• 동의생리병리학회지
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• 제29권6호
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• pp.492-497
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• 2015

In the present study, vasorelaxant effect of the extract of seeds of Oenothera odorata (SOO) and its possible mechanism responsible for this effect were examined in vascular tissues isolated from rats. Changes in vascular tension, 3',5'-cyclic monophosphate (cGMP) levels were measured in thoracic aorta rings from rats. Methanol extract of seeds of Oenothera odorata relaxed endothelium-intact thoracic aorta in a dose-dependent manner. A dose-dependent vascular relaxation was also revealed by treatment of ethylacetate, n-butanol, and H₂O (aqua extract of seeds of Oenothera odorata , ASOO) extracts partitioned from methanol, but not by hexane extract. However, the vascular relaxation induced by ASOO were abolished by removal of endothelium of aortic tissues. Pretreatment of the endothelium-intact vascular tissues with N^G-nitro-L-arginine methyl ester (L-NAME) or ¹H-[1,2,4]-oxadiazole-[4,3-α]-quinoxalin-1- one (ODQ) significantly inhibited vascular relaxation induced by ASOO. Moreover, incubation of endothelium-intact aortic rings with ASOO increased the production of cGMP. However, ASOO-induced increases in cGMP production were blocked by pretreatment with L-NAME or ODQ. The vasorelaxant effect of ASOO was attenuated by tetraethylammonium (TEA), 4-aminopyridine, and glibenclamide attenuated. On the other hand, the ASOO-induced vasorelaxation was not blocked by verapamil, and diltiazem. Taken together, the present study demonstrates that ASOO dilate vascular smooth muscle via endothelium-dependent NO-cGMP signaling pathway, which may be closely related with the function of K⁺ channels.

• The Korean Journal of Physiology and Pharmacology
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• 제20권5호
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• pp.547-556
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• 2016

Myometrial relaxation of mouse via expression of two-pore domain acid sensitive (TASK) channels was studied. In our previous report, we suggested that two-pore domain acid-sensing $K^+$ channels (TASK-2) might be one of the candidates for the regulation of uterine circular smooth muscles in mice. In this study, we tried to show the mechanisms of relaxation via TASK-2 channels in marine myometrium. Isometric contraction measurements and patch clamp technique were used to verify TASK conductance in murine myometrium. Western blot and immunehistochemical study under confocal microscopy were used to investigate molecular identity of TASK channel. In this study, we showed that TEA and 4-AP insensitive non-inactivating outward $K^+$ current (NIOK) may be responsible for the quiescence of murine pregnant longitudinal myometrium. The characteristics of NIOK coincided with two-pore domain acid-sensing $K^+$ channels (TASK-2). NIOK in the presence of $K^+$ channel blockers was inhibited further by TASK inhibitors such as quinidine, bupivacaine, lidocaine, and extracellular acidosis. Furthermore, oxytocin and estrogen inhibited NIOK in pregnant myometrium. When compared to non-pregnant myometrium, pregnant myometrium showed stronger inhibition of NIOK by quinidine and increased immunohistochemical expression of TASK-2. Finally, TASK-2 inhibitors induced strong myometrial contraction even in the presence of L-methionine, a known inhibitor of stretch-activated channels in the longitudinal myometrium of mouse. Activation of TASK-2 channels seems to play an essential role for relaxing uterus during pregnancy and it might be one of the alternatives for preventing preterm delivery.

• 대한약리학회지
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• 제29권2호
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• pp.263-274
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• 1993

$K^+$통로는 기도 평활근 세포에 존재하며 이들 통로가 활성화되면 평활근의 과분극의 결과 이완작용이 나타난다. $K^+$통로의 이런 효과는 과민반응과 천식 치료에 응용될 수 있으므로 우리는 $K^+$통로 개방제인 cromakalim (BRL34915, CK)이 $IgG_1$ 항체로 감작시킨 기도 및 폐조직으로 부터 유리되는 매개체 유리에 미치는 영향을 조사하였다. 피동적으로 감작된 두 조직은 $2{\times}10^{-6}\;M$의 CK로 30분동안 superfusion시킨 후 CK와 항원 (Ox-HSA) 0.1 mg/ml로 자극하였다. 또한 비만세포를 이용하여 CK의 효과를 조사하였다. 해명 폐조직 비만세포는 효소에 의한 digestion method (monodispersed; 미분리 정제), count current elutriation에 의한 방법(partially purified; 부분분리정제), 그리고 discontinuous Percoll방법(highly purified; 순수분리정제)에 의해 순수 분리되었다. CK로 전처치한후, 피동적으로 감작된 비만세포는 OA와 CaI의 여러 농도에 의해 자극되었다. 유리된 Hist은 spectrophotofluorometry에 의해, LT는 면역방사법에 의해 측정되었다. CK 전처치는 $IgG_1$ 감작후 항원에 의해 자극된 기도 조직에서 Hist 유리량을 35%까지, LT 유리량은 40%까지 감소시켰으나 기도 평활근 수축력에는 반응을 나타내지 못하였다. 항원 유도 폐조직에 있어서 CK전처치는 Hist유리량을 25%까지 감소시켰으나 LT 유리에는 미약한 감소를 나타내었다. 해명의 미분리정제, 부분분리정제, 그리고 순수 분리 정제된 비만세포로부터 Hist과 LT은 면역자극(OA)이나 비면역자극(CaI)에 의해 농도 의존적으로 유리되었다. 비만세포에서 유리된 LT는 5-lipoxygenase억제제인 A64077에 의해서 억제됨이 확인되었다. CK전처치는 OA유도 및 CaI유도 해명 폐조직 비만세포에서 Hist과 LT 유리량을 20%까지 감소시켰다. $IgG_1$ 감작후 Ox-HSA유도 기도 평활근 조직이나 혹은 OA유도 및 CaI유도 비만세포에서 Hist과 LT유리에 미치는 CK의 억제효과는 TEA와 GBC에 의해 완전히 봉쇄되었다. 이상의 결과에서 폐조직 비만세포는 LT를 유리할 수 있는 세포로 간주되며, 기도 평활근 이완제로 알려져 있는 CK은 특수 항원 유도 기도 평활근조직에서 매개체 유리를 부분적으로 억제하며, CK은 또한 OA유도 및 CaI로 유도된 순수분리 정제된 비만세포에서 매개체 유리를 부분적으로 억제하는 것으로 보아 비만세포가 활성화시 야기되는 여러 생화학적 현상중에서 미약하나마 $K{^+}$통로가 관여할 것으로 사료된다.

• The Korean Journal of Physiology
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• 제16권1호
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• pp.1-11
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• 1982

Force development of smooth muscle cells is directly regulated by the concentration of free calcium ions in the sarcoplasm, and the sarcoplasmic concentration of calcium ion can be modulated by electrogenic Na-K pump. The role of Na-K pump on vascular tone was studied in isolated rabbit renal artery. Helical strips of arterial muscle were prepared from left renal arteries. All experiments were performed in $HCO_3^--buffered$ Tyrode solution which was aerated with $3%CO_2-97%\;O_2$ mixed gas and kept at $35^{\circ}C$. In some experiments, rabbit was injected intraperitoneally $18{\sim}24$ hours prior to the experiments, with a large dose(5 mg/kg body wt) of reserpine, in order to eliminate the catecholamines present in intrinsic adrenergic nerve terminate. Treatment used in this experiment that inhibits Na-K pump was the exposure of strips to K-free Tyrode solution. Contractile response to K free Tyrode solution developed slowly and the time required for maximum contracture was $20{\sim}30$ minutes. This K-free contracture was rapidly relaxed by the addition of potassium to the bathing solution. No K-free contracture occurred in a Ca-free Tyrode solution. But contraction developed rapidly when calcium ion was added to the bathing solution after 30 minute exposure of the strip to Ca-free Tyrode solution. This contracture was completely inhibited by Ca-antagonist, verapamil. The K-free contracture was abolished by ${\alpha}-adrenergic$ blocker, phentolamine, as well as by the catecholamine depletion from adrenergic nerve terminals. Even in reserpinized strip, the exogenous norepinephrine-induced contraction in K-free Tyrode solution was rapidly suppressed by the addition of potassium ion. The results of this experiment suggest that K free contracture develops by norepinephrine release from adrenergic nerve terminals, while the relaxation of K-free contracture is induced by the activation of electrogenic Na-K pump.

• Journal of Chest Surgery
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• 제37권3호
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• pp.210-219
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• 2004

외부 자극에 의하여 세포 내 $Ca^2$$^{+}$이 증가하면 세포 내 $K^{+}$이 유출되어 세포 외 $K^{+}$ 농도는 수 mM 범위에서 증가할 수 있다. 이러한 세포 외 $K^{+}$의 증가가 혈관 수축성에 미치는 영향을 규명하고자, 세포 외 $K^{+}$가 혈관평활근 수축성, 내피세포 의존성 이완과 혈관내피세포 $Ca^2$$^{+}$ 농도에 미치는 영향을 알아보고자 하였다. 토끼에서 분리한 경동맥, 상장간막동맥 분지, 기저동맥과 쥐의 대동맥에서 등장성 수축을 기록하였으며 배양한 쥐의 대동맥 혈관내피세포와 인간 제대정맥 내피세포에서 세포 내 $Ca^2$$^{+}$ 변화를 측정하였다. 세포 외 $K^{+}$ 농도를 6에서 12 mM로 증가하는 경우 도관동맥인 토끼 경동맥은 수축성에 변화가 없는 반면 저항혈관인 기저동맥과 상장간막동맥분지는 이완하였다. 이러한 $K^{+}$ 유발 이완은 혈관 종류에 따라 차이가 있었는데 기저동맥에서는 세포 외 $K^{+}$ 농도를 6에서 12 mM로 증가하였을 때보다 세포 외 $K^{+}$ 농도를 1에서 3 mM로 증가하였을 때 더 크게 이완하였으며 상장간막동맥의 분지에서는 반대로 세포 외 $K^{+}$ 농도를 6에서 12 mM로 증가하였을 때 더 크게 이완하였다. 그리고 세포 외 $K^{+}$ 농도를 6에서 12 mM로 증가하였을 때의 이완은 $Ba^2$$^{+}$에 의하여 억제되는 반면 1에서 3 mM로 증가에 의한 이완은 억제되지 않았다. 쥐 대동맥에서도 토끼 경동맥과 동일한 효과가 관찰되었는데 세포 외 $K^{+}$ 농도를 6 mM에서 12 mM로 변화시켜도 norepinephrine혹은 prostaglandin $F_2$$_{\alpha}$에 의한 수축력은 유의한 변화가 없었다. 또한 세포 외 $K^{+}$ 농도를 점차 증가시키는 경우 12 mM 이상 증가가 되면 혈관평활근이 수축하기 시작하였지만 12 mM 이하의 증가에 의해서는 혈관평활근의 수축력은 증가하지 않았다. 한편 쥐 대동맥에서 acetylcholine에 의하여 유발된 내피세포 의존성 이완은 세포 외 $K^{+}$ 농도를 정상 6 mM에서 12 mM로 증가시키면 억제되었다. 한편 배양한 쥐 대동맥 내피세포에서는 acetylcholine 혹은 ATP에 의하여 세포 내 $Ca^2$$^{+}$이 증가하였다. 증가한 세포 내 $Ca^2$$^{+}$은 세포 외 $K^{+}$농도를 6 mM에서 12 mM로 증가시키면 가역적 및 농도 의존적으로 감소하였다. 세포 외 $K^{+}$ 증가에 의한 세포 내 $Ca^2$$^{+}$ 억제 효과는 인간 제대정맥 내피세포에서도 관찰되었다. 그리고 세포 외 $K^{+}$ 증가에 의한 내피세포 의존성 이완의 억제효과는 $Na^{+}$- $K^{+}$ pump 억제제인 ouabain과 $Na^{+}$-C $a^2$$^{+}$exchanger 억제제인 N $i^2$$^{+}$에 의하여 억제되었다. 이러한 실험 결과로 미루어 세포 외 $K^+$의 증가는 저항혈관 평활근을 이완시키는데 그 기전은 혈관 종류에 따라 차이가 있었다. 그리고 세포 외 $K^{+}$의 증가는 혈관내피세포 $Ca^2$$^{+}$을 감소시켜 내피세포 의존성 이완을 억제하는데 이는 $Na^2$$^{+}$- $K^2$$^{+}$pump를 활성화시켜 일어나는 것으로 생각된다.

• 생명과학회지
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• 제24권5호
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• pp.491-497
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• 2014

아무르불가사리(Asterias amurensis)의 6가지의 조직 추출물들을 사용하여 항균활성, 항산화 활성 및 평활근에 대한 수축과 이완반응에 대한 활성을 측정하였다. 1% (v/v) 초산용액을 사용하여 동결 건조한 샘플들을 추출하여 각각의 활성측정에 사용한 결과, 껍질을 제외한 모든 조직 추출물들은 E. coli D31에 대해 강한 항균활성을 나타내었고, 근육 및 장관 추출물들은 별불가사리(Asterina pectinifera)의 DRM에 대해 수축반응을 나타냈다. 한편, 오징어(Todarodes pacificus) 식도에 대한 수축반응은 실험에 사용한 모든 조직 추출물들에서 검출되었다. 특히, 간 추출물의 수축활성은 다른 조직의 추출물의 활성에 비해 더 높았다. 뿐만 아니라 간, 근육 및 소화관 추출물은 졸복(Takifugu pardalis)의 장관에 대해서 수축반응을 나타냈다. 별불가사리의 DRM에 대한 이완반응은 실험에 사용한 모든 조직 추출물들에서 활성을 나타냈다. 항산화 활성은 장관, 간 및 껍질의 추출물들에서 강하게 나타났다. 따라서 아무르불가사리는 새로운 생체기능 조절물질의 발견에 대한 가능성을 지닌 자원이라는 것을 본 연구의 결과들은 제시한다.

• The Korean Journal of Physiology and Pharmacology
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• 제3권1호
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• pp.1-10
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• 1999

We sought to find out the mechanism of vascular relaxation by extracellular $K^+$ concentration $([K^+]_o)$ in the cerebral resistant arteriole from rabbit. Single cells were isolated from the cerebral resistant arteriole, and using voltage-clamp technique barium-sensitive $K^+$ currents were recorded, and their characteristics were observed. Afterwards, the changes in membrane potential and currents through the membrane caused by the change in $[K^+]_o$ was observed. In the smooth muscle cells of cerebral resistant arteriole, ion currents that are blocked by barium, 4-aminopyridine (4-AP), and tetraethylammonium (TEA) exist. Currents that were blocked by barium showed inward rectification. When the $[K^+]_o$ were 6, 20, 60, and 140 mM, the reversal potentials were $-82.7{\pm}1.0,\;-49.5{\pm}1.86,\;-26{\pm}1.14,\;-5.18{\pm}1.17$ mV, respectively, and these values were almost identical to the calculated $K^+$ equilibrium potential. The inhibition of barium-sensitive inward currents by barium depended on the membrane potential. At the membrane potentials of -140, -100, and -60 mV, $K_d$ values were 0.44, 1.19, and 4.82 ${\mu}M,$ respectively. When $[K^+]_o$ was elevatedfrom 6 mM to 15 mM, membrane potential hyperpolarized to -50 mV from -40 mV. Hyperpolarization by $K^+$ was inhibited by barium but not by ouabain. When the membrane potential was held at resting membrane potential and the $[K^+]_o$ was elevated from 6 mM to 15 mM, outward currents increased; when elevated to 25 mM, inward currents increased. Fixing the membrane potential at resting membrane potential and comparing the barium-sensitive outward currents at $[K^+]_o$ of 6 and 15 mM showed that the barium- sensitive outward current increased at 15 mM $K^+.$ From the above results the following were concluded. Barium-sensitive $K^+$?channel activity increased when $[K^+]_o$ is elevated and this leads to an increase in $K^+-outward$ current. Consequently, the membrane potential hyperpolarizes, leading to the relaxation of resistant arteries, and this is thought to contribute to an increase in the local blood flow of brain.

• The Korean Journal of Physiology
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• 제28권2호
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• pp.169-179
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• 1994

The effect of extracellular and intracellular pH on vascular tone and $^{45}Ca$ uptake were investigated in aortic strips and dispersed single aortic smooth muscle cells of spontaneously hypertensive rats (SHR) and aged-matched Wistar-Kyoto rats (WKY). The contraction produced by a change of extracellular pH (pHo) in the range of $6.5{\sim}8.3$ was estimated by comparison with the level of vascular tone at pH 7.4. Contraction was induced below pHo 6.5 in WKY, pHo 7.1 in SHR, and over pHo 8.0 on both strains. The amplitude of contraction induced by high pHo (over pHo 7.7) was similar in SHR and WKY, but that induced by low pHo (below pHo 7.1) in SHR was greater than that in WKY. Either high pHo- or low pHo-induced contractions in WKY and SHR were not induced in the Ca-free Tyrode's solution and were induced by the addition of Ca. $^{45}Ca$ uptake increased progressively as pHo was increased from 6.8 to 8.1 in the single aortic smooth muscle cells of WKY and SHR. $NH_4Cl$ induced a gradually developing contraction in a dose-dependent manner $(5\;mM{\sim}30\;mM)$ and the removal of $NH_4Cl$ induced transient contraction was followed by profound relaxation in the aortic rings of both strains. The contractions induced by $NH_4Cl$ or by the removal of $NH_4Cl$ in SHR were significantly greater than that in WKY. These contractions were not induced in Ca-free Tyrode's solution. $^{45}Ca$ uptake was increased by $NH_4Cl$ (20 mM) and was not changed by the removal of $NH_4Cl$ (20 mM) in the aortic strips of WKY and SHR. As a summary of above results, the vascular tone of SHR was more sensitive to the change pHi and pHo than that of WKY. The contractions induced by change of extracellular or intracellular pH depended on extracellular Ca in the aorta of SHR nnd WKY. However, the Ca uptake was in accord with the changes of contraction but increase in contraction by low pH was not accompanied by an increase in Ca uptake in both strains.

• 대한한방내과학회지
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• 제24권2호
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• pp.220-232
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• 2003

Objective : The purpose of this study was to analyze the effects of HwangRyunHaeDok-Tang and combinations of constituent herbs on the arterial contraction. Methods : In order to investigate the effects Scutellariae Radix. Coptidis Rhizoma, Phellodendri Cortex and Gardeniae Fructus, in which one of them, two of them, and all of them, were used to exam. Results : The results were summarized as follows; 1. HwangRyunHaeDok-Tang significantly inhibited the contraction of artery induced by Norepinephrine(NE). However the atonic effect was slightly blunted when the vascular endothelial cell was removed. No significant change in the atonic effect of HwangRyunHaeDok-Tang was found when $_L-NNA$ was used as a preliminary treatment. These results indicate that the vascular atonic effect by HwangRyunHaeDok-Tang is slightly dependent on the endothelial cell, and that the HwangRyunHaeDok-Tang works directly to the vascular smooth muscle in creating the vascular atonic effect. 2. The pretreatment of HwangRyunHaeDok-Tang extract significantly inhibited the contractile response to additive application of $Ca^{2+}$ in the strips which were contracted by NE in $Ca^{2+}$-free solution. 3. HwangRyunHaeDok-Tang extract increased the contraction of arterial smooth muscle induced by KCl. Therefore, it can be concluded that HwangRyunHaeDok-Tang may block the NE-receptor or receptor-operated $Ca^{2+}$ channel. 4. It was determined that Scutellariae Radix, Coptidis Rhizoma and Phellodendri Cortex among the ingredients of HwangRyunHaeDok-Tang have a vascular atonic effect. In addition, those ingredients plays a role in strengthening the atonic effect by working with other herbal medicines. Gardeniae Fructus causes the blood vessel to contract. but it does not influence the atonic effects of other herbal medicines. However Gardeniae Fructus tends to inhibit the vascular atonic effect of Phellodendri Cortex. Conclusion : Based on the above results, it can be said that HwangRyunHaeDok-Tang can be applied to cure hypertension considering those three herbs have significant effects of relaxation.

• 한국임상수의학회지
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• 제6권2호
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• pp.227-259
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• 1989

Waterpepper is a weed which grows on damp soil. especially near swamps, and in shallow water of ponds and ditches. It Is widespread throughout the country In abundant colonies. In the present experiments, possible toxic effects of waterpepper were investigated in ruminants. Pour cows were fed waterpepper ad libitum or by force in the from of green forage, hay and/or powder, 8 goats were administered in the form of methanol extract, and 4 goats, crude juice, into the lumen. Clinical signs were examined as well as urinalysis, hematology, serum chemical analysis, pH/blood gas analysis and chclinesterase activities following administration of waterpepper. Six goats which were administered the methanol extract or crude juice were sacrificed for pathological examinations., In addition to the clini copathological examinations, the chemical constituents of waterpepper were qualitively analyzed from the methanol extract and the Effects of the waterpepper crude juice were examined on the motility of rabbit duodenum and uterus. It is revealed that waterpepper contains steroids, terpenoids, flavonoids, tannin and essential oils in the methanol extract and nitrates in the crude juice. The crude juice of waterpepper relaxed the rabbit uterine and duodenal smooth muscles. The constraction of duodenum by acetylcholine or BaCl$_2$ were partially inhibited by pretreatment of the crude juice. However, the relaxation of duodenum by the crude juice was not blocked by the pretreatments of phenoxybenzamlne, propranolol, cocaine, reserpine and tetrodotoxin. The constituents of waterpepper to evoke elaxation of duodenal smooth muscle were stable to heat. The cows administered waterpepper showed common clinical symptoms such as acrid expression, restlessness, dullness, inappetence, anorexia, severe diarrhea, mild bloat and left displacement of abomasum, while bloody feces was shown in a cow. The goats administered the mothanol extract showed common clinical signs such as acrid expression, restlessness, dullness, inappetence and soft feces, while bloody feces was shown in a goat, A goat adminstered the crude juice showde bloody feces and diarrhea. Respiratory rates and heart beats were increased along with diarrhea in the experimental cows. The erythrocyte counts and MCHC were decreased whereas PCV, MCV and neutrophils were increased in the cows administered waterpepper. In goats administered methanol extract, there were decreases in erythrocytes, PCV and hemoglobin content, and an increase in MCHC. The goats ingester with the crude juice showed negligible changes in hematologic values compared with control group which was administered the same amount of water instead of the crude juice. The contents of serum calcium, Inorganic phosphorus, magnesium, Iron, glucose, cholesterol, total protein, triglycerides and phospholipids were tended to decrease in cows. In goats serum iron, glucose, triglycerides, cholesterol, BUN and phospholipids content were decreased while the content of sodium and chloride were increased after administration of the methamol extract The goats ingested with the crude juice did not show significant changes in serum chemical analysis. Even though there were some pathological findings such as hyperemia in the small intestines and kidneys and swelling of liver parenchymal cells, the values of serum AST, ALT, LDH, alkaline phosphatase, total bilirubin and creatinine did not change significantly. While proteins, hemoglobin and blood were detected in the urine of cows, urine pH, ketone bodies, glucose, bilirubin and urobilinogen content were normal or undetected. There were no significant changes in pH/bolld gas analysis data of cows and cholinesterase activities of plasma and erythrocytes of cows and goats ingested with waterpepper or the methanol extract. It is concluded that waterpepper irritates the gatrointestinal system, causes abdominal pain, relaxes the gastrointestinal smooth muscle and dilatates blood vessels supplied to the system. The irritation and relaxation may lead to abnormal fermentation, maldigestion and malabsorption of nutrients and result in diarrhea, body feces, mild bloat and left displacement of abomasum.