• Journal of Chest Surgery
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• v.29 no.12
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• pp.1299-1305
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• 1996

The rat thoracic aorta was harvested to determine whether either hyperkalemla or hypothermia impairs the endothelium-dependent re axation of the vascular smooth muscle. Isolated thoracic aorta segments were studied in five groups(n=10 in each group). In group I(control), the isolated aortic seglnents were suspended in organ bath without any intervention. In group ll(endotheilum removAl). the endothelium of the aortic segment was removed by gentle rubbing of the intimal surface with a pair of forceps. In group III(457), IV(4mST), and V(3757), the aortic segments were exposed for 45minutes to 4$^{\circ}C$ St. Thomas hospital cardioplegic solution(57 : NaCl, 144.3; KCI, 19.6, MgCl:, 15.7 : CaCl, 2.2 mmol/L).4$^{\circ}C$ modified St. Thomas hospital cardioplegic solution(NaCl, 144.3 : KCI. 140.0 : MgCl:, 15.7; CaCl:. 2.2 mmol/L). and 37$^{\circ}C$ 57, before suspending in the organ bath, respectively. Then, aorta segments were suspended in organ baths(physiologic salt solution, 37$^{\circ}C$, 95% oxygen and 5% carbon dioxide) for Isometric tension recording. The vasodilatation to acetylcholine (10-2 to 10-2mol/L) was not impaired in control, 457, 4mST, nd 3757 groups. The vasodilatation to acetylcholine was impaired in endothelium removal group. The vasodilatation to sodium nitroprusslde (10-2 to 10-2 mol/L) was not impaired in all groups. In conclusion, both hyperkalemia and hypothermia do not alter irreversibly the function of the rondothelium of the thoracic aorta of the rat.

• The Korea Journal of Herbology
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• v.28 no.4
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• pp.63-69
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• 2013

Objectives : The purpose of present study was to investigate the vasorelaxant activities and mechanisms of action of the ethanol extract of P. yedoensis leaf (PYL) on isolated rat aortic rings. Methods : Dried P. yedoensis leaves were extracted 3 times with 100% ethanol for 3 h in a reflux apparatus. Isolated rat aortic rings were suspended in organ chambers containing 10 ml Krebs-Henseleit (K-H) solution. The rings were maintained at $37^{\circ}C$ and aerated with a mixture of 95% $O_2$ and 5% $CO_2$. Changes in their tension were recorded via isometric transducers connected to a data acquisition system. Results : PYL relaxed the contraction of aortic rings induced by phenylephrine (PE, 1 ${\mu}M$) or KCl (60 mM) in a concentration dependent manner. However, the vasorelaxant effects of PYL on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings. And the vasorelaxant effects of PYL on endothelium-intact aortic rings were reduced by pre-treatment with $N{\omega}$-Nitro-L-arginine methyl ester (10 ${\mu}M$), methylene blue (10 ${\mu}M$), 1-H-[1,2,4]-oxadiazolo-[4,3-${\alpha}$]-quinoxalin-1-one (10 ${\mu}M$), tetraethylammonium (5 mM). In addition, PYL inhibited the contraction induced by extracellular $Ca^{2+}$ in endothelium-denuded aortic rings pre-contracted by PE or KCl in $Ca^{2+}$-free K-H solution. Conclusions : These results suggest that PYL exerts its vasorelaxant effects via the activation of Nitric Oxide (NO) formation by means of L-arginine and NO-cGMP pathways and via the blockage of receptor operated calcium channels, voltage dependent calcium channels and calcium-activated potassium channels.

• Korean Journal of Medicinal Crop Science
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• v.10 no.2
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• pp.132-138
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• 2002

This study was performed to determine the antimutagenic and cytotoxic effect of ,Kalopanacis cortex endothelium. Methanol extract was used on Salmonella typhimurium TA98, TA100 and three cancer cell lines. In the Ames test, methanol extract of Kalopanacis cortex endothelium alone did not exhibit any mutagenicity but showed substantial inhibitory effects against mutation induced by 4-nitroquinoline-l-oxide(4NQO), N'-methyl- N'-nitro-N-nitrosoguanidine(MNNG) and benzo(a)pyrene(B(a)P). The methanol extract of Kalopanacis cortex endothelium showed approximately 79.29% and 75.38% inhibitory effect on the mutagenesis induced by 4NQO and B(a)P, respectively, against TA98 strain. Whereas 79.49%, 89.3% and 68.85% inhibitions were observed on the mutagenesis induced by 4NQO, MNNG and B(a)P against TA100 strain. Methanol extracts from Kalopanacis cortex endothelium showed high antimutagenic effects against 4NQO, MNNG and B(a)P. The anticancer effects of methanol extract from Kalopanacis cortex endothelium against human lung carcinoma(A549), human breast adenocarcinoma (MCF-7) and human hepatocellular carcinoma(Hep3B) were investigated. The treatment of 0.5mg/ml Kalopanacis cortex endothelium methanol extracts had the highest cytotoxicity against A549(81.54%), followed by MCF-7(81.92%) and Hep3B (78.57%). In contrast 0.5mg/ml treatment of methanol extracts from Kalopanacis cortex endothelium had only $4{\sim}25%$ cytotoxicity on normal human liver cell(293).

• Journal of Ginseng Research
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• v.16 no.1
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• pp.78-78
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• 1992

• YAKHAK HOEJI
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• v.50 no.3
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• pp.208-213
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• 2006

Rat aortic ring preparations were mounted in organ baths, exposed to sodium cyanide $(0.01{\sim}1.0\;mM)$ for 10 min, and then subjected to contractile agents or relaxants such as acetylcholine, sodium nitroprusside and isoproterenol. Presence of low concentration of sodium cyanide did not affect the contractile response to KCl or phenylephrine in the aortic rings with intact endothelium or endothelium denuded. Sodium nitroprusside but not acetylcholine or isoproterenol augmented phenylephrine-induced intact or denuded vascular contraction in the presence of low concentration of sodium cyanide. In conclusion, this study provides the evidence concerning the potentiating effect of sodium nitroprusside on the contraction induced by phenylephrine in rat aortic rings regardless of endothelial function.

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.226-230
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• 1999

We have isolated a sesquiterpene lactone, cumambrin A from the dried flowers of Chrysanthemum boreale Makino and reported its chemical structure. The aim of the present study was to investigate whether the exogenous administration of cumambrin A has a pharmacological effect on normalization of blood pressure in the spontaneously hypertensive rats (SHR). In vitro studies: Relaxative response induced by cumainbrin A was increased with dose-dependent manner and showed maximizing response at a concentration of $5{\times}10^{-4}M$. Further, this relaxative response was significantly increased at a condition of endothelium present than that of endothelium denuded. In vivo studies: The normalizing effect of cumambrin A on blood pressure was also increased with time-dependent manner and then gradually recovered to normal condition at approximately 4 hrs after cumambrin A treatment.

• Journal of Nutrition and Health
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• v.30 no.3
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• pp.244-251
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• 1997

The effects of Artemisia princeps var orientalis(mugwort), Circium japonicum var ussuriense (Unggungqui) on cadiovascular system in hyperlipidemic rats were investgated. Thirty rats devided into 5 experimental groups, were fed with the diet contained 1% chlesterol, 0.25% sodium cholate, 10% coconut oil and 5% lard by the same method of previous paper1). Contractile and relaxation responses in the isolated artria and thoracic aortae were measured and the morphological changes of the aortic endotherium from the rats were inspected. The responses of the right atrial to isoproterenol were significantly lower value in Ungungqui powder diet group(UP) and mugwort powder diet group(MP) than the control. The contraction force by injectin of phenylephrine and calcium in isolated thoracic aortae was significantly low value in the UP and the MP groups compaired to the control. The relaxation rate by acetylcholine in isolated thoracic aortae represented significantly higher value in UP than control. The morphological changes of endothelial cell suface was smallest in UP and the damage of endothelium by retarded in MP. Although Ungungqui and mugwort extract diet groups(UE, ME) were advanced, those were less than control.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2008.10a
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• pp.174-174
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• 2008

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.98-98
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• 2001

It has been suggested that hyperuricemia is related to the development of essential hypertension. Hypertensive patients with hyperuricemia has decreased glomerular filtration activity as compared to normotensive patients with hyperuricemia. These studies indicates uric acid concentrations in blood is associated with hypertension, Probenecid is an uricosuric agent which decreases uric acid reabsorption at the proximal tubule. Recently, we have shown that probenecid exerts anti-hypertensive action in Spontaneously Hypertensive Rats. Considering these results, I have designed a series of experiments to explore potential mechanism of antihypertensive action, of probenecid. In isolated rat thoracic aorta. probenecid significantly prevented phenylephrine-induced contraction of the blood vessel. When endothelium removed blood vessels were used, probenecid produced same effect as the intact blood vessels, indicating that probenecid directly act through the ${\alpha}$ -adrenergic receptor in vascular smooth muscles rather than through endothelium. These results suggest that one of the mechanism of antihypertensive effects of probenecid is due to the direct inhibition of ${\alpha}$ -adrenergic receptor in blood vessels.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.297-307
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• 2002

We have isolated a sesquiterpene lactone, cumambrin A from the dried flowers of Chrysanthemum boreale Makino and reported its chemical structure. The aim of the present study was to investigate whether the exogenous administration of cumambrin A has a pharmacological effect on normalization of blood pressure in the spontaneously hypertensive rats (SHR). In vitro studies: Relaxative response induced by cumambrin A was increased with dose-dependent manner and showed maximizing response at a concentration of 5?0-4 M. Further, this relaxative response was significantly increased at a condition of endothelium present than that of endothelium denuded. in vivo studies: The normalizing effect of cumambrin A on blood pressure was also increased with time-dependent manner and then gradually recovered to normal condition at approximately 4 hrs after cumambrin A treatment.