• Title/Summary/Keyword: Aorta ring

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A Study of Mechanism Involved in Cadmium-induced Platelet Aggregation

  • Song Cheul-Soo;Hong Ki-Whan
    • The Korean Journal of Pharmacology
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    • v.20 no.1 s.34
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    • pp.41-46
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    • 1984
  • Cadmium (Cd) was administered by a series of weekly intraperitoneal injections at dose of 2mg/kg in rabbits and rats. The levels of malondialdehyde (MDA) and thromboxane $B^2(TXB_2)$ in platelet-rich plasma from Cd-poisoned animals were significantly higher than those of the control group. Furthermore, the inhibition of 6-keto-prostaglandin $F_{1{\alpha}}$, production in Cd-treated aorta ring was inversely related to the enhancement of platelet aggregation. These results suggest that Cd not only inhibits prostacyclin synthesis in the arterial endothelium, but also stimulates the platelet aggregation by enhancing thromboxane AZ production. These findings are assumed to support the evidence of an effect of Cd toxicity on the vascular wall and platelet function in raising arteriall pressure.

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Modified Bentall Operation and the Double Sewing Ring Technique -2 case reports- (변형식 벤탈수술; 이중봉합링 수술법 - 2예 치험 -)

  • Kim, Tae-Yun;Lee, Jung-Moon;Choi, Jong-Bum;Kim, Min-Ho;Jo, Jung-Ku
    • Journal of Chest Surgery
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    • v.43 no.2
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    • pp.156-160
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    • 2010
  • The Bentall-DeBono operation is the technique of choice for aortic root replacement. When the patients have contraindications for lifelong anticoagulation, the biologic Bentall operation may be a good option. However, complex reoperation may be required when bioprosthetic degeneration occurs. For this reason, a new technique for simple reoperation after the Bentall operation has recently been performed by some surgeons. We performed a similar technique in two patients with aortic root dilation and for whom aortic valve sparing techniques could not be performed because of an unrepairable valve contour, we think this modification seems to be simple and reproducible for reoperation.

Ketamine-Induced Blood Pressure Lowering in the Rat (흰쥐에서 Ketamine에 의한 혈압하강)

  • Yu Xian-Feng;Kim Shang-Jin;Lee Mun-Young;Kang Hyung-Sub;Kim Jin-Shang
    • Journal of Veterinary Clinics
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    • v.22 no.3
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    • pp.220-227
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    • 2005
  • Although ketamine has been used in the field of anesthetic medicine for its safety and favourable respiratory effects, the cardiovascular effects of ketamine is still controversial. To clarify the action and mechanism of ketamine upon cardiovascular system, arterial blood pressure, tension of aortic ring, left ventricular developed pressure and heart rate were measured in rats, Ketamine produced two types of effects on arterial blood pressure in anesthetized rats; monophasic effect (blood pressure lowering) and biphasic effect (initial transient blood pressure increasing following sustained lowering), The ketamine-induced lowering of aterial blood pressure showed a concentration-dependent manner, inhibited by the pretreament of $MgCl_2$ and potentiated by the pretreatment of $CaCl_2$. The ketamine-induced lowering of aterial blood pressure was suppressed by the pretreatment of nifedipine, verapamil or lidocaine. In phenylephrine-precontracted endothelium intact (+E) aortic rings, ketamine sometimes caused a small enhancement of contraction ($112.5{\pm}3.6{\%}$). However, in many experiments, ketamine produced a concentration-dependent relaxation in +E aortic rings precontracted with either phenylephrine or KCl. Ketamine-induced relaxation was significantly greater in KCl-precontracted strips than phenylephrine-precontracted strips. In phenylephrine-precontracted +E aortic rings, the ketamine-induced vasorelaxation was not suppressed by endothelium removal or by the pretreatment of a nitric oxide synthase inhibitors, L-$N^G$-nitro-arginine and a guanylate cyclase inhibitors, methylene blue, suggesting that the ketamine-induced vasorelaxation is not dependent on the endothelial function. In addition, ketamine elicited an increase in left ventricular developed pressure in perfused hearts accompanied by decrease in heart rate. These results suggest that ketamine could evoke a hypotension due to vasorelaxation and decrease in heart rate in rats. The inhibitory effect of cardiovascular system might be associated with modulation of $Ca^{2+}$ homeostasis.

Glucosamine increases vascular contraction through activation of RhoA/Rho kinase pathway in isolated rat aorta

  • Kim, Do-Hyung;Seok, Young-Mi;Kim, In-Kyeom;Lee, In-Kyu;Jeong, Seong-Yun;Jeoung, Nam-Ho
    • BMB Reports
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    • v.44 no.6
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    • pp.415-420
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    • 2011
  • Diabetes is a well-known independent risk factor for vascular disease. However, its underlying mechanism remains unclear. It has been reported that increased influx of the hexosamine biosynthesis pathway (HBP) induces O-GlcNAcylation of proteins, leading to insulin resistance. In this study, we determined whether or not O-GlcNAc modification of proteins could increase vessel contraction. Using an endothelium-denuded aortic ring, we observed that glucosamine induced OGlcNAcylation of proteins and augmented vessel contraction stimulated by U46619, a thromboxane $A_2$ agonist, via augmentation of the phosphorylation of MLC20$MLC_{20}$, MYPT1(Thr855), and CPI17, but not phenylephrine. Pretreatment with OGT inhibitor significantly ameliorated glucosamine-induced vessel constriction. Glucosamine treatment also increased RhoA activity, which was also attenuated by OGT inhibitor. In conclusion, glucosamine, a product of glucose influx via the HBP in a diabetic state, increases vascular contraction, at least in part, through activation of the RhoA/Rho kinase pathway, which may be due to O-GlcNAcylation.

Surgical Experiences of Shone's Syndrome (숀 증후군의 외과적 치료)

  • Won, Tae-Hui;Lee, Jeong-Ryeol;Kim, Yong-Jin;No, Jun-Ryang
    • Journal of Chest Surgery
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    • v.30 no.9
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    • pp.862-868
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    • 1997
  • Shone's syndrome is a congenital cardiac malformation that consists of multiple levels of left heart obstruction including supravalvular mitral ring, congenital mitral stenosis(parachute mitral valve), subaortic stenosis, and coarctation of aorta. This syndrome is a very rare congenital anomaly and its prognosis is poor. We experienced 9 patients with Shone's syndrome between 1985 and 1994. There were 8 male and 1 female patients, and mean age was 33.0$\pm$31.0 months ranged from 2 months to 1 1 years. The congenital mitral, stenosis and coarctation of aorta existed in all patients and the supravalvular mitral ring and subaortic stenosis in 4 patients. Two patients had all four anatomic lesions. 3 patients underwent one stage total correction and the other 6 patients underwent two staged operation that was initial coarctoplasty with thoracotomy and later correction of intracardiac anomalies with median sternotomy. A third operation was performed in 2 patients. These procedures included reoperation for coarctation and replacement of mitral valve for persistent mitral stenosis. There was no operative death at the first operation but two operative deaths at the second operation. The cause of death in two cases was severe heart failure secondary to left ventricular hypoplasia. There was no operative death at the third operation. The seven survivors have beeli followed from 11 months to 12 years(mean follow-up 6.7 $\pm$ 3.6 years). There was no late death and the New York HeArt Association activity level was class I for all patients. We conclude that a food lone-term outcome can be expected by proper surgical treatment tailred to each individual's anatomy and pathophysiology although the operative mortality and morbidity of Shone's syndrome are high.

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Contractile Response of Methylene Blue on Vascular Smooth Muscles - Rabbit Thoracic Aorta and Porcine Mesenteric Artery - (혈관평활근에 대한 Methylene Blue의 수축작용 - 가토흉부대동맥근과 돼지장간막동맥근 -)

  • Baik, Yung-Hong;Choi, Soo-Yong;Kim, Jae-Ha;Cho, Nam-Kee
    • The Korean Journal of Pharmacology
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    • v.26 no.1
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    • pp.13-23
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    • 1990
  • Methylene Blue (MeB) and gentian violet $(10^{-6}{\sim}10^{-4}\;M)$ produced contractions in isolated thoracic aortic preparations of rabbits in a dose-dependent fashion, while other dyes, evans blue and eosine yellowish, did not affect the basal tension in the same range of doses. Porcine mesenteric arterial rings also responded to MeB with dose-dependent contractions. Single dose of $10^{-4}$ M MeB produced a biphasic response: contraction followed by relaxation. The contraction developed slowly within $2{\sim}4$ min and peaked in about 20 minutes and then slowly relaxed to the basal level. Tyramine $(10^{-4}\;M)$ also induced contraction but it developed faster and was more persistent than that of MeB. While the tyramine-induced tension was reproducible, the MeB-induced one wat not reiterable until 3 to 5 hours after washing out the MeB. Adding $10^{-4}$ M MeB further potentiated the contraction induced by $10^{-4}$ M tyramine. However, the MeB contraction was not affected by further addition or tyramine. Both tyramine- and MeB-induced tensions were abolished or significantly inhibited by pretreatment with various drugs acting on the sympathetic nervous system. The tyramine-induced tension was more sensitive to guanethidine and 6-hydroxydopamine than the MeB-induced tension, while the latter was more sensitive to $Ca^{2+}-free$ PSS and reserpine. But they have similar sensitivity to prazosin. The MeB-induced tension was significantly inhibited but not abolished by 6-hydroxydopamine pretreatment. However, either tyramine or 6-hydroxydopamine could not affect the basal tension of the ring that MeB once had been tested. These results suggest that MeB-induced contractions of rabbit thoracic aorta and porcine mesenteric artery result from a release of endogenous norepinephrine from adrenergic nerve endings and are dependent in part on extracellular calcium, and that the potency of MeB to release or to deplete norepinephrine is greater than that of either tyramine or 6-hydroxydopamine.

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A Freeze-fracture Study on the Odontoblast of Dental Pulp in the Rat Incisor (흰쥐 절치치수의 Odontoblast에 관한 Freeze-Fracture 연구)

  • Kim, Myung-Kook
    • Applied Microscopy
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    • v.16 no.2
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    • pp.1-13
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    • 1986
  • The purpose of this study was to investigate the morphology and intercellular junctions of the odontoblast of dental pulp in the rat incisor by means of the freeze fracture electron microscopy. Twenty male Sprague-Dawley rats weighing $150{\sim}200g$ were used. After being anesthetized by an intraperitoneal injection of 0.5 ml sodium pentobarbital per kg in body weight(60 mg/ml) the animals were perfused with 2.5% glutaraldehyde-2% paraformaldehyde fixative in 0.1 M cacodylate buffer, pH 7.2 through the ascending aorta for one hour. The incisors were carefully extracted from the jaws and demineralized by suspending them in 0.1 M EDTA in 3% glutaraldehyde (pH 7.2) for two weeks. After demineralization, the specimens were obtained from the portion divided into five equal parts. For freeze-fracture replication, demineralized tissues were infiltrated for several hours with 10%, 25% glycerol in 0.1M cacodylate buffer as a cryoprotectant and then frozen in liquid Freon 22 and stored in liquid nitrogen. Fracturing and replication were done in Balzers BAF 400D high-vacuum freeze-fracture apparatus at $-120^{\circ}C$ under routine $5X10^{-7}$ Torr vacuum. The tissue was immediately replicated with platinum unidirectionally at $45^{\circ}$ angle and reinforced with carbon at $90^{\circ}$ angle unidirectionally or by using a rotary stage. The replication process was monitored by a quartz-crystal device. The replicas were immersed in 100% methanol overnight. The tissue was then digested from the replica by clorox (laundry bleach), placed into 5% EDTA, and washed repeatedly with distilled water. The replicas were picked up on 0.3% formvar-coated 75 mesh grids and examined in the JEOL 100B electron microscope. The results were as follows; 1. Both in thin sections and freeze-fracture replicas, three types of intercellular junctions were recognizable in the plasma membrane of odontoblast: gap junction, tight junction and desmosome-like junction. 2. The nuclear pores were evenly distributed over the nuclear envelope. The pore complex formed a ring about 70 nm in diameter. 3. Gap junctions were found between odontoblasts as well as odontoblasts and neighbouring pulp cells (fibroblast, subodontoblastic cell process, nerve-like fibre). Gap junctions, which were round, ellipsoid and pear-shaped and 600 nm in diameter, were observed in the odontoblast. 4. Numerous round and ellipsoid gap junctions could be frequently seen on the plasma membranes in cell body and apical part of the odontoblasts. On the P face, the junctions were recognized as a cluster of closely packed particles, measuring about 9 nm in diameter, and on the E face, the junctions were recognized as a shallow grooves.

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Differential Mechanisms of Vascular Relaxation between Alcohol Steamed Rhei Tangutici Radix et Rhizoma and Rhei Tangutici Radix et Rhizoma (당고특대황(唐古特大黃)의 주증(酒蒸) 여부가 혈관이완 기전에 미치는 영향)

  • Yang, Jae-Kyung;Shin, Heung-Mook
    • The Korea Journal of Herbology
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    • v.25 no.4
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    • pp.17-21
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    • 2010
  • Objectives : The aim of this study was to evaluate the differential mechnism of vasodilation of alcohol steamed Rhei Tangutici Radix et Rhizoma. (ART) and Rhei Tangutici Radix et Rhizoma. (RT) in rat thoracic aorta. Methods : Rat aortic ring preparations were mounted in organ baths with oxygenated (95% $O_2$-5% $CO_2$) Krebs-Ringer bicarbonate solutions at $37{\pm}0.5^{\circ}C$ and subjected to contractions or relaxations. Results : ART exerted vasorelaxation on phenylephrine(PE)-induced contraction in a dose dependent manner. Vasorelaxation effects of ART and RT were endothelium-independent. In the $Ca^{2+}$-free high KCl (60 mM) baths, the contraction of aortic rings induced by accumulative addition of $Ca^{2+}$ (0.3-10.0 mM) was significantly reduced by pre-treatment with both ART and RT for 10 min. The magnitude of vasodilatation was biggerin ART. Moreover, verapamil ($0.001{\mu}M$) and diltiazem ($10{\mu}M$), voltage operative $Ca^{2+}$channel blockers, attenuated the relaxation effect of ART but not that of RT. In the absence of extracellular $Ca^{2+}$, pre-incubation of the aortic rings with RT ($1.0mg/m{\ell}$) significantly reduced the contraction caused by PE but not that of ART. $K^+$ channel inhibitors such as glibenclamide (Gli, $10^{-5}M$), tetraethylammonium (TEA, 1 mM) and 4-aminopyridine (4-AP, 0.2 mM) significantly reduced the ART's vasorelaxation efficacy, but not that of RT. However, the relaxation effects of ART and RT were not inhibited by pre-treatment with indomethacin ($10^{-5}M$), and atropine ($10^{-6}M$). Conclusions : These results suggest that the endothelium-independent relaxation is due to inhibition of $Ca^{2+}$ influx via the suppression of $Ca^{2+}$ release from intracelluar store in RT but via both voltage operative $Ca^{2+}$channel blockage and $K^+$ channel activation in ART.

Study on the Effects of Jiaweicitaowan (加味慈桃丸) Ingredients on Angiogenic Inhibition (가미자도환(加味慈桃丸) 구성약물(構成藥物)의 혈관신생(血管新生) 억제효과(抑制效果)에 관한 연구(硏究))

  • Wang, Teh-Chung;Kang, Hee;Shim, Bum-Sang;Kim, Sung-Hoon;Choi, Seung-Hoon;Ahn, Kyoo-Seok
    • Journal of Korean Traditional Oncology
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    • v.11 no.1
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    • pp.75-93
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    • 2006
  • Jiaweicitaowan (JWCTW) has been used to inhibit recurrence and metastasis of cancer in clinical practice. Further study has shown its anti-metastatic and anti-angiogenic effects. By applying in vitro and in vivo anti-angiogenic evaluation model, the author assayed the each ingredients of JWCTW. The author performed the following experiments and the results are listed as below: Cell viability assay showed that the viability was almost identical between that of the control and that of the ingredients extract 40 ${\mu}g/m{\ell}$ treated, except of hexane fraction of Curcumae Radix (40 ${\mu}g/m{\ell}$, 2.0% of control), ethylacetate fraction (40 ${\mu}g/m{\ell}$, 26.7%), butanol fraction (20 ${\mu}g/m{\ell}$, 87.2%; 40 ${\mu}g/m{\ell}$, 12.5%) of Cremastrae appendiculatae Tuber, water fraction of Persicae Semen (40 ${\mu}g/m{\ell}$, 82.7%), ethylacetate fraction of Hippocampus (40 ${\mu}g/m{\ell}$, 85.3%). The results of gelatin zymogram assay showed that the ingredients of JWCTW decreases the gelatinolytic activity of MMP-9 from ECV304, at the concentration of 10 ${\mu}g/m{\ell}$. In in vitro invasion assay, the ingredients of JWCTW effectively inhibited the invasion of cancer cells as compared with the control (+PMA) groups. In capillary-like tube formation assay, the hexane and ethylacetate fractions of Curcumae Radix, Cremastrae appendiculatae Tuber and Persicae Semen showed the dramatic inhibition effects on tube formation of ECV304 at the concentration of 40 ${\mu}g/m{\ell}$. In ex vivo rat aortic ring assay, the hexane and ethylacetate fractions of Curcumae Radix, Cremastrae appendiculatae Tuber and Persicae Semen showed the inhibition effects on angiogenesis of rat aorta at the concentration of 40 ${\mu}g/m{\ell}$. According to the above research, the anti-angiogenic effects of the ingredients of JWCTW was proved and it suggested that the more effective prescription for anti angiogenesis could be developed.

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Experimental Study of WhaYoungJiTongTang(Heyingjitongtang)on the anti-angionesis (화영지통탕(和營止痛湯)의 혈관신생억제효과(血管新生抑制效果)에 관한 실험적(實驗的) 연구(硏究))

  • Kim, In-Seok;Park, Joon-Hyuck;Kang, Hee;Kim, Sung-Hoon;Yu, Young-Beob;Shim, Bum-Sang;Choi, Seung-Hoon;Ahn, Koo-Seok
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.7 no.1
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    • pp.61-75
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    • 2001
  • The purpose of this study is to prove the angiogenesis effects of WhaYoungJiTongTang (hereinafter referred to as the 'WYJTT'). For the study, by utilizing liver cancer cell line; SK-HEP-1, lung cancer cell line: A549, stomach cancer cell line: AGS and bovine capillary endothelial cell: BCE, the effects of the WYJTT on toxicity and proliferation ability of cells and the effects on anti-angiogenesis of bovine capillary endothelial cell and of mice's aorta were studied. 1. Cell viability assay In comparison with the control group, when $100{\mu}g/ml$ of WYJTT was injected, the viability was reduced in SK-Hep-1, $400{\mu}g/ml$ in A549 and $200{\mu}g/ml$ in AGS. 2. Cell proliferation assay In comparison with the control group, when $600{\mu}g/ml$ of WYITT was injected, DNA synthesis was reduced to 35.1% in the SK-Hep-1, 56.0% in A549, and 25.8% in BCE (bovine capillary endothelial cell); and when $400{\mu}g/ml$ was injected, DNA synthesis was reduced to 12.1 in AGS. 3. Tube formation assay In the event that BCE is injected with WYJTT in each of its content gradient, the anti-angiogenesis was effective in amounts of $400{\mu}g/ml$ with 6 hours of the treatment. 4. Aortic ring assay In comparison with the control group, the angiogenesis was restricted to the remarkable degree in amount of $200{\mu}g/ml$: 10% in $400{\mu}g/ml$; and fully inhibited in each of $800{\mu}g/ml$ and $1600{\mu}g/ml$. As a result of the experiments mentioned above, WYJTT showed its anti-angiogenesis effects against cancer cell line.

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