• 대한의용생체공학회:의공학회지
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• 제12권3호
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• pp.177-184
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• 1991

Characteristics of the lung inflation and deflation reflexes were measured at various temperatrues on the cervical vagi in five anesthetized mongrel dogs. Nerve temperature was maintained at the body temperature, and $2-14^{\circ}C$ with $2^{\circ}C$ apart using a specially designed automated vagal cooling apparatus with an accuracy to within ${\pm}0.1^{\circ}C$ at each temperature. The inflation reflex was blocked abruptly at $8-10^{\circ}C$. The deflation reflex started weakened at $14^{\circ}C$, thereafter showed a gradual blockade with the temperature decreased with a substantial variance among the animals. It was approximately 75% blocked at $2-6^{\circ}C$. These differences in temperature characteristics made it hard to differentiate the deflation reflex from the inflation reflex. In one animal, however, the inflation reflex was completely blocked with the deflation reflex almost alive at $6-8^{\circ}C$. This suegests that differential cold blockade of the vagal reflexes can be done only in selected subjects. Fur- thermore, the fact that these two reflexes were blocked at different temperatures may be due to the differences in the nerve fiber size and the changes in the conduction velocity with temperature.

• 대한의용생체공학회:의공학회지
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• 제4권1호
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• pp.3-8
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• 1983

Characteristics of the lung inflation and deflation reflexes were measured at various temperatures on the cervical vagi in five anesthetized mongrel dogs. Nerve temperature was maintained at the body temperature, and 2-14˚C with 2˚C apart using a specially designed automated vagal cooling apparatus with an accuracy to within $\pm$ 0.1˚c at each temperature. The inflation reflex was blocked abruptly at 8-10˚C. The deflation reflex started weakened at 14˚C, thereafter showed a gradual blockade with the temperature decreased with a substantial variance among the animals.It was approximately 75% blocked at 2-5˚C. These differences in temperature characteristics made it hard to differentiate the deflation reflex from the inflation reflex. In one animal, however, the inflation reflex was completely blocked with the deflation reflex almost alive at 6-8˚C. This suggests that differential cold blockade of the vagal reflexes can be done only in selected subjects. Furthermore, the fact that these two reflexes were blocked at different temperatures may be due to the differences in the nerve fiber size and the changes in the conduction velocity with temperature.

• The Korean Journal of Physiology
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• 제17권1호
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• pp.23-28
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• 1983

steroid가 폐절제에 의한 대상성증식기의 폐장의 압력-용적곡선에 어떤 영양을 미칠 것인가를 알아보기 위해 실시한 본 실험의 결과를 요약하면 폐절제군은 대조군에 비해 폐용압률이 증가하였고 폐절제후 반대측폐장의 무게는 대조군에 비해 폐절제군이 유의하게 증가하였고 폐절제후 betamethasone을 투여한 군에 있어서는 대조군에 비해서는 증가하였으나 폐절제군보다는 적게 증가하였다. 또한 이러한 결과들은 betamethasone에 의해 폐포표면활성물질의 분비가 증가하였거나 혹은 betamethasone이 폐장실질의 결합조직의 단백대사에 영향을 미쳐 elastic recoil force가 감소하여 생긴 결과라고 생각된다.

• The Korean Journal of Physiology
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• 제27권1호
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• pp.37-49
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• 1993

Ventilatory responses to inhaled $CO_2$ were measured during continuous negative pressure breathing (CNPB) in awake dogs. End expiratory lung volume (EELV) decreased linearly with pressure level during CNPB (correlation coefficient= 0.81, p<0.005) during air breathing. When CNPB was applied during 5% $CO_2$ inhalation, the decrease in EELV was not significantly different (p<0.5) from that during air breathing. As a result of a lowered EELV, tidal volume ($V_T$) significantly decreased by 22% and breathing frequency ($f_B$) increased by 68% in the steady state during air breathing (p<0.0001). These responses were similar during 5% $CO_2$ inhalation, thus the $CO_2$ response curve measured during CNPB shifted upward without a change in sensitivity (p>0.05). These results indicate additive effects of CNPB and $CO_2$ inhalation. The degree of hyperventilation during CNPB at eupnea was estimated to be 63% of that during control ventilation and was significantly greater than zero (p<0.0001), which suggests an alveolar hyperventilation due to CNPB. These results suggest that the mechanical alterations associated with n decrease in lung volume could play an important role in ventilatory control independently of chemical regulation of breathing. Thus, exercise hyperpnea, which is associated with a lowered functional residual capacity (FRC), may in part be explained by this mechanical stimulation of breathing.

• Journal of Chest Surgery
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• 제7권1호
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• pp.1-8
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• 1974

Acute pulmonary edema was induced by intravenous injection of epinephrine, intravenous infusion of dextran and intratracheal instillation of acid solution index was determined from pressure volume curves in excised lungs. Surface activity was also investigated with measurements of maximum and minimum surface tension and stability index on saline extracts of same lungs. The results were as follows. 1. The expansion index of excised lung in which pulmonary edema was induced by intravenous injection of epinephrine, intravenous infusion of dextran and intratracheal instillation of acid solution was ignificantly decreased as compared with the normal control of $0.86{\pm}0.017$ to $0.74{\pm}0.03$, $0.71{\pm}0.081$and $0.76{\pm}0.02$, respectively. 2. The deflation curves of excised lungs in which pulmonary edema was induced were significantly decreased as compared with the normal controls. 3. The minimum surface tension of excised lung in which pulmonary edema was induced was significantly increased in each groups and stability index was significantly decreased as compared with the normal controls 0.78 to $0.35{\pm}0.039$, $0.29{\pm}0.02 $ and $0.31{\pm}0.083$, respectively. 4. The decrease of pulmonary surface activity in acute pulmonary edema was in proportion to the degree of pulmonary edema regardless of their etiology.

• The Korean Journal of Physiology
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• 제8권2호
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• pp.49-53
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• 1974

제 II 형(第 II 型) 폐포세포(肺胞細胞)의 페포표면활성물질(肺胞表面活性物質) 분비기능(分泌機能)이 부교감신경성작용(副交感神經性作用)에 의(依)해서 영향(影響)을 받을 것인지를 구명(究明)하기 위해서 체중(體重) 매(每) kg 당(當) 0.5mg의 pilocarpine hydrochloride를 투여(投與)한 가토(家兎)에서 폐장(肺臟)의 압력(壓力)-용적곡선(容積曲線)및 폐세척액(肺洗滌液)의 표면활성도(表面活性度)를 측정(測定)한 결과(結果)는 다음과 같다. (1) 적출가토폐(摘出家兎肺)에 공기(空氣)를 주입(注入) 및 배출(排出)할 때의 압력(壓力)-용적곡선(容積曲線)은 정상(正常) 가토(家兎)의 그것보다 hysteresis현상(現象)이 더욱 심(甚)하였으며 특(特)히 배출곡선(排出曲線)이 좌측(左側)으로 편입(偏入)되어있었다. (2) 정상(正常) 가토폐세척액(家兎肺洗滌液)의 평균최대(平均最大) 및 최소표면장력(最小表面張力) 및 stability index는 각각(各各) 46.6 dyne/cm, 7.4 dyne/cm 및 1.5이었다. (3) Pilocarpine 투여가토폐세척액(投與家肺洗滌液)의 평균최대(平均最大) 및 최소표면장력(最小表面張力) 및 stability index는 각각(各各) 47.5 dyne/cm, 6.1 dyne/cm 및 1.5로서 최소표면장력(最小表面張力)은 감소(減少)하는 경향(傾向)을 보였다. (4) 이상의 실험결과(實驗結果)로 미루어 보아 pilocarpine 투여(投與)에 의(依)해서 제 II 형(第 II 型) 폐포세포(肺胞細胞)의 페포표면활성물질(肺胞表面活性物質)의 분비기능(分泌機能)이 증가(增加)되는 경향(傾向)을 보였다.

• The Korean Journal of Physiology
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• 제15권1호
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• pp.27-36
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• 1981

Alcohol 의 급성중독(急性中毒)으로서 폐기능중(肺機能中) 특(特)히 폐용압률(肺容壓率)과 폐포활성물질(肺胞活性物質)(surfactant)의 변화(變化)를 살펴봄으로써 alcohol 이 폐기능(肺機能) 또는 폐대사(肺代謝)에 미치고 효과(效果)의 일단(一端)을 알기 위(爲)하여 흰쥐를 재료(材料)로 하여 50% alcohol 을 체중(體重) 100 gm 당(當) 1.5 ml 씩 경구적(經口的)으로 단회투여(單回投與)하여 급성(急性) Ethyl alcohol 중독(中毒)을 일으켰다. Alcohol 중독과정(中毒過程)에서 24 시간(時間)까지 경시적(經時的)으로 혈중(血中) alcohol 농도(濃度)와 hematocrit(Hct)치(値)를 측정(測定)하고, 폐용압률(肺容壓率) 및 surfactant 중(中)의 단백량(蛋白量)과 무기인(無機燐)(Pi)를 측정(測定)하여, 정상군(正常群)과 비교(比較)하여 다음과 같은 결과(結果)를 얻었다. Alcohol 혈중농도(血中濃度)는 정상치(正常値)인 $0.17{\pm}0.01\;gm%$(평균(平均)${\pm}$표준오차(標準誤差) 이하동일(以下同一))에 비(比)하여 중독(中毒) 1시간(時間)에서 $0.71{\pm}0.02\;gm%$로 최고치(最高値)에 달(達)하고, 그후(後) 차차(次次) 낮아져서 24 시간(時間)에서는 $0.36{\pm}0.02\;gm%$이었으나, 전실험치(全實驗値)는 정상(正常)에 비(比)해서는 유의(有意)하게 높았다. Hct 치(値)는 1시간(時間)에서 $64.86{\pm}2.45%$로서 최고치(最高値)를 나타내었고, 그후(後) 계속(繼續) 정상치(正常値)인 $48.87{\pm}0.28%$에 비(比)하여 유의(有意)하게 높은 값을 유지(維持)하였다. 폐중량대(肺重量對) 체중비(體重比)(L/B 비(比))는 중독(中毒) 3시간(時間)부터 $5.49{\pm}0.61$로서 정상치(正常値)인 $7.57{\pm}0.56$에 비(比)하여 유의(有意)하게 낮아지고, 24시간(時間)까지 유의(有意)한 감소(減少)를 나타내었다. 폐용압률(肺容壓率)은 확대(擴大)(inflation)와 축소(縮小)(deflation)에서 모두 3시간(時間)까지 정상(正常)과 큰 차이(差異)가 없었으나, 6및 12 시간(時間)에서는 증가(增加)된 값을 나타내었고, 특(特)히 12 시간(時間)에서는 유의(有意)하게 높은 값을 나타내었다가, 24시간(時間)에는 정상(正常)에 가까워지는 경향(傾向)을 나타내었다. 폐세척액(肺洗滌液)의 단백량(蛋白量)은 정상(正常)의 $10.65{\pm}0.62\;mg/gm$에 비(比)하여 3시간(時間)에서 $12.36{\pm}0.35\;mg/gm$, 12시간(時間)에서 $12.70{\pm}0.74\;mg/gm$ 및 24시간(時間)에서는 $12.65{\pm}0.88\;mg/gm$로서 유의(有意)하게 높은 값을 나타내었고, Pi치(値)도 중독(中毒) 6시간(時間)부터는 높은 값을 나타내었으며, 특(特)히 12 시간(時間)에서는 $7.65{\pm}0.63\;{\mu}mol/gm$, 24시간(時間)에서는 $6.70{\pm}0.36\;{\mu}mol/gm$로서, 정상(正常)의 $5.32{\pm}0.20\;{\mu}mol/gm$에 비(比)하여 유의(有意)하게 높은 값을 나타내었다. 한편, 폐추출액(肺抽出液)의 단백량(蛋白量)은 1및 3시간(時間)에서 낮은 값을 나타내었으나, 대체(大體)로 정상(正常)과 비슷한 경향(傾向)을 나타내었고, Pi 치(値)는 대체(大體)로 높은 양상(樣相)을 나타내었으며, 특(特)히 중독(中毒) 6, 12 및 24 시간(時間)에서는 각각(各各) $17.77{\pm}1.54\;{\mu}mol/gm$, $13.92{\pm}0.78\;{\mu}mol/gm$ 및 $14.57{\pm}5.53\;{\mu}mol/gm$로서, 정상(正常)의 $10.34{\pm}0.37\;{\mu}mol/gm$에 비(比)하여, 모두 유의(有意)하게 높은 값을 나타내었다. 이상(以上)의 결과(結果)로서 alcohol 급성중독(急性中毒)에서는, surfactant 의 활성도(活性度)나 폐용압률(肺容壓率)이 증가(增加)되어 폐기능(肺機能)에 변화(變化)가 초래(招來)된다고 하겠다.