• The Korean Journal of Pain
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• 제9권1호
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• pp.26-38
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• 1996

In a normal state, sympathetic efferent activity does not elicit discharges of sensory neurons, whereas it becomes associated with and excites sensory neurons in a pathophysiological state such as injury to a peripheral nerve. Although this sympathetic-sensory interaction is reportedly adrenergic, involved subtypes of adrenoreceptors are not yet clearly revealed. The purpose of this study was to determine which adrenorceptor subtypes were involved in sympathetic-sensory interaction that was developed in rats with an experimental peripheral neuropathy. Using rats that received a tight ligation of one or two of L4-L6 spinal nerves 10~15 days previously, a recording was made from afferent fibers in microfilaments teased from the dorsal root that was in continuity with the ligated spinal nerve. Electrical stimulation of sympathetic preganglionic fibers in T13 or L1 ventral root (50 Hz, 2-5 mA. 0.5 ms pulse duration, 10 sec) was made to see if the activity of recorded afferents was modulated. About half of afferents showing spontaneous discharges responded to sympathetic stimulation, and had the conduction velocities in the A-fiber range. Most of the sympathetically induced afferent responses were excitation. This sympathetically induced excitation occurred in the dorsal root ganglion (DRG), and was blocked by yohimbine (${\alpha}_2$ blocker), neither by propranolol ($\beta$ blocker) not by prazosine (${\alpha}_1$ blocker). The results suggest that after spinal nerve ligation, sympathetic efferents interact with sensory neurons having A-fiber axons in DRG where adrenaline released from sympathetic nerve endings excites the activity of sensory neurons by acting on 2-adrenoreceptors. This 2-adrenoreceptor mediated excitation of sensory neurons may account for sympathetic involvement in neuropathic pain.

• The Korean Journal of Physiology
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• 제29권2호
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• pp.309-321
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• 1995

In the present study, the relationship between the somatosympathetic reflexes and arterial blood pressure responses to electrical stimulation of the peripheral nerve was investigated in cats anesthetized with ${\alpha}-chloralose$. Single sympathetic postganglionic fiber activities were recorded from the hindlimb muscle and skin nerves and also from the cervical and abdominal sympathetic chains. Effects of the morphine on responses of the sympathetic nerve and arterial blood pressure to activation of the peripheral $A{\delta}-$ and C-afferent nerves were analyzed. The following results were obtained. 1) Arterial blood pressure was depressed by peripheral AS-afferent stimulation (A-response) and was elevated during C-afferent activation (C-response). 2) Intravenously administered morphine enhanced the C-response while the A-response decreased insignificantly, Only the C-response was decreased by intrathecal morphine. 3) All the ten recorded cutaneous sympathetic fibers showed periodic discharge pattern similar to respiratory rhythm and five of them also showed cardiac-related rhythm. However, most of the muscular sympathetic fibers had cardiac-related rhythm and only four fibers showed respiratory rhythm. 4) Morphine decreased the sympathetic C-reflex elicited by the peripheral C-afferent activation and the abdominal sympathetic A-reflex was also decreased by morphine. From the above results, it was concluded that supraspinal mechanisms were involved in the enhanced arterial pressor response to peripheral C-afferent activation by intravenous morphine.

• 한국식품영양과학회지
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• 제36권2호
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• pp.194-200
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• 2007

본 연구에서는 불용성 식이섬유인 셀룰로오스와 수용성 식이섬유인 펙틴이 식사성 열생성에 미치는 영향을 관찰하기 위하여 건강한 여자 대학생을 대상으로 식이섬유 제한식인 CD를 대조군으로 셀룰로오스식인 CED, 펙틴식인 PTD를 급식시켜 식후 3시간 동안의 DIT와 체온, 심박수를 측정하여 다음과 같은 결과를 얻었다. 대상자들의 나이는 평균 22.3 1.9세이었고, 신장과 체중은 각각 평균 $159.7{\pm}4.7cm$ 및 $52.5{\pm}8.6kg$이었다. 대상자들의 휴식대사량은 평균 $0.79{\pm}0.02kcal/min$이었다. 시간에 따른 DIT는 모든 실험식에서 식후 30분에 최고치를 나타내었다가 이후 감소하는 경향이었다. 실험식사 섭취 후 3시간 동안 측정한 DIT의 반응면적$(\Delta-AUC)$은 CD, CED 및 PTD가 각각 $59.77{\pm}2.66kcal,\;39.91{\pm}2.65kcal$ 및 $47.26{\pm}5.76kcal$를 기록하여 섭취한 열량의 $14.05{\pm}0.62%,\;9.33{\pm}0.62%$ 및 $11.07{\pm}1.35%$이었다. 식이섬유를 첨가한 실험군인 CED와 PTD가 CD에 비해 식후 3시간 동안의 DIT가 유의적으로 낮았으나, 식이섬유간 DIT는 유의적인 차이가 없었다. 실험식사 섭취 후 3시간 동안 측정한 체온의 반응면적$(\Delta-AUC)$은 실험식 간에 유의한 차이가 없었으나, 심박수로 측정한 교감신경계는 CD가 CED 및 PTD에 비하여 유의적으로 높았고, 식이섬유 간의 차이는 없었다. 이상에서와 같이 동량의 종류를 달리하여 제공한 셀룰로오스식과 펙틴식이 식후 열생성을 유의적으로 낮추었다. 그러나 대상자의 심박수, 체온, 체조성과 같은 제요인과의 상관성을 밝히지 못하여, 이의 기전을 밝히기 위한 추후 연구가 필요하다.