• Korean Journal of Clinical Laboratory Science
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• v.43 no.4
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• pp.138-144
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• 2011

Exaggerated blood pressure response during exercise has been found to increase the risk of future hypertension, left ventricular hypertrophy, cerebrovascular stroke, and CVD (cardiovascular disease) death. The aim of this study was to evaluate exercise capacity, cardiovascular factors in exaggerated blood pressure response during treadmill exercise testing. For research subjects, 72 subjects (normal blood response: 49 subjects, exaggerated blood response: 23 subjects) who received treadmill exercise test at J General Hospital were selected in this study. Exaggerated SBP (systolic blood pressure) response was defined as an SBP of 210 mmHg or greater during a maximal treadmill exercise test. The group with an exaggerated SBP response showed significantly higher values for RPP (rate pressure product) compared with the group with a normal SBP response. Subjects with METs (metabolic equivalents) had lower exaggerated SBP response than normal SBP response group. Subjects with recovery SBP had delayed exaggerated SBP response than normal SBP response group. Exaggerated SBP response to exercise is negative correlation with METs.

• The Korean Journal of Nuclear Medicine
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• v.12 no.1
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• pp.9-16
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• 1978

It has been suggested that plasma renin activity (PRA) and its response to volume depletion may be abnormal in that it shows little or exaggerated change in patients with chronic renal failure and hypertension. Intravenous furosemide stimulation test was performed in 46 control subjects and 51 patients with chronic renal failure and/or malignant hypertension in order to evaluate PRA response. In contrast to the consistent increase in PRA in control subjects (from $2.5{\pm}1.95\;to\;4.5{\pm}2.51ng/ml/hr$), no consistent increase was observed in patients with chronic renal failure, especially in those who showed favorable response to antihypertensive therapy (from $2.5{\pm}2.21\;to\;2.9{\pm}2.46ng/ml/hr$). But poor responder to antihypertensive treatment showed considerably higher PRA before and after furosemide stimulation (from $4.9{\pm}1.96\;to\;6.4{\pm}1.71ng/ml/hr$) than the responder group did. Moreover, this group seemed to retain the ability to increase PRA in response to intravenous furosemide stimulation. Thus it became apparent that responder group was unable to increase PRA normally in response to furosemide as well as volume depletion, while poor responder seemed to retain that ability. Thus intravenous furosemode may serve as a convenient way to differenfiate those who might be benefited by conservative antihypertensive measures from those who would require more drastic measures such as bilateral nephrectomy for their optimal blood pressure control.

• The Korean Journal of Physiology
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• v.23 no.1
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• pp.129-138
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• 1989

In an attempt to characterize the ventral root afferent fibers, arterial blood pressure responses to stimulation of the ventral root (VR) were observed in anesthetized cats. Effects of the morphine administered either intravenously or direct spinally and of the spinal lesions on the pressor responses were compared. Followings are the results obtained. 1) Stimulation of the VR with C-strength, high frequency stimuli evoked a marked pressor response. No depressor response, which had been reported during peripheral nerve stimulation, was observed during VR stimulation with low frequency. 2) Acute cervical spinalization abolished the pressor response, indicating the involvement of supraspinal mechanism. 3) The ascending spinal pathways of the pressor response were located in the dorsolateral funiculus bilaterally. 4) Intravenously administered morphine exaggerated the pressor response to VR stimulation, while direct spinally administered morphine suppressed it. From the above results it was concluded that the ventral root afferent fibers have more similar properties to muscular C-afferent fibers than to cutaneous C-fibers.

• The Korean Journal of Pharmacology
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• v.19 no.1
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• pp.61-69
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• 1983

Hypothermia is an essential preparatory procedure for cardiac surgery, which lows the metabolic rate and myocardial oxygen demand. However, hypothermia itself is a stress enough to change the tonus of sympathoadrenal system, especially the cardiovascular responses to the catecholamines. It is reported that the positive chronotropic and inotropic response of catecholamines is exaggerated during hypothermia because of decreased norepinephrine uptake at the junctional cleft or decreased catecholamine metabolism. On the other hand, there are evidences of diminished catecholamines responses in low temperature ana further, interconversion of adrenergic receptors is also suggested. Present investigation was planned to observe the cardiovascular changes and its responses to catecholamines during surface hypothermia in cat. Healthy mongrel cats, weighing $2{\sim}3\;kg$, anesthetized with secobarbital(30 mg/kg), were permitted to hypothermia by external cooling technic. Esophageal temperature, ECG (lead II), heart rate, left ventricular pressure with dP/dt, carotid artery pressure and left ventricular contractile force were monitored with Polygragh (Model 7, Grass), and the respiration was maintained with artificial respirator (V 5 KG, Narco). Followings are summarized results. 1) Surface cooling caused progressive decrease of body temperature and reached $l8.8{\pm}0.8^{\circ}C$ and $16.9{\pm}0.6^{\circ}C$ in 120 and 150 min respectively, after immersion into ice water, and ventricular fibrillation was developed at $20.4{\pm}0.65^{\circ}C$. 2) Heart rate, blood pressure and myocardial contractility were decreased after initial increase as the body temperature falls. 3) Systolic and diastolicdd P/dt of left ventricular pressure were decreased and that the decrement of diastolic dP/dt was more marked. 4) On ECG, ST depression, Twave inversion and prolongation of PR interval were prominent in hypothermia, and moreover, the prolongation of PR interval was marked just prior to the development of ventricular fibrillation. 5) The cardiovascular responses to catecholamines, especially to isoproterenol, were suppressed under hypothermia.

• Journal of Life Science
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• v.22 no.4
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• pp.532-537
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• 2012

We investigated the effect of smoking on cardiovascular responses during acute dynamic exercise. Eleven college students who had been smoking (duration of smoking: $7.45{\pm}0.90$ years; number of cigarettes per day: $17.72{\pm}1.22$) participated in this study. All subjects completed a graded exercise testing to determine the relative exercise intensity. The cardiovascular responses were measured at rest, and during mild and moderate exercise immediately, 24, and 48 hours after smoking. The same procedures were repeated during 24-h smoking withdrawal. All subjects were continuously instrumented to measure systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (CO), and total vascular conductance (TVC) at rest and during exercise. The results showed that compared to the nicotine abstention, SBP, DBP, MAP, and HR were significantly higher at 24 and 48 hours after smoking ($p$<0.05), and CO was significantly higher at rest and during moderate exercise ($p$<0.05). There were no differences in SV and TVC before and after smoking. Thus, the results suggest that smoking is associated with an exaggerated sympathetic nerve activity during dynamic exercise. Consequently, smoking cessation may help reduce cardiac events, such as stroke and heart attack, during exercise.