially to the tongue of cats anesthetized with ${\alpha}-chloralsoe$. In addition, the STN neurons were examined after wheat germ agglutinin-horseradish peroxidase(WGA-HRP) was applied to the CN. The CN fibers responded to taste and thermal stimuli, algesics, and capsaicin. Responses to capsaicin were significantly correlated with those to taste and thermal stimuli. The LN fibers mainly responded to mechanical and thermal stimuli, algesics, and capsaicin. Responses to capsaicin were significantly correlated with those to algesics. The STN neurons responded to taste and thermal stiumli, algesics, and capsaicin. Responses to capsaicin were significantly correlated with those to taste and thermal stiumli in somewhat different fashion from those of the CN fibers. The TGN neurons mainly responded to mechanical stimuli, algesics, and capsaicin. Correlations between responses to capsaicin and any others were not significant. After WGA-HRP was applied to the CN, the STN neurons which receive input from the CN were identified largely in the medio-ventral portion to the solitary tract. These results suggest that capsaicin produce taste as well as pain sensation. Sensory information evoked by capsaicin can be conveyed to the STN, especially medio-ventral portion, via the CN as gustatory information on the one hand, and to the STN or TGN via the LN as noxious information on the other. In addiation, the noxious information may be conveyed to the STN via the CN.