• International Journal of Vascular Biomedical Engineering
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• v.1 no.2
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• pp.13-19
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• 2003

Endothelial release of nitric oxide (NO) contributes to the regulation of vascular tone by inducing vascular relaxation. To estimate the blood flow-dependent nitric oxide level and half-life (T1/2) of nitric oxide in vivo state, we investigated the change of aortic NO currents during the change of aortic blood flow rate using NO-selective electrode system and electromagnetic flowmeter in the aorta of anesthetized rats. Resting mean aortic blood flow rate was $49.6{\pm}5.6ml/min$ in the anesthetized rats. NO currents in the aorta were increased by the elevation of blood pressure and/or blood flow rate. When the aortic blood flow was occluded by the clamping, aortic NO currents were decreased. The difference of NO concentration between resting state and occluded state was $1.34{\pm}0.26{\mu}M$ (n=7). This NO concentration was estimated as blood flow-dependent nitric oxide concentration in the rats. Also, while the aortic blood flow was occluded, NO currents were decreased with exponential pattern with $12.84{\pm}2.15$ seconds of time constant and $7.70{\pm}1.07$ seconds of half-life. To summarize, this study suggested that blood flow-dependent NO concentration and half-life of nitric oxide were about $1.3{\mu}M$ and 7.7 seconds, respectively, in the aorta of anesthetized rats. The nitric oxide-selective electrode system is useful for the direct and continuous measurement of NO in vivo state.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1057-1066
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• 1990

The possible relationship between pulmonary vascular pathologic changes and an increased pulmonary blood flow and pulmonary blood pressure has been the subject of investigation for many years. In an attempts to study the effects of increased pulmonary blood flow. long-term observations have been made in neonatal goats in which the total pulmonary vascular bed was restricted by means of ligation of left pulmonary artery, thereby diverting the total right ventricular output through the right lung. The left pulmonary artery and patent ductus arteriosus were ligated in 6 neonatal goats of under 3 weeks of age, and the goats were put to death at interval between 1 and 7 months of age. Pulmonary arterial development in both right and left lungs was studied by applying quantitative morphometric techniques, and compared with control group of goats between 1 and 6 months of age. The axial pulmonary artery and its branches were larger in the right lung than in the control group in all animals, and they were abnormally small in the left lung. In the right lung, arteries smaller than 50\ulcornerm showed abnormal increase in `% wall thickness’ in postoperative 2,3,5 and 6th months[p<0.05]. The proportion of non-muscular arteries was over 50% at postoperative 1st month in both right and left lungs, but an increase in proportion of partially muscular and wholly muscular arteries occurred thereafter. The ratio of alveoli/arteries was lower than normal in the right lung of postoperative 1st month[p<0.05], but was elevated thereafter. The failure to perfuse one pulmonary artery in neonatal goats changed growth and development of both lungs.

• The Journal of Korean Physical Therapy
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• v.20 no.4
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• pp.35-42
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• 2008

Purpose: Alterations in the structure and function of vascular smooth muscle cells (VSMCs) are important in cardiovascular disease and maintaining chronic hypertension. Chronic hypertension is associated with changes in vascular smooth muscle tone. The spontaneous or myogenic tone of a blood vessel reflects the ability to adapt smooth muscle tone to changes in transmural pressure. However, the intracellular signaling mechanisms involved in myogenic tone are not fully understood. Methods: Here, we investigated the relationship between mitogen-activated protein kinases (MAPKs) and phosphatidylinositol-3 kinase (PI3K) in isometric contraction and enzymatic activity using muscle strips from rats made hypertensive with aldosterone-analogue deoxycorticosterone acetate (DOCA) salts. Results: Changes in myogenic tone and intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) were different after physiological salt solution (PSS) in normotensive and hypertensive rats. The myogenic tone and quiescent phosphorylation induced by the PSS treatment were inhibited by 10 ${\mu}$M PD098059, an extracellular-regulated protein kinase 1/2 (ERK1/2) inhibitor, and 10 ${\mu}$M wortmannin, an inhibitor of PI3K, in hypertensive rats. Conclusion: The development of DOCA-induced hypertension is associated with altered isometric contractions and $[Ca^{2+}]_i$ via changes in activation of ERK1/2 and PI3K after DOCA-salt treatment. Therefore, ERK1/2 and PI3K activity affect hypertension and may be suitable targets for physical therapy in cardiovascular disease.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.705-713
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• 2020

Arteriosclerosis is a disease in which blood circulation is impaired due to loss of elasticity as blood vessels become narrower, and is a potential cause of recently increasing cardiovascular and cerebrovascular diseases. Carotid ultrasound is used as a predictor of cardiovascular and cerebrovascular diseases by evaluating the degree of atherosclerosis. Therefore, this paper attempted to investigate the correlation between the increase in the thickness of the inner media and various clinical variables in carotid ultrasound. Patients with carotid ultrasound findings were classified into three stages: mild intima thickening, sclerosis, and significant stenosis. CAVI (Carotid Ankle Vascular Index: vascular age) data measured in the degree and physical characteristics of the carotid artery(gender, age, body mass index, blood pressure), blood test(total cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, creatine phosphokinase, fasting blood sugar), and arteriosclerosis test were collected. It was confirmed that the carotid intima thickness was correlated with variables such as hypertension, hyperlipidemia, and BMI, and also correlated with the risk factors of cardiovascular disease as CAVI increased.

• Natural Product Sciences
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• v.20 no.3
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• pp.216-225
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• 2014

The present study was designed to investigate whether ethylacetate (EtOAc) fraction extracted from Rubus coreanum affect the contractility of the isolated thoracic aortic strips and blood pressure of normotensive rats. The EtOAc fraction ($400{\mu}g/mL$) significantly depressed both phenylephrine (PE, $10{\mu}M$)- and high $K^+$ (56 mM)-induced contractile responses of the isolated thoracic aortic strips in a concentration-dependent fashion. In the simultaneous presence of L-NAME (an inhibitor of NO synthase, $300{\mu}M$) and EtOAc ($400{\mu}g/mL$), both PE- and high $K^+$-induced contractile responses were recovered to the corresponding control level in comparison with inhibition of EtOAc-treatment alone. Moreover, in the simultaneous presence of EtOAc after pretreatment with 0.4% CHAPS, both PE- and high $K^+$-induced contractile responses were recovered to the corresponding control level compared to the inhibitory response of EtOAc-treatment alone. Also, in anesthetized rats, EtOAc fraction (0.3~3.0 mg/kg) injected into a femoral vein dose-dependently produced depressor responses. This hypotensive action of EtOAc fraction was greatly inhibited after treatment with phentolamine (1 mg/kg), chlorisondamine (1 mg/kg), L-NAME (3 mg/kg/30 min) or sodium nitroprusside ($30{\mu}g/kg/30 min$). Intravenous infusion of EtOAc fraction (1.0~10.0 mg/kg/30 min) markedly inhibited norepinehrine-induced pressor responses. Taken together, these results demostrate that EtOAc causes vascular relaxation in the isolated rat thoracic aortic strips as well as hypotensive action in anesthetized rats. These vasorelaxation and hypotension of EtOAc seem to be mediated at least by the increased NO production through the activation of NO synthase of vascular endothelium, and the inhibitory adrenergic modulation.

• Journal of Haehwa Medicine
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• v.15 no.2
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• pp.263-272
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• 2006

Purpose Brain vessles have autoregulation function, so even when perfusion pressure drops, cerebral blood flow remain stable by vasodilation. Latest research on this reserve of cerebral vessels is being done using TCD, which measures the reserve of the vessels. We did a research comparing cerebral vessel and peripheral vessel reserve between Taeumin, who are more likely to suffer CVA, and the normal. We observed blood flow of Internal carotid artery siphon and radial indicis artery of the two group with TCD. Method We picked 20 people out of patients diagnosed as cerebral infarction at Cheon-An Oriental hospital of Daejeon University. They were diagnosed as Taeumin with QSCCII questionnaire and constitutional differentiation. Using TCD, we measured highest blood flow rate, mean blood flow and asymmetric counting blood flow of Internal carotid artery siphon and radial indicis artery at rest. And then we measured again after stimulating cerebral vessels, by triggering hypercapnia by self apnea and peripheral vessels by palm heating. Result At rest, mean blood flow rate of Internal carotid artery siphon showed significant decrease compared to control group. Blood flow rate of Internal carotid artery siphon after hypercapnia showed significant decline in highest blood flow rate and mean blood flow compared to control group. Cerebral vessel reaction after the hypercapnia induction showed great change in experiment group than the control group. Peripheral vessel reaction after palm heating showed significant decline in experiment group compared to control group. Conclusion In conclusion, measuring the alteration of blood flow used in diagnosing cerebral infarction, is more sensitive when vessel stimulation is done. Non-invasive TCD is effective especially in case of Taeumin who are more likely to suffer vascular disorder than others.

• Journal of Ginseng Research
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• v.38 no.4
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• pp.244-250
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• 2014

Background: Panax ginseng has distinct and impressive health benefits, such as improved blood pressure and immune system functioning. Rg3-enriched Korean Red Ginseng (REKRG) isolated from Korean Red Ginseng contains a high percentage of Rg3. Methods: In this study, we examined the effects of REKRG on endothelial cell nitric oxide synthase (eNOS) activation and adhesion molecules in endothelial cells and vascular function in rats. Results: REKRG dose-dependently increased eNOS phosphorylation and nitric oxide (NO) production in endothelial cells. In addition, REKRG markedly inhibited the tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-mediated induction of intercellular adhesion molecule (ICAM)-1 and cyclooxygenase (COX)-2 expressions in endothelial cells. REKRG improved endothelium-dependent vasorelaxation in the Wistar-Kyoto (WKY) rat and spontaneously hypertensive rats (SHRs) compared with controls. Furthermore, REKRG treatment for 6 weeks increased serum NO levels and reduced the mean aortic intima-media thickness compared with controls. Conclusion: Taken together, these results suggest that REKRG increased vascular function and improved immune system functioning. Therefore, REKRG is a very useful food for preventing or improving various cardiovascular diseases.

• Molecules and Cells
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• v.37 no.11
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• pp.804-811
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• 2014

The protease-activated receptor (PAR)-2 is highly expressed in endothelial cells and vascular smooth muscle cells. It plays a crucial role in regulating blood pressure via the modulation of peripheral vascular tone. Although several mechanisms have been suggested to explain PAR-2-induced hypotension, the precise mechanism remains to be elucidated. To investigate this possibility, we investigated the effects of PAR-2 activation on N-type $Ca^{2+}$ currents ($I_{Ca-N}$) in isolated neurons of the celiac ganglion (CG), which is involved in the sympathetic regulation of mesenteric artery vascular tone. PAR-2 agonists irreversibly diminished voltage-gated $Ca^{2+}$ currents ($I_{Ca}$), measured using the patch-clamp method, in rat CG neurons, whereas thrombin had little effect on $I_{Ca}$. This PAR-2-induced inhibition was almost completely prevented by ${\omega}$-CgTx, a potent N-type $Ca^{2+}$ channel blocker, suggesting the involvement of N-type $Ca^{2+}$ channels in PAR-2-induced inhibition. In addition, PAR-2 agonists inhibited $I_{Ca-N}$ in a voltage-independent manner in rat CG neurons. Moreover, PAR-2 agonists reduced action potential (AP) firing frequency as measured using the current-clamp method in rat CG neurons. This inhibition of AP firing induced by PAR-2 agonists was almost completely prevented by ${\omega}$-CgTx, indicating that PAR-2 activation may regulate the membrane excitability of peripheral sympathetic neurons through modulation of N-type $Ca^{2+}$ channels. In conclusion, the present findings demonstrate that the activation of PAR-2 suppresses peripheral sympathetic outflow by modulating N-type $Ca^{2+}$ channel activity, which appears to be involved in PAR-2-induced hypotension, in peripheral sympathetic nerve terminals.

• Journal of Yeungnam Medical Science
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• v.20 no.1
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• pp.1-12
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• 2003

Ischemic stroke is among the principal causes of death and disability in the elderly. Although control of blood pressure, decreased cigarette smoking, and modified dietary habits are among important reasons for stroke decline, the use of antithrombotic therapy, rigorously prescribed. Several antiplatelet agents are approved to reduce the risk of recurrent stroke. Aspirin is the best-studied and most widely used antiplatelet agent for stroke prevention; it provides approximately 15% to 25% relatively risk reduction for secondary prevention of stroke or the major vascular death. Combining 2 antiplatelet agents with different mechanism of action was demonstrated to provide a substantial increase in efficacy in several studies. Anticoagulation should be considered first with potential cardiac sources of embolism. Heparin reduces development of erythrocyte-fibrin thrombi that form in regions of vascular stasis especially within the heart, in severely stenosed arteries sometimes engrafted on white thrombi, in acute arterial occlusion. Heparin should not be indiscriminately given to all acute brain ischemia patients, but may contribute to treatment of large artery occlusion and severe stenosis, cardiogenic embolism with a high acute recurrence risk, and dural sinus and cerebral venous thromobosis.

• Genomics & Informatics
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• v.12 no.3
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• pp.127-133
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• 2014

Gastritis is a major disease that has the potential to grow as gastric cancer. Gastric cancer is a very common cancer, and it is related to a very high mortality rate in Korea. This disease is known to have various reasons, including infection with Helicobacter pylori, dietary habits, tobacco, and alcohol. The incidence rate of gastritis has reported to differ between age, population, and gender. However, unlike other factors, there has been no analysis based on gender. So, we examined the high risk factors of gastritis in each gender in the Korean population by focusing on sex. We performed an analysis of 120 clinical characteristics and genome-wide association studies (GWAS) using 349,184 single-nucleotide polymorphisms from the results of Anseong and Ansan cohort study in the Korea Association Resource (KARE) project. As the result, we could not prove a strong relation with these factors and gastritis or gastric ulcer in the GWAS. However, we confirmed several already-known risk factors and also found some differences of clinical characteristics in each gender using logistic regression. As a result of the logistic regression, a relation with hyperlipidemia, coronary artery disease, myocardial infarction, hyperlipidemia therapy, hypotensive or antihypotensive drug, diastolic blood pressure, and gastritis was seen in males; the results of this study suggest that vascular disease has a potential association with gastritis in males.