• The Korean Journal of Physiology and Pharmacology
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• 제13권5호
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• pp.361-365
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• 2009

Effects of quercetin, a kind of flavonoids, on the vasodilating actions were investigated. Among the mechanisms for quercetin-induced vasodilatation in rat aorta, the involvement with the $Ca^{2+}$ activated $K^+$ ($K_{Ca}$) channel was examined. Pretreatment with NE ($5\;{\mu}M$) or KCl (60 mM) was carried out and then, the modulation by quercetin of the constriction was examined using rat aorta ring strips (3 mm) at $36.5^{\circ}C$. Quercetin (0.1 to $100\;{\mu}M$) relaxed the NE-induced vasoconstrictions in a concentrationdependent manner. NO synthesis (NOS) inhibitor, NG-monomethyl-L-arginine acetate (L-NMMA), at $100\;{\mu}M$ reduced the quercetin ($100\;{\mu}M$)-induced vasodilatation from $97.8{\pm}3.7%$ (n=10) to $78.0{\pm}11.6%$ (n=5, p<0.05). Another NOS inhibitor, L-NG-nitro arginine methyl ester (L-NAME), at $10\;{\mu}M$ also had the similar effect. In the presence of both $100\;{\mu}M$ L-NMMA and $10\;{\mu}M$ indomethacin, the quercetin-induced vasodilatation was further attenuated by $100\;{\mu}M$ tetraethylammonium (TEA, a $K_{Ca}$ channel inhibitor). Also TEA decreased the quercetin-induced vasodilatation in endothelium-denuded rat aorta. Used other $K_{Ca}$ channel inhibitors, the quercetin-induced vasodilatation was attenuated by $0.3\;{\mu}M$ apamin (a SK channel inhibitor), but not by 30 nM charybdotoxin (a BK and IK channel inhibitor). Quercetin caused a concentration-dependent vasodilatation, due to the endotheliumdependent and -independent actions. Also quercetin contributes to the vasodilatation selectively with SK channel on smooth muscle.

• 대한수의학회지
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• 제43권4호
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• pp.573-578
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• 2003

The effects of removing the endothelium on the vasodilatory response to substance P, calcitonin gene-related peptide (CGRP), and vasoactive intestinal peptide (VIP) was examined in the isolated rabbit renal artery. The vasodilator response to substance P ($0.1{\mu}M$) was completely absent in vessels in which the endothelium had previously been removed. There was no significant difference in the vasodilatation produced in response to CGRP ($0.1{\mu}M$), or VIP ($0.1{\mu}M$) in the intact and removed-endothelium rabbit renal artery segments. L-NAME ($100{\mu}M$) significantly reduced the vasodilatory response to substance P ($0.1{\mu}M$). This inhibition was significantly attenuated when L-arginine (10 mM) was also present in the organ bath along with L-NAME ($100{\mu}M$). Indomethacin ($1{\mu}M$) did not significantly affect the vasodilatation produced in response to substance P ($0.1{\mu}M$). The inhibitory effect of L-NAME ($100{\mu}M$) and indomethacin ($1{\mu}M$) on the vasodilatory response to substance P ($0.1{\mu}M$) was not significantly different from that produced by L-NAME ($100{\mu}M$) alone. This study indicates that substance P induced vasodilatation via an endothelium-dependent mechanism in the isolated rabbit renal artery. It also established that CGRP and VIP induced vasodilatation by an endothelium-independent mechanism and substance P-induced vasodilatation is at least partially via NO.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2023년도 임시총회 및 춘계학술대회
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• pp.39-39
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• 2023

The purpose of this study is to investigate vasodilatation effect of complex saponin separated from Scrophulariae radix, Asparagus cochinchinensis and Liriope platyphylla mixture extract on rabbit carotid artery. In this study, to determine vasodilatation effect of complex saponin separated from Scrophulariae radix, Asparagus cochinchinensis and Liriope platyphylla mixture extract on rabbit carotid artery, arterial rings with intact or damaged endothelium were used for experiment using organ bath, and were contracted by endothelin. complex saponin, major active constituents of Scrophulariae radix, Asparagus cochinchinensis and Liriope platyphylla mixture extract, showed a moderate vasodilatation effect on the basilar arteries of rabbits. Therefore, treatment with complex saponin separated from Scrophulariae radix, Asparagus cochinchinensis and Liriope platyphylla mixture extract may selectively accelerate cerebral blood flow through dilatation of the basilar artery. Theseis result suggest a potential role of complex saponin separated from Scrophulariae radix, Asparagus cochinchinensis and Liriope platyphylla mixture extract as source of vasodilatation agent.

• The Korean Journal of Physiology and Pharmacology
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• 제2권4호
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• pp.471-477
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• 1998

Cyclosporin A (CsA), a widely used immunosuppressant, is well known to cause nephrotoxicity and hypertension as major side effects. The present study was aimed at investigating the effects of CsA-pretreatment on the activities of cytosolic guanylate cyclase (cGC) in relation to the alteration of relaxant responses in the rat thoracic aorta. CsA $(10\;{\mu}M)-preincubation$ for 90 min significantly attenuated the vasodilatation induced by sodium nitroprusside (SNP), a cytosolic guanylate cyclase activator, shifting the dose-response curve to the right. The increase in cGMP contents induced by SNP was markedly attenuated by CsA. SNP ($1\;{\mu}M{\sim}\;mM$) increased the cGC activity dose-dependently, and the increase was completely abolished by CsA. CsA attenuated the SNP-induced cGC activation dose-dependently. The abolishing effect of CsA-pretreatment on the SNP-induced cGC activation was not affected by washing the preparation, suggesting that the inhibition is irreversible. When CsA was added simultaneously with SNP, cGC activation was not attenuated. 1-(5-isoquinolinylsulfonyl)-2-methyl piperazine (H-7), a protein kinase C (PKC) inhibitor, decreased SNP-induced cGC activation and blocked the CsA-attenuation of cGC activation. These results suggest that CsA directly inhibits cGC participating in the CsA-induced impairment of vasodilatation, and that PKC is involved in the inhibitory action of CsA on cGC.

• 대한약리학회지
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• 제31권3호
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• pp.285-290
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• 1995

이 실험은 여러 파장$(240{\sim}520\;nm)$의 자외선 또는 가시광선(이후 '광선'이라 표기함)을 흰쥐흉부대동맥에 조사하여 이때의 혈관장력의 변화 및 조직내 cyclic GMP농도의 변화를 관찰하기위하여 시행하였다. 돼지관상동맥 또는 흰쥐 흉부대동맥의 환상표본에 spectrofluorometer의 xenon lamp를 이용하여 여러 파장의 광선을 조사하고 이때의 장력변동을 polygraph상에 기록하였다. Cyclic GMP농도변화는 표본에 광선을 조사한 직후 조직을 얼리고 homogenization 및 원침시킨 후 상청액을 ether로 추출하여 RIA kit로 측정하였다. Phenylephrine으로 수축된 내피존재 흰쥐 흉부 대동맥에서는 광선조사로 수축반응을 보였고 320 nm에서 최대수축반응을 일으켰다. 그 이상의 파장에서는 점차 수축반응이 감소되어 420 nm에서는 최대 이완반응을 일으킨 후 점차 기본장력으로 회복되었다. 그러나 내피제거 표본에서는 전파장에서 이완반응만을 일으켰고 이때 최대 이완반응은 370 nm에서 관찰되었다. 내피존재 표본에서 320, 380 및 420 nm의 광선을 30초간 조사한 결과 380과 420nm에서 현저한 cyclic GMP의 증가가 관찰되었으나 320 nm에서는 유의한 변동이 없었다. 한편, 내피제거 표본에서는370 nm의 광선조사로 cyclic GMP함량이 약 4배 증가하였다. 이상의 성적으로부터 흰쥐 흉부대동맥은 광선조사에 의하여 내피존재 표본에서는 수축-이완의 이상성반응을, 제거표본에서는 이완반응만을 일으키고 양 표본의 이완반응은 nitric oxide-cyclic GMP계의 활성화에 기인하나 수축반응은 cyclic GMP계와 직접 관련성이 없는 것으로 추론하였다.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.709-715
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• 2005

The purpose of this study was to investigate the effect of atropine on peripheral vasodilation and the mechanisms involved. The isometric tension of rat mesenteric artery rings was recorded in vitro on a myograph. The results showed that atropine, at concentrations greater than 1$\mu$M, relaxed the noradrenalin (NA)-precontracted rat mesenteric artery in a concentration-dependent manner. Atropine-induced vasodilatation was mediated, in part, by an endothelium-dependent mechanism, to which endothelium-derived hyperpolarizing factor may contribute. Atropine was able to shift the NA-induced concentration-response curve to the right, in a non-parallel manner, suggesting the mechanism of atropine was not mediated via the ${\alpha}_1$-adrenoreceptor. The $\beta$-adrenoreceptor and ATP sensitive potassium channel, a voltage dependent calcium channel, were not involved in the vasodilatation. However, atropine inhibited the contraction derived from NA and $CaCl_2$ in $Ca^{2+}$-free medium, in a concentration dependent manner, indicating the vasodilatation was related to the inhibition of extracellular $Ca^{2+}$ influx through the receptor-operated calcium channels and intracellular $Ca^{2+}$ release from the $Ca^{2+}$ store. Atropine had no effect on the caffeine-induced contraction in the artery segments, indicating the inhibition of intracellular $Ca^{2+}$ release as a result of atropine most likely occurs via the IP3 pathway rather than the ryanodine receptors. Our results suggest that atropine-induced vasodilatation is mainly from artery smooth muscle cells due to inhibition of the receptor-mediated $Ca^{2+}$-influx and $Ca^{2+}$-release, and partly from the endothelium mediated by EDHF.

• 한국자원식물학회지
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• 제33권5호
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• pp.467-475
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• 2020

고혈압은 성인의 수축기 혈압이 140 mmHg 이상이거나 이완기 혈압이 90 mmHg 이상일 때를 의미하며 고혈압은 뇌졸중, 신부전 및 관상동맥질환 등 인체 전반에 걸쳐 다양한 합병증을 일으키며 고혈압 유병자의 생명과 건강을 직접적으로 위협한다(Kim and Kim, 2018). 그러나 고혈압 유병자들은 증상이 거의 나타나지 않으므로 혈압을 측정하기 전까지는 진단되지 않는다. 진득찰 즉 한방에서 희렴은 고혈압을 치료하는 처방 제제로 주로 사용됐기에 이에 착안하여 털진득찰을 이용하여 엔도델린(Endothelin)로 강제 수축 시킨 토끼 기저동맥의 이완 효과를 평가하였다. 본 연구에서는 털진득찰(Sigesbeckia pubescens)의 전초를 이용하여 키레놀 화합물을 분리 후 혈관 이완 효과를 평가하였다. 인체 내 가장 강력한 혈관수축 물질로 알려진 엔도델린은 혈관 평활근 세포막에 존재하는 엔도델린 수용체 아형 A (ET_AR)와 혈관 내피세포막에 존재하는 수용체 아형 B2(ET_B2R)에 작용하여 혈관의 긴장도를 높이고, ET_B1R에 작용하여 긴장도를 낮추는 조절자 임무를 수행한다(Lucchelli et al., 1999). 일반적으로 엔도델린 펩타이드의 경우 염증, 당뇨, 및 심혈관계 질환에서 혈중 농도가 증가하며, 엔도델린 체계의 비정상적 항진은 만성신부전 및 사구체 경화증과 같은 신질환, 특발성 폐섬유화증 및 만성폐쇄성 폐 질환 등의 호흡기계 질환, 대사질환의 중요한 관심거리가 되는 당뇨병성 신경병증 및 망막증, 수족괴사 등의 질환과 전립선 및 대장 등의 암질환 등을 초래한다(Lavoie et al., 1997; Pancrazio et al., 1998). 본 연구에서 엔도델린 유도 뇌 기저동맥의 수축을 억제하는 키레놀의 농도(EC₅₀)를 관찰한 결과 10 ㎍/mL의 농도에서 48% 이상의 유효한 혈관 이완 효능이 관찰되었다. 따라서 키레놀을 이용하여 엔도델린 활성조절 신소재로의 구조적·기능적 도출 연구가 추가로 진행된다면건강 기능성 식품 소재 또는 의약학 소재로의 개발이 가시화될 수 있을 것으로 사료된다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 1999년도 제3회 전자장의 생체영향에 관한 워크숍
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• pp.117-129
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• 1999

Acute effects of locally applied of static magnetic field (SMF) and extremely low frequency electromagnetic field(ELF-EMF) to the cutaneous tissue within a rabbit ear chamber (REC)were evaluated under conscious conditions. Rabbits with the REC were subjected to intravital microscopical investigation by use of microphotoelectric plethysmography(MPPG). There was no dose-response relationship between the extent of vasomotion changes and frequencies(0,20,50, 100Hz)or power levels (1, 5, 10, 25, 50, 100, 200 mT). Under low vascular tone the both fields induce vasodilatation. The effects of SMF (1 mT) on the cutaneous microcirculatory system induced the vasodilatation with enhanced vasomotion under nor-adrenaline-induced high vascular tone as well as the vasoconstriction with reduced vasomotion under acetylcholine-induced low vascular tone. This suggests that the SMF can modulate vascular tone due to the modification of vasomotion biphasically in the cutaneous tissue.

• Archives of Pharmacal Research
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• 제19권6호
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• pp.456-461
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• 1996

Vascular relaxation action of crude extracts of two kinds of Coptidis rhizoma (Coptis chinensis and Coptis japonica, Ranunculaceae) was investigated and compared with that of berberine and palmatine, active alkaloid components of these plants. The results show that total extracts, berberine, and palmatine induced a concentration-dependent vasodilatation of rat thoracic aorta contracted with phenylephrine (PE). Palmatine, unlike to berberine, did not inhibit contraction induced by KCI. In calcium-free media, not only berberine but also crude extracts inhibited calcium-induced contraction. Furthermore, pretreatment of crude extracts inhibited contraction induced by PE noncompetitively. In PE-induced contraction, berberine was 2.5 times more potent than Coptis chinensis in the relaxation of rat aorta in terms of $IC_{50}$ values. Analysis of the effects of crude extracts on the Emax and $IC_{50}(PE)IC_{50}(KCI)$ ratios provides information on selectivity and indicates that extracts exhibit greater inhibition of the contrac tile response induced by PE than by KCI. We concluded that crude extracts have .alpha.-adrenoceptor blocking action and possesses inhibitory effect on calcium influx, which may be at least in part responsible for the antihypertensive action.

• Journal of Chest Surgery
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• 제29권12호
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• pp.1299-1305
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• 1996

고칼륨과 저온이 혈관내피세포의 acetylcholine(Ach)에 의한 혈관이완에 미치는 영향을 알아보기 위하여 흰쥐의 흉부 대동맥을 이용하여 Ach과 sodium nitroprusside(SNP)에 대한 이완 반응을 측정하였다. 실험은 다섯 군으로 나누어서 실시하였으며 각 군을 10례로 하였다. 1군은 대조군으로 어떤 조작도 가하지 않고 organ bath에서 등랑성 긴장도를 측정하였고, 2군(내피세포 제거군)은 내피세포를 물리적으로 제거후 1군과 같은 방법으로 긴장도를 측정하였고, 37$^{\circ}C$ 57에 45분간 처리후 혈관의 등장성 긴장도를 측정하였다. 대조군, 457,4mST및 3757군에서의 Ach에 대한 혈관의 이완은 유의한 차이가 없었으며,내피세포 제거군에서는 Ach에 대한 혈관의 이완이 대조군에 비해 현저하게 감소되었으며, SUP에 대한 혈관의 이완은 모든 군에서 유의한 차이가 없었다. 이에 저자들은 다음과 같은 결론을 내릴 수 있었다. 고농도의 칼륨과 저온자체는 흰쥐의 흉부대동맥 내피세포의 Ach에 대한 이완능을 저해하지 않는다.