• Annals of Clinical Neurophysiology
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• v.1 no.1
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• pp.55-59
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• 1999

Vasoconstriction of intracerebral arteries is the leading cause of delayed cerebral infarction and mortality following aneurysmal subarachnoid hemorrhage. Transcranial Doppler studies show and increase in the flow velocities of basal cerebral arteries, which usually start around day 4 following a subarachnoid hemorrhage, and peaking by days 7 to 14. Angiographic studies confirm the presence of at least some degree of MCA vasospasm when the flow velocities are higher than 100 cm/sec. Mean velocities in the 120 to 200 cm/sec range correspond to 25 to 50% luminal narrowing. MCA and ACA vsospasm is detected with around 90% specificity. Sensitivity is 80% and 50% respectively. A 200cm/sec threshold and rapid flow velocity increase exceeding 50 cm/sec on consecutive days, has been associated with subsequent infarction. Transcranial Doppler is also used to monitor the effects of endovascular treatment of vasospasm. Flow velocities decrease following successful angioplasty or papaverine infusion. Overall, transcranial Doppler studies are considered to have acceptable accuracy for the evaluation of vasospasm in aneurysmal subarachnoid hemorrhage, with limitations that have to be taken into consideration in the clinical setting.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.193-193
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• 1996

Endothelin-1, which is a peptide originally isolated from cultured porcine aortic cell, has been found to play a crucial role in potentiating the vasoconstriction mitogenesis, and chemotaxis. In the present study, we examined the level of endothelin-1 in the brain, spinal cord and blood from rat with experimental allergic encephalomyelitis(EAE). At the peak stage of EAE(grade 3), endothelin-1 level in the spinal cord of rat with EAE increased two folds as compared with that of sham-treated rats, and subsequently decreased to the level of control at the recovery stage. In the endothelin-1 immunocytochemistry, endothelin-1 immunopositive cells and ED-1, macrophage marker immunopositive cells observed in the spinal cord of peak stage(grade 3). These Findings suggest that endothelin-1 play the important role in progression of EAE.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.1-8
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• 2013

Understanding the cellular and molecular mechanisms involved in the development and progression of pulmonary hypertension (PH) remains imperative if we are to successfully improve the quality of life and life span of patients with the disease. A whole plethora of mechanisms are associated with the development and progression of PH. Such complexity makes it difficult to isolate one particular pathway to target clinically. Changes in intracellular free calcium concentration, the most common intracellular second messenger, can have significant impact in defining the pathogenic mechanisms leading to its development and persistence. Signaling pathways leading to the elevation of $[Ca^{2+}]_{cyt}$ contribute to pulmonary vasoconstriction, excessive proliferation of smooth muscle cells and ultimately pulmonary vascular remodeling. This current review serves to summarize the some of the most recent advances in the regulation of calcium during pulmonary hypertension.

• 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.

• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.282-286
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• 1999

OQ-21을 암·수 ICR계 마우스에 복강투여 하여 급성독성을 측정한 결과 최대용량 투여군에서도 사망한 동물은 관찰되지 않았다. 그리고 시험동물을 부검하여 육안 관찰한 결과 OQ-21 투여군은 대조군과 전혀 차이가 없었고 실제 독성도 비교적 낮은 것으로 판단된다. 또한 OQ-21이 혈과에 수축 반응에 영향을 미치는 지를 연구한 결과 용량 의존적으로 phenylephirne에 의한 혈관 수축을 증가시킴을 관찰하였다. 이상의 결과로부터 OQ-21은 급성독성이 약한 것으로 생각되지만 혈관 수축에 미치는 영향은 앞으로 인체 안전성에 관하여 검토하여야 할 과제로 사료된다.

• Journal of Korean Physical Therapy Science
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• v.5 no.4
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• pp.817-830
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• 1998

The purpose of this study is to investigate the relationship between effects of TENS (Transcutaneous Electrical Nerve Stimulation) and IFC(Interferrential Current Therapy) to the change of body surface temperature. Cases are 22 normal persons and 22 patients with low back pain. Digital Infrared Thermal Imaging system was used for the detection of body surface temperature. 50Hz in frequency and 25-35mA in intensity were applied to TENS and IFC, 15 and 10 minutes on each. The results were follows ; 1. TENS and IFC has on effect of decreasing surface temperature, which would be from cardiovascular factors. (P<0.001) 2. The influence of IFC to the body surface temperature is greater than TENS, and it seems to be vasoconstriction of sympathetic activity. 3. There were no significant differences of body surface temperature between the two groups before and after electrical stimulation.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2009.04a
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• pp.137-150
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• 2009

Background: Heart failure can develop secondary to various heart diseases (e.g. mitral valvular insufficiency, congenital heart defects, heart worm infection). The clinical signs of heart failure can be confused with those of other conditions, such as respiratory disease. Therefore, specific, sensitive, rapid and inexpensive blood tests for heart failure are desirable. Cardiac troponins, natriuretic peptides and cytokines have been more recently used as indicators of heart disease in humans and animals. These peptides are sensitive to changes in vasoconstriction and dilation within the heart and are used for the diagnosis and prognosis of heart failure. Methods: Previously developed and newly developed cardiac biomarkers will be discussed for understating clinical implications and diagnostic values in heart diseases in small animals

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.35-35
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• 2002

The large conductance $Ca^{2＋}$ -activated $K^{＋}$ channels ($BK_{Ca}$) in vascular smooth muscle have been considered to function as a negative feedback in pressure-induced vasoconstriction. In the present study, the function of cytoskeletons in the regulation of $BK_{Ca}$ and its stretch sensitivity was investigated. Using the inside-out patch clamp technique, we recorded single channel activities of $BK_{Ca}$ with 150 mM KCl in the bath solution (pCa=6.5).(omitted)itted)

• The Korean Journal of Physiology
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• v.1 no.2
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• pp.215-230
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• 1967

It has been suggested by Krag and Kountz (1950), Horvath et al. (1955) and Spurr et al. (1955) that the mechanism for prevention of heat loss is less efficient in the aged than in the young. In addition, they observed that peripheral vasoconstriction occurred more rapidly and more intensively in the aged people in response to the cold stimulus. Although it is not clear on the basis of these reports whether the Physical insulation of the aged people in cold would be different from the younger, it is evident that the vascular reactivity in response to cold seems to be altered in the aged people. Hence this investigation was undertaken to investigate the physical insulation of the aged people in a systemic manner by water immersion method which has been successfully applied to the Eskimos and Korean diving women by Rennie et al.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.4 s.40
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• pp.447-451
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• 1991

Effects of insulation after exposure of the extremities on the temperature regulation in clothed men were studied. Experiment was carried out with six males in a climatic chamber fixed at $10^{\circ}C$, $55\%$ R.H. treated with Type A (face only was exposed) and Type B (face and half of the extremities were exposed). Mean skin temperature fell greater in Type B due to intense vasoconstriction than in Type A. Rectal temperature rose a little in Type B and resumed in Type A without any significant differences in metabolism between two types of clothing. These findings suggest that Type B is more effective in physiological defense to the cold stimuli than Type A at least at $10^{\circ}C$.