• The Korean Journal of Physiology
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• 제17권1호
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• pp.45-54
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• 1983

Contractile responses of myocardium and vascular smooth muscle to angiotensin II were studied in isolated rabbit papillary muscles and aortic helical strips, with respect to the sensitivity and the mechanism of action. All experiments were performed in $HCO-_3\;-buffered Tyrode solution which was aerated with $3%\;CO_2-97%\;O_2$ and kept pH 7.35 at $35^{\circ}C$. Action potentials were measured by conventional microelectrode technique in the papillary muscles. Helical strips of vascular smooth muscle were prepared from the descending thoracic aorta of the rabbit. Angiotensin II elicited a positive inotropic effect in doses from $10^{-8}$ to $10^{-6}\;M$, and this effect was dose-dependent and characterized by a symmetrical increase of maximum dP/dt during contraction and relaxation phase. Slow responses (or slow action potentials) were induced by A. II $(10^{-6}\;M)$ in the papillary muscle hypopolarized by 27 mM $K^+$. These A. II-induced slow action potentials were eliminated by verapamil (2 mg/l), but not affected by propranolol $(10^{-5}\;M)$. In aortic helical strips, contractile force was increased dose-dependently in the range of $10^{-10}{\sim}10^{-7}\;M$ A. II. $ED_{50}$ in aorta was $3{\times}10^{-9}\;M$ A. II, whereas that in paillary muscle was $2.5{\times}10^{-7}\;M$ A. II. A. II contracted vascular smooth muscle in depolarizing concentration of $K^+$ (100 mM $K^+$), and also produced a sustained contraction even in the presence of verapamil and regitine. The results of this experiment suggest that the primarily important physiological role of A. II is the action on the blood vessel, and the positive inotropic effect of A. II in papillary muscle results from the increase of slow inward $Ca^{++}$ current, and that A. II-induced contraction of aorta is independent of transmembrane potential and associated with promoting bet transmembrane $Ca^{++}\;-influx$ and the mobilization of cellular $Ca^{++}$.

• 대한약리학회지
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• 제13권2호
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• pp.1-9
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• 1977

최근 강심작용 약물로 보고된 부자 부타놀 분획의 가토 심방근에서의 자극빈도에 따른 강심효과를 분석한 결과는 다음과 같다. 1) 가토 심방근의 수축력은 자극빈도에 따라 polyphasic한 수축양상을 보였으며 rested-state contraction은 $120{\sim}400sec$의 interval에서 나타났으며 이후 10sec의 간격까지는 급격한 수축력의 감소를 보이는, 축적NIEA가 PIEA의 양을 능가하는 양상을 보였으며 이 이하의 자극 빈도에서는 수축력의 증가를 보였고 대부분 0.25 sec이하의 빈도의 자극으로는 수축력의 감소를 보였다. 2) Ouabain은 저 농도에서는 interval-strength curve에 대하여 rested-state contraction의 증가와 전 자극빈도에서 비슷한 수축력의 증가를 나타내었으며, 고농도에서는 rested-state contraction의 증가와 축적 NIEA의 소멸 속도를 증가시켰으나 이는 rested-state contraction을 나타내는 시간의 단축에 따른 이차적 효과로 판정하였다. 또한 ouabain 자극빈도에 따른 강심 효과의 양상은 세포외 calcium 농도를 증가시킨 때와 유사한 양상이었다. 3) Norepinerhrine은, rested-state contraction에는 거의 영향을 주지 않았으며, 고 빈도에서 더욱 현저한 강심 작용을 나타내었고 축적 PIEA의 양의 증가와 매 beat 당 산출하는 PIEA의 양의 증가를 나타내었다. 4) 부자 부타놀 분획은 norepinephrine과 유사하고 빈도에서 수축력의 증가가 현저 하였으며, 수축력의 증가는 용량 반응 상관을 보였으며, PIEA 축적량 및 매 beat 당 산출하는 PIEA를 증가 시켰다. 따라서 고빈도에서의 강력한 수축력의 증가는 PIEA에 대한 효과에 의할 것으로 사료하였다.

• 대한약리학회지
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• 제22권2호
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• pp.96-104
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• 1986

최근에 미나라아제비과 (Ranunculaceae)에 속하는 부자(Aconiti tuber)로부터 강심작용을 나타내는 성분을 분리하여 Higenamine이라 명명하였고 그 작용기전을 밝히려는 시도가 활발히 진행되고 있다. 그러나 생약제로 부터 얻을 수 있는 Higenamine은 극히 미량이고 그 과정 또한 복잡하다. 따라서 본 연구에서는 유효성분을 대량 얻기 위한 방법으로서 전합성(total Synthesis)을 시도하였으며 IR, UV, NMR 및 elemental 분석등을 통하여 합성된 물질을 확인하였으며 가토에 대하여 in vivo에서 혈압, 심박동수, 호흡 및 말초저항에 미치는 영향과 아울러 in vitro에서 심근수축 증강작용(positive inotropic action) 및 심박속도 증강작용(positivechronotropic action)을 관찰 분석하여 다음과 같은 결론을 얻었다. 1) Higenamine은 $1-10\;{\mu}g/kg/min$ 정맥주사시 수축기 및 이완기혈압 모두를 용량 의존적으로 하강시켰고 후자가 전자보다 더욱 현저하였으며 호흡은 촉진되었고 말초 혈류량은 증가되었으나 심박동수는 영향이 없었다. 2) 혈압에 대한 Higenamine의 작용은 propranolol 전처치에 의하여 억제되었다. 3) Higenamine의 catechol핵과 커다란 아미노기는 베타 수용체기 대하여 전자는 활성을 후자는 친화력과 관계있을 것으로 추정하였다. 이상의 결과 Higenamine은 adrenergic ${\beta}$-수용체에 작용하여 그 작용을 발휘하는 것으로 사료 되었다.

• 대한수의학회지
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• 제33권2호
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• pp.199-209
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• 1993

The effects of ${\alpha}_1$-adrenergic stimulation on membrane potential, intracellular sodium activity $(a_N{^i{_a}})$, and contractility were investigated in the isolated papillary muscle of euthyroid, hyperthyroid, and hypothyroid guinea pigs. Cardiac alterations in the thyroid state have been shown to induce marked changes in action potential characteristics, the most pronounced shortening of action potential duration by hyperthyroidism and an increase in duration by hypothyroidism. $10^{-5}M$ Phenylephrine produced a decrease in $(a_N{^i{_a}})$ in euthyroid and hypothyroid preparations, but an increase in $(a_N{^i{_a}})$ in hyperthyroid ones. The major findings were that phenylephrine produced a stronger positive inotropic effect(PIE) without initial negative inotropic effect(NIE) in hyperthyroid preparations, while phenylephrine produced markedly NIE in hypothyroid ones. The alterations in membrane potential, $(a_N{^i{_a}})$, and contractility were abolished by $3{\times}10^{-5}M$ prazosin in hypothyroidism. In hypothyroid ventricular muscle, the decrease in $(a_N{^i{_a}})$ caused by phenylephrine were not abolished or reduced by $10^{-5}M$ strophanthidin, $10^{-5}M$ TTX, $3{\times}10^{-4}M$ lidocaine, or $100^{-5}M$ verapamil. These results indicate that the ${\alpha}_1$-adrenoceptor-mediated decrease in $(a_N{^i{_a}})$ is not associated with a stimulation of the $Na^+$-$K^+$ pump, inhibition of the $Na^+$ or $Ca^+$ channel in hypothyroid ventricular muscle. $10^{-5}M$ Phenylephrine decreased $(a_N{^i{_a}})$ but increased $(a_N{^i{_a}})$ in the presence of a PKC activator phorbol dibutyrate$(PDB_u)$. In conclusion, it is suggested that the following sequence of events in response to phenyleplhane occur in guinea pig ventricular muscle. First, changes in thyroid state may contribute to the ventacular electrophysiological propeties or ion transport system. Second, the adrenoceptor-mediated initial transient NIE may be associated with the decrease in $(a_N{^i{_a}})$ by PKC activation.

• Natural Product Sciences
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• 제5권1호
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• pp.25-32
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• 1999

The pharmacological actions of ambrein were investigated alone or in combination as a pretreatment with agonists (adrenaline, noradrenaline, acetylcholine, histamine, nicotine), antagonists (atropine, atenolol) and calcium channel blocker (verapamil) in vivo in anaesthetized SWR rats using blood pressure, heart rate and myocardial contractility as parameters. Ambrein in the dose range of 50-200 mg/kg to the normotensive anaesthetized rats demonstrated negative chronotropic effect and increased the myocardial contractility significantly. At the mid dose (100 mg/kg) this increase in contractile force was 36% and 44% above the normal at 30 min and 60 min intervals post-treatment, respectively. Both of the lower and high doses (50 mg/kg and 200 mg/kg) had similar effects. Furthermore, this contractile response was dose related. Also, this compound produced a considerable increase in myocardial contractility when used as a pretreatment with some agonists and antagonists. The results on blood pressure did not show a considerable change when ambrein was used alone. However, ambrein pretreatment at the dose of 100 mg/kg did not block the effects of adrenaline, noradrenaline, isoprenaline and acetylcholine on heart rate and blood pressure. On the other hand, this pretreatment attenuated the sympathoadrenal effects of nicotine significantly. Chronotropic and blood pressure changes produced by histamine were also inhibited by ambrein pretreatment. This pretreatment significantly reversed the effects of atenolol but failed to demonstrate any change in the negative chronotropic, inotropic and hypotensive responses induced by verapamil. It is concluded that ambrein induced nonselective dose dependent antagonism of the effects of some agonists and antagonists require contribution of some neuromediators. However, the positive isotropic effects of ambrein possibly involve the enhancement of slow Ca channels and/or activation of ${\beta}-adrenergic$ receptors in the heart. At this moment it is difficult to explain the exact mode of action of ambrein and the studies dealing with Ca channel blocker and adrenergic blocker followed by ambrein may help to define the factors which contribute to its positive inotropic effects.

• 대한약리학회지
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• 제13권2호
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• pp.11-17
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• 1977

흰쥐 적출 좌심방근을 사용하여 부자 부타놀 분획의 강심작용의 potassium-dependency 여부를 기존 강심제인 ouabain을 대조 약물로 하여 검토한 결과는 다음과 같다. 1) 흰쥐 적출 좌심방근은 ouabain에 대해서는 가토 등의 실험 동물에 비해 현저한 내성을 보였다. 2) 심방근의 수축장력은 세포의 potassium 농도를 2mM에서 10mM까지 변화 시켰을때 유의한 수축력의 변화를 볼 수 없었다. 3) Potassium 2mM에서의 ouabain의 강심 효과는 6, 10mM에서 보다 현저한, 즉 potassium dependent한 강심 효과를 나타내었으나, 부자 부타놀 분획의 강심효과는 potassium-independent한 양상이었다. 4) 흰쥐 심방근의 흥분성은 생리적 potassium 농도인 6mM에서 가장 높았고 저 농도 및 고농도에서는 흥분성의 감소를 보였으며 본 실험에 사용된 ouabain $2{\times}10^{-5}M$, 부자 부타놀 분획 $5{\times}10^{-4}gm/ml$의 농도는 심방근 흥분성에 별 영향을 주지 못했다.

• 대한약리학회지
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• 제20권1호
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• pp.55-65
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• 1984

[$PGF_{2{\alpha}}$]의 rat적출심방에 대한 작용을 ouabain의 작용과 비교하여 다음과 같은 결과를 얻었다. $PGF_{2{\alpha}}$의 양성변력성작용은 ouabain의 작용에 비해 potency가 강하고 efficacy는 낮았다. Ouabain은 $PGF_{2{\alpha}}$의 양성변시성작용과 유사한 양성변시성 경향을 나타내었는데 이 점에 대해 추후의 탐구가 요구된다. $PGF_{2{\alpha}}(3{\pm}10^{-8}M)$의 작용은 저칼슘농도(1.4mM)에서 ouabain$(3{\pm}10^{-3}M)$보다 현저히 $({\leq}0.05{\sim}p{\leq}0.00)$강하게 나타났고, medium내에 첨가되는 $Ca^{++}$에 대하여도 보다 예민하게 반응하였다. 저칼륨 medium(2.8mM) 또는 medium내 $K^+$첨가는 $PGF_{2{\alpha}}$보다 ouabain의 작용에 더 큰 영향을 미쳤다. $PGF_{2{\alpha}}$와 ouabain의 작용에 미치는 lidocaine ($1{\pm}10^{-5}M$이상의 고농도)의 영향은 매우 흡사하여 별다른 차이점을 볼 수 없었다. Propranolol $(3{\pm}10^{-6}M)$로써 전처치하여 아드레나린성 ${\beta}$수용체를 봉쇄한 적출심방에서 $PGF_{2{\alpha}}$ 양성변력성 및 양성변시성 작용은 방해를 받지 않았다. 이상의 결과로 보아 $PGF_{2{\alpha}}$는 ouabain의 $Na^+$, $K^+$-ATPase 억제기전파는 달리 $PGF_{2{\alpha}}$ 고유의 막수용체에 작용하여 $Ca^{++}$의 세포내 유입을 촉진시키는 기전으로 작용하는 것으로 추측되며, 그 수용체의 등정(identification)은 추후의 연구과제로 남는다.

• 생약학회지
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• 제13권4호
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• pp.137-144
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• 1982

It was previously reported from our laboratory that the rate of deterioration of the force of contraction was slower in heart from Panax ginseng extract treated rats. The study carried out to elucidate its mechanism of the action on hearts. The cyclic AMP content in the rat hearts was measured by the method of radioimmunoassay techniques. Panax ginseng extract (100mg/kg/day) was administered orally to male Sprague-Dawley rats weighing 150g to 250g for 1 week and after 24 hrs the hearts were isolated and the cyclic AMP content in the fresh heart was assayed. The difference in cyclic AMP content between the rats treated with Panax ginseng extracts and normal rats was not significant. Panax ginseng extract(l00mg/kg/day) was administered orally to the rats for I week and after 24 hrs the hearts were isolated and perfused with Krebs-Henseleit buffer (pH7.4) for 90min. The cyclic AMP content in the both treated and normal rats was not also significantly different. On the other hand, when total ginseng saponin (50mg/kg/day) was administered orally to rats for 1 week and after 24 hrs, the isolated hearts were perfused with Krebs Henseleit solution for 32min, the cyclic AMP content in total ginseng soponin treated hearts was decreased by 18.7% compared to normal rats. It was also observed that when isolated hearts were perfused with total ginseng saponin $(10^{-4}g/ml)$ for 12 min after 30 min equilibration period, the cyclic AMP content in total ginseng saponin treated hearts was decreased by 23.7% compared to normal rats. Isolated hearts were perfused with ginseng saponins $(10^{-4}g/ml)$ or with Krebs-Henseleit solution alone for 10min and subsequently with dl-isoproterenol $(1/2{\times}10^{-6}M)$ until the positive inotropic effect of isoproterenol was initiated. The cyclic AMP content in each rat hearts treated with total ginseng saponin, or with ginsenoside $Rb_1$, or with Krebs-Henseleit solution alone were increased by 35.5%, 42.4%, 47.5%, respectively, compared to normal rats.

• 척추신경추나의학회지
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• 제16권2호
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• pp.47-54
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• 2021

Objectives This review was conducted to study use of Aconitum herbal medicine for pain control in musculoskeletal disease. Methods Musculoskeletal disease is a major factor of social cost increase and physical disability. Various drugs, surgery and imaging are being overused regardlessly. Aconitum herbal plants are one of the most toxic Korean traditional herbs. However, they could be utilized effectively on patients with appropriate processing and decocting time. We searched Korean medicine literature to see various features of aconitum herbal plants and tried to find the utilization of the plants in effective way for pain control in musculoskeletal disease. Results Aconitum herbal plants needs to be used carefully because of intoxication which could lead to severe damage to human body. Processing of these toxic plants could minimize the harm and raise the benefits, such as relieving various types of pain and positive inotropic action. Further studies with clearer evidence and discovering aftereffects of processing in more details are needed. Conclusions Aconitum herbal plants could dedicate to controlling pain in musculoskeletal disease with various forms and appropriate processing.

• 대한약리학회지
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• 제12권1호
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• pp.23-29
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• 1976

최근(最近) 현저한 심근수축증강작용(心筋收縮增强作用)이 알려져 있는 부자(附子) ${\ulcorner}$부타놀${\lrcorner}$ 분획의 작용기전(作用機轉)을 구명(究明)코저 하는 시도(試圖)의 일환으로 심근수축단백(心筋收縮蛋白)에 대한 직접적인 영향을 관찰하였다. 부자${\ulcorner}$부타놀${\lrcorner}$ 분획은 actomyosin ATPase 활성(活性)에 대하며 별(別) 영향을 미치지 않았으며 actin-myosin 상호결합(相互結合)에서 $Ca^{++}$과 유사한 역활을 나타내지도 못했다. 단 actomyosin의 superprecipitation에 대하여는 약간 촉진적(促進的)이었으나 이러한 작용은 actomyosin ATPase 활성(活性)의 증가를 동반치 못했다. 그러나 microsmal $Na^+-K^+$-activated ATPase 활성(活性)은 현저히 억제하였으며 이러한 현상은 부자(附子)${\ulcorner}$부타놀${\lrcorner}$ 분획이 $Ca^{++}$의 membrane transport에 영향을 미칠것으로 인정되는 사실로서 부자(附子)${\ulcorner}$부타놀${\lrcorner}$ 분획의 심근수축증강작용기전(心筋收縮增强作用機轉)의 일부는 근수축단백(筋收縮蛋白)에 대한 직접작용보다는 extracellular 또는 intracellular membrane에서의 $Ca^{++}$ 이동에 영향을 미쳐 세포내 유리 $Ca^{++}$농도를 증가시키는것이 간접적으로 심근수축(心筋收縮)을 촉진(促進)시킬 것으로 사료되었다.