• Bulletin of the Korean Chemical Society
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• 제23권3호
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• pp.395-399
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• 2002

The voltammetric behavior of spontaneously adsorbing Mo layers on Pt(111) and Pt(100) electrodes has been studied to estimate the number of electrons involved in the electrochemical processes of spontaneously adsorbed Mo and the number of the bloc ked Pt sites for hydrogen adsorption. On Pt(111) and Pt(100) surfaces, the spontaneously adsorbed Mo layers showed redox peaks at 0.10 V and 0.15 V, respectively, and continuous current-potential waves in the conventional hydrogen region. Since the potential range of the Mo redox processes on both surfaces overlapped partially with the potential range of hydrogen adsorption, the variation in the ratio of the total charge of Mo and H ($Q_H$ +$Q_{MO}$) to the hydrogen charge of clean Pt electrode ($Q_H^0$) was analyzed. From the analysis, six electrons were estimated to be involved in the electrochemical processes of the spontaneously adsorbed Mo, and four Pt sites for hydrogen adsorption were calculated to be blocked by one adsorbed Mo atom. Based on these figures and the pH dependence of the Mo redox processes, we have proposed an electrochemical equation for the spontaneously adsorbed Mo. This electrochemical equation led us to conclude that the saturation coverage of the spontaneously adsorbed Mo is 0.25. The coverage of Mo less than 0.25, however, could not be determined voltammetrically due to the convolution of the charges of Mo and H.

• 대한한방내과학회지
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• 제31권1호
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• pp.142-152
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• 2010

Objective : This study was done to investigate the effect of Gamioknyeo-jeon (GOJ) on spontaneously hypertensive rats. Methods : Spontaneously hypertensive rats were sensitized and challenged with GOJ for 4 weeks. the experimental group was treated with 56.7mg/kg/day of GOJ orally while the control group was treated with 56.7mg/kg/day of normal saline instead. Results : 1. GOJ significantly showed safety against cytotoxicity and toxicity in the liver. 2. GOJ significantly decreased the heart rate and the blood pressure in Spontaneously hypertensive rats. 3. GOJ significantly decreased the levels of aldosterone in Spontaneously hypertensive rats. 4. GOJ significantly decreased the levels of dopamine and norepinephrine in Spontaneously hypertensive rats. 5. GOJ significantly decreased the levels of potassium and chloride in Spontaneously hypertensive rats. 6. GOJ significantly decreased the levels of uric acid, BUN and creatinine in Spontaneously hypertensive rats. Conclusion : These results suggest that GOJ might be useful in treatment of hypertension.

• 음성과학
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• 제9권3호
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• pp.99-112
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• 2002

The purpose of the present study was to investigate the effectiveness of self-monitoring on spontaneously initiating speech behavior of the hearing-impaired preschoolers. Three hearing-impaired preschoolers were selected from a special school for the deaf. They showed some vocalizations and words under intensive instruction settings, but never spontaneously spoke as a means of communication. Multiple probe design was applied in this study. During the self-monitoring intervention, each child was trained to assess whether his own initiating speech behavior was occurred or not, and then record his own behavior's occurrence on the self-recording sheets and self-graphing sheets. The vibration of handphone was used as a tactile cue for self-monitoring. The results of the present study were as follows: (1) self-monitoring significantly increased the percentage of occurrence of spontaneously initiating speech behaviors. (2) Increased level of spontaneously initiating speech behavior were generalized into another natural instruction (cognitive) settings. (3) Increased level of spontaneously initiating speech behavior were maintained after four weeks from the termination of the intervention.

• 생약학회지
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• 제24권3호
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• pp.255-257
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• 1993

We investigated the effects of single administration of Korean earthworm(Lamnodrilus gotai Hatai) juice (KEJ) on blood pressure and spontaneous motor activity in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats. We report that KEJ lowered blood pressure and spontaneous motor activity in SHR.

• The Korean Journal of Physiology
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• 제19권2호
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• pp.189-202
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• 1985

Enhanced activity of renin-angiotensin-aldosterone system has been suggested as a cause of the high blood pressure in certain forms of experimental hypertension. In spontaneously hypertensive rats, however, increased activity of the system has not been found, and even suppressed renin angiotensin system has been reported in the spontaneously hypertensive rat. In the present experiments it was attempted to explore the possible alteration of the short loop negative feedback control in the hypertensive rat. Experiments have been done in the anesthetized spontaneously hypertensive rats(SHR) as well as in normotensive Wistar and Sprague Dawley rats as control. Responses of the plasma renin activity to the intravenous L-isoproterenol were dose dependent, in both SHR and normotensive control rats. Hypotensive responses to smaller do sea of L-isoproterenol were more accentuated in SHR than in the normotensive control rats. Angiotensin If given intravenously suppressed plasma renin activity in a dose dependent fashion in both groups. However, these suppressive responses were significantly attenuated in SHR as compared with the normotensive control rats. Treatment with angiotensin I-converting enzyme inhibitor did not correct the attenuated responses of the plasma renin activity to angiotensin II in SHR. Intravenous infusion of arginine vasopressin also produced a dose-dependent suppression of plasma renin activity in both groups. The responses to arginine vasopressin were also significantly attenuated to the normotensive control rats. In the sodium-depleted SHR, arginine vasopressin did not suppress plasma renin activity, whereas the suppressive responses to arginine vasopressin in the normotensive control rats were not different from the untreated control rats. These data suggest that there may be a derangement in the short loop negative feedback control of the renin-angiotensin system in spontaneously hypertensive rat.

• Journal of Acupuncture Research
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• 제21권4호
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• pp.1-18
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• 2004

Objective : This study was performed to investigate the effects of aqua-acupuncture of Jibaikjihwangtang in two-kidney one clip Goldblatt hypertensive rats and spontaneously hypertensive rats. Methods : we injected aqua-acupuncture solution into Shin-Soo ($BL_{23}$) which corresponds to human acupuncture point in two-kidney one clip Goldblatt hypertensive rats and spontaneously hypertensive rats. Systolic blood pressure, renin activity, aldosterone and atrial natriuretic peptide (ANP) plasma levels were tested. Results : Systolic blood pressure decreased significantly after aqua-acupuncture of jibaikjihwangtang. Acupuncture group in two-kidney one clip Goldblatt hyper-tensive rats had deference with control group. In plasma levels of atrial natriuretic peptide, acupuncture group of spontaneously hypertensive rats increased meaningfully but to two-kidney one clip Goldblatt hypertensive rats it was decreased meaningfully. In Serum Aldosterone density, the acupuncture group of spontaneously hypertensive rats had significant alteration than control group, but the acupuncture group of two-kidney one clip Goldblatt hypertensive rats had decreased alteration than control group. Conclusion : According to these results, after Aqua-Acupuncture of Jibaikjihwangtang blood pressure decreased significantly and data suggest that blood pressure reduction activity connected with renin activity reduction in renal hypertensive rat.

• 대한한의학회지
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• 제19권2호
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• pp.50-58
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• 1998

The effects of the Evodiae fructus on the cardiovascular function were assessed in spontaneously hypertensive rats, and isolated preparation of spontaneously hypertensive rats aortic strip. In spontaneously hypertensive rats, intraperitoneal administration of methanol crude extract of Evodiae Fructus (0.5mg/kg) lowered aterial blood pressure which lasted for at least 4 hours. The hypotensive effect of Evodiae Fructus was more stronger with ${\alpha}-adrenoreceptor$ inhibitor(Phentholamine) and it was not affected by ${\beta}-adrenoreceptor$ inhibitor(Propranolol). The hypotensive effect of Evodiae Fructus was abolished by NAME. It is suggested that the hypotensive effect of Evodiae Fructus may be concern with endothelium-derived relaxing factor and it may be mediated through NO synthesis. Evodiae Fructus showed a vasorelaxing effect on denude aortic strip. It is suggested that Evodiae Fructus has a direct relaxing effect on vascular smooth muscle cells. Judging from above results, it was proved that hypotensive effect of Evodiae Fructus. The mechanism of hypotensive action may be concern with endothelium-derived relaxing factor and direct relaxing effect on vascular smooth muscle cells. Therefore, it is suggested that Evodiae Fructus is applicable to hypertension.

• The Korean Journal of Physiology
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• 제22권1호
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• pp.41-53
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• 1988

The present study was undertaken to clarify the involvement of atrial natriuretic peptide in the development of hypertension in spontaneously hypertensive rats. Plasma concentration of immunoreactive atrial natriuretic peptide was higher in spontaneously hypertensive rats than in normotensive Sprague-Dawley and Wistar rats. Plasma renin concentration was lower in SHR than in normotensive rats, as observed in earlier experiments. Hydration-induced increase in urine flow and urinary excretions of sodium and potassium were smaller in SHR than in normotensive control rats. Intraarterial infusion of atrial natriuretic peptide resulted in increases in urine flow, urinary excretions of sodium and potassium in both hypertensive and normotensive rats. Renal response to atrial natriuretic peptide was markedly suppressed in SHR. Plasma renin and aldosterone concentration were suppressed by atrial natriuretic peptide in both SHR and normotensive rats. The responses were not significantly different in both groups. These results suggest that the renal responsiveness to atrial natriuretic peptide may be suppressed in SHR by some mechanisms still remaining obscure.

• 생약학회지
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• 제30권2호
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• pp.226-230
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• 1999

We have isolated a sesquiterpene lactone, cumambrin A from the dried flowers of Chrysanthemum boreale Makino and reported its chemical structure. The aim of the present study was to investigate whether the exogenous administration of cumambrin A has a pharmacological effect on normalization of blood pressure in the spontaneously hypertensive rats (SHR). In vitro studies: Relaxative response induced by cumainbrin A was increased with dose-dependent manner and showed maximizing response at a concentration of $5{\times}10^{-4}M$. Further, this relaxative response was significantly increased at a condition of endothelium present than that of endothelium denuded. In vivo studies: The normalizing effect of cumambrin A on blood pressure was also increased with time-dependent manner and then gradually recovered to normal condition at approximately 4 hrs after cumambrin A treatment.

• Journal of Nutrition and Health
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• 제37권7호
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• pp.509-514
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• 2004

This study was conducted to investigate the supplementary effects of Lentinus edodes on blood pressure and blood lipid levels in the Hypertensive Rat. We supplied 3 kinds of experimental diets (Control; CO, cap of Lentinus edodes; LC, and stipe of Lentinus edodes; LS) to spontaneously hypertensive rats (SHR) for 8 weeks. Diet intake, body weight, organ weights, and serum lipid levels were measured. There was no significant difference in diet intake, and body, liver and epididymal fat pad weights among experimental groups. The levels of systolic and diastolic blood pressure were significantly lower in LC and LS groups than CO group. The concentrations of serum total cholesterol were lower in LC and LS groups than CO group. These results suggested that Lentinus edodes decrease blood pressure levels and serum total cholesterol concentration in the spontaneously hypertensive rats. But these effects of Lentinus edodes didn't show any significant difference between animals fed cap and stipe of this mushroom.