• Korea-Australia Rheology Journal
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• 제21권1호
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• pp.39-46
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• 2009

Atherosclerosis is a disease that narrows, thickens, hardens, and restructures a blood vessel due to substantial plaque deposit. The geometric models of the considered stenotic blood flow are three different types of constriction of cross-sectional area of blood vessel; 25%, 50%, and 75% of constriction. The computational model with the fluid-structure interaction is introduced to investigate the wall shear stresses, blood flow field and recirculation zone in the stenotic vessels. The velocity profile in a compliant stenotic artery with various constrictions is subjected to prescribed physiologic waveform. The computational simulations were performed, in which the physiological flow through a compliant axisymmetric stenotic blood vessel was solved using commercial software ADINA 8.4 developed by finite element method. We demonstrated comparisons of the wall shear stress with or without the fluid-structure interaction and their velocity profiles under the physiological flow condition in the compliant stenotic artery. The present results enhance our understanding of the hemodynamic characteristics in a compliant stenotic artery.

• 한국산학기술학회논문지
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• 제13권5호
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• pp.2285-2290
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• 2012

동맥경화는 혈관 안에서 콜레스테롤의 침착 때문에 혈관이 좁아지거나, 딱딱해 지거나, 두꺼워 지게 되는데, 이런 현상이 심해지게 되면 동맥은 단단해져서 혈액이 원활히 통과하지 못하게 되고 심하면 사망 까지 이르게 되는 것이다. 본 연구에서는 복대동맥에서의 동맥경화가 진행되는 것을 탄성 혈관 일 때와 강성 혈관 일 때 각각 협착률이 혈관 직경의 20과 45%로 설정하고 속도와 압력 변화를 살펴보기 위하여 유한 요소 해석을 이용하여 모델링을 하였다. 혈관이 탄성 혈관일 때 속도와 압력 값은 협착률이 혈관 직경의 20%일 때 보다 45%일 때 더 높게 나타났으며, 강성 혈관에서 속도와 압력 값은 협착률이 혈관 직경의 20%일 때보다 45%에서 더 높았다. 협착률이 혈관 직경의 20과 45%인 탄성 혈관에서 재순환영역이 나타났다. 본 연구결과 혈관 협착에 따른 혈류역학적 특징을 이해하는데 도움이 될 것으로 판단된다.

• BMB Reports
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• 제44권6호
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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.

• 대한기계학회논문집B
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• 제32권11호
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• pp.891-896
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• 2008

In the present computational study, simple stenotic artery models using pulsatile flow condition were investigated. A 1 Hz non-reversing sinusoidal velocity for pulsatile flow was imposed at the flow inlet and the corresponding Womersley number based on the vessel radius is 2.75. The simple stenotic geometries have been used that consist of 25%, 50% and 75% semicircular constriction in a cylindrical tube. In this paper, numerical solutions are presented for a first harmonic oscillatory flow using commercial software ADINA 8.4. As stenosis and Reynolds number increase, the maximum wall shear stress(WSS) increases while the minimum WSS decreases. As the stenotic rate increases, the pressure drop at the throat severely decreases to collapse the artery and plaque. It is found that the fluid mechanical disturbances due to the constriction were highly sensitive with rate of stenosis and Reynolds number. When Reynolds number and stenosis increase, the larger recirculation region exists. In this recirculation region the possibility of plaque attachment is increasingly higher. The present results enhance our understanding of the hemodynamics of a stenotic artery.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.178.3-178.3
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• 2003

P2X receptors are ligand gated cation channels activated by the binding of extracellular adenosine 5'-triphosphate (ATP) and classified into 7 subtype families. $P2X_1$ receptors are abundantly expressed in smooth muscle mediates blood vessel and mediate constriction upon binding of neuronal ATP. The activation of $P2X_3$ receptor by ATP has been known to initiate the pain signaling in the peripheral nervous system, which is involved in chronic inflammatory nociception and neuropathic pain by nerve injury. (omitted)

• 미생물학회지
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• 제44권4호
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• pp.282-288
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• 2008

혈관이 좁아지거나 막혀서 생기는 허혈은 심장, 뇌, 다리와 같은 인체의 여러 장기에 영향을 미친다. 최근 혈관신생 분야에서 많은 진전이 있어 기존 치료법으로 치료가 되지 않는 허혈성 환자들의 치료 가능성에 대한 기대가 많아졌다. 혈관형성은 여러 개의 인자들과 세포들이 관여하는 복잡한 과정이기 때문에, 한 개의 인자보다는 여러 인자들을 병합하는 요법이 점점 많이 시도되고 있는데, 이런 병합요법의 한 예로 전사인자를 전달하는 전략을 생각할 수 있다. 이에 본 연구에서는 cardiac ankyrin repeat protein (CARP)의 유전자를 대상으로 그 혈관신생 능력을 혈관내피세포에서 조사하였다. 아데노바이러스 벡터 내에 human CARP의 cDNA를 클로닝하여 재조합 아데노바이러스를 제조하였으며, 이를 이용한 유전자 전달실험 결과, CARP 유전자 전달 군에서 유의하게 혈관내피세포의 중식과 모세관 구조 형성, 그리고 vascular endothelial growth factor의 발현 등을 증가시킴을 확인하였다. 본 연구 결과는 CARP가 혈관신생 연구의 새로운 목표 유전자로서 그 기능에 대한 많은 연구가 필요함을 뒷받침해준다.

• 한국식품영양학회지
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• 제36권6호
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• pp.572-580
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• 2023

Hypertension is characterized by excessive renin-angiotensin system activity, leading to blood vessel constriction. Several synthetic compounds have been developed to inhibit renin and angiotensin-converting enzyme (ACE). These drugs often have adverse side effects, driving the exploration of plant protein-derived peptides as alternative or supplementary treatments. This study assessed the phenolic compound and amino acid content and the antioxidant and antihypertensive activity of 5 South Korean staple crops. Sorghum had the highest phenolic compound content and exhibited the highest antioxidant activity. Millet grains, particularly finger millet (38.86%), showed higher antihypertensive activity than red beans (14.42%) and sorghum (17.16%). Finger millet was found to contain a large proportion of branched-chain, aromatic, and sulfur-containing amino acids, which are associated with ACE inhibition. In particular, cysteine content was positively correlated with ACE inhibition in the crops tested (r=0.696, p<0.01). This study confirmed that the amino acid composition was more correlated with the antihypertensive activity of grains than the phenolic compound content. Finger millet mainly contained amino acids, which have higher ACE inhibitory activity, resulting in the strongest antihypertensive activity. These findings underscore the antihypertensive potential of select crops as plant-based food ingredients, offering insight into their biological functions.