• The Korean Journal of Physiology and Pharmacology
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• v.1 no.5
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• pp.529-535
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• 1997

The present study was aimed at investigating whether the vascular calcium regulation is altered in hypertension. Two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertension were made in rats, and their thoracic aortae were taken 4 weeks later. The isometric contractile response and calcium uptake of the endothelium-denuded aortic preparations were determined. Caffeine ($0.1{\sim}35\;mmol/L$) induced a greater contraction in 2K1C and DOCA-salt hypertension than in normotensive control. When the vascular calcium store was functionally-depleted by a repeated exposure to caffeine, it took longer to reload the store and to resume the initial contraction force in response to caffeine in both 2K1C and DOCA-salt hypertension. The vascular $^{45}Ca$ uptake following the functional depletion of the cellular store was also greater in both models of hypertension than in control. Ryanodine, calcium channel activator of the sarcoplasmic reticulum, attenuated the restoration of caffeine-induced vascular contraction, which was not affected by either 2K1C or DOCA-salt hypertension. Nifedipine, an L-type $Ca^{2+}$ channel blocker, attenuated the restoration of caffeine-induced contraction, which was not affected by DOCA-salt hypertension, but was more pronounced in 2K1C hypertension. Nifedipine also diminished the vascular $^{45}Ca$ uptake, which was not affected by DOCA-salt hypertension, but was more pronounced in 2K1C hypertension. Ouabain, a $Na^+,\;K^+-ATPase$ inhibitor, increased the caffeine-induced contraction by a similar magnitude in control and 2K1C hypertension, which was, however, markedly attenuated in DOCA-salt hypertension. Ouabain enhanced the vascular $^{45}Ca$ uptake, the degree of which was not affected by 2K1C hypertension, but was markedly attenuated in DOCA-salt hypertension compared with that in control. Cyclopiazonic acid, a selective inhibitor of $Ca^{2+}-ATPase$ of the sarcoplasmic reticulum, attenuated the restoration of caffeine-induced contraction, which was not affected by 2K1C hypertension, but was more marked in DOCA-salt hypertension. These results suggest that the increased vascular calcium storage may be attributed to an enhanced calcium influx in 2K1C hypertension, and to an impaired $Na^+-K^+$ pump activity of the cell membrane and subsequently increased calcium pump activity of the cellular store in DOCA-salt hypertension.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.351-356
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• 1999

The present study was aimed at investigating whether the calcium current in the vascular smooth muscle (VSM) cells is altered in renal hypertension. Two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertension were made in Sprague-Dawley rats. Rats without clipping the renal artery or implanting DOCA were used as control for 2K1C and DOCA-salt hypertension, respectively. Four weeks after clipping, systolic blood pressure was significantly higher in 2K1C rats than in control $(192{\pm}24\;and\;119{\pm}4$ mmHg, respectively, n=16 each). DOCA-salt rats also showed a higher blood pressure $(180{\pm}15$ mmHg, n=18) compared with control $(121{\pm}6$ mmHg, n=14). VSM cells were enzymatically and mechanically isolated from basilar arteries. Single relaxed VSM cells measured $5{\sim}10\;{\mu}m$ in width and $70{\sim}150\;{\mu}m$ in length were obtained. VSM cells could not be differentiated in size and shape between hypertensive and normotensive rats under light microscopy. High-threshold (L-type) calcium currents were recorded using whole-cell patch clamp technique. The amplitude of the current recorded from VSM cells was larger in 2K1C hypertension than in control. Neither the voltage-dependence of the calcium current nor the cell capacitance was significantly affected by 2K1C hypertension. By contrast, the amplitude of the calcium current was not altered in DOCA-salt hypertension. These results suggest that high-threshold calcium current of the VSM cells is altered in 2K1C hypertension, and that calcium channel may not be involved in calcium recruitment of VSM in DOCA-salt hypertension.

• Korean Journal of Acupuncture
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• v.19 no.1
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• pp.47-56
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• 2002

The frequency of the hypertension is increasing as the life level is improved and an average span of the life is extended since we approached modern stage. The hypertension is also dangerous disease which raises fatal complication for example with the bleeding aproplexy and the ischemic attack. The medicinal treatment about the hypertension is required patients to take continually. The acupuncture have been introduced because a medicine-chemical treatment hasn't good influence on the human body. It recently has been processed that studies acupuncture effect for blood pressure and have been found out that blood pressure go down. The object of this study observe the effect of LR3 acupuncture on hypertension in Renal Hypertension RAT induced by 2K1C. The 2K1C model was based on renin-angiotensin system. We put the silver clip in renal artery to induce renal hypertension. We try to observe that LR3 acupuncture influence on the blood pressure and c-fos expression in CVLM, NTS, RVLM. In results, the blood pressure was decreased during acupuncture than before acupuncture, after acupuncture. The heart rate was also decreased during acupuncture than before acupuncture, after acupuncture. The LR3 acupuncture significantly effects on blood pressure and heart rate (P<0.05). The increased expression of c-fos was shown in CVLM, NTS, but not in RVLM. In conclusion, LR3 was relived the action of control upon the hypertension and related with medulla, particularly CVLM, NTS. It needs to be closely examined pharmacological mechanism and studied combination with other acupoints.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.55-61
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• 2000

The present study was conducted to investigate the possible role of the sympathetic nervous system in two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertension. 2K1C and DOCA- salt hypertension were made in Sprague-Dawley rats. Four weeks after induction of hypertension, systolic blood pressure measured in conscious state was significantly higher in 2K1C $(216{\pm}18\;mmHg)$ and DOCA-salt $(205{\pm}29\;mmHg)$ groups than that in control $(128{\pm}4\;mmHg).$ The third branches (＜300 ${\mu}m$ in outer diameter) of the mesenteric artery were isolated and cut into ring segments of $2{\sim}3$ mm in length. Each ring segment was mounted in tissue bath and connected to a force displacement transducer for measurement of isometric tension. The arterial rings were contracted by application of norepinephrine (NE) in a dose-dependent manner. The amplitude of the NE-induced contraction of the vessels was significantly larger in hypertension than in control. The NE-induced contraction was significantly enhanced by neuropeptide Y (NPY) in hypertension. Reciprocally, NPY-elicited vasocontraction was increased by NE in hypertension. These results suggest that the sympathetic nervous system contributes to the development of 2K1C and DOCA-salt hypertension.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.4
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• pp.455-460
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• 1998

The present study was aimed at investigating whether the development of hypertension is related with an altered expression of nitric oxide synthases (NOS) in the kidney. By Western blot analysis, the expression of bNOS and ecNOS isoforms was determined in the kidney of deoxycorticosterone acetate (DOCA)-salt and two-kidney, one clip (2K1C) rats. In DOCA-salt hypertension, the expression of both bNOS and ecNOS was decreased, along with tissue contents of nitrites. In 2K1C hypertension, the nitrite content of the clipped kidney was decreased along with ecNOS levels, whereas neither the nitrite content nor the expression of NOS isoforms was significantly altered in the contralateral non-clipped kidney. These results suggest that the development of hypertension is associated with an altered renal expression of NOS and nitric oxide generation in DOCA-salt and 2K1C rats.

• Journal of Chest Surgery
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• v.32 no.2
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• pp.138-143
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• 1999

Background: The endothelium-dependent vasorelaxation has been largely accounted for by the release of nitric oxide (NO). Three distinct isoforms of NO synthases (NOS) have been characterized, i.e., brain(bNOS), inducible (iNOS), and endothelial constitutive (ecNOS). Although hypertension hasbeen associated with a vascular endothelial dysfunction, changes in the vascular expression of NOS isoforms have not been established. The present study was aimed at exploring the vascular expression of NOS isozymes in hypertension. Material and Method: Two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertension were induced in rats. The expression of different NOS isozymes in the thoracic aorta was determined by Western blot analysis. The vascular tissue contents of nitrites were measured by colorimetric assay. Result: Arterial blood pressure was significantly higher in experimental groups of 2K1C and DOCA-salt rats compared with their corresponding control rats. The vascular expression of bNOS as well as that of ecNOS was decreased in both models of hypertension. iNOS was not changed in DOCA-salt hypertension, but was also decreased in 2K1C hypertension. The vascular contents of nitrites were significantly decreased in DOCA-salt as well as in 2K1C hypertension. Conclusion: These results suggest that 2K1C and DOCA-salt hypertension are associated with decreases in the vascular expression of NOS isozymes and nitrite contents.

• Journal of Preventive Medicine and Public Health
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• v.31 no.1 s.60
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• pp.59-71
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• 1998

To examine the association of hypertension with cluster of obesity, abnormal glucose and dyslipidemia in Korean urban population, we conducted this cross-sectional study among 3027 men and 2127 women age 20-85 years who visited a prevention center between May 1991 and June 1995 for a multiphasic health check at St. Mary's Hospital, Seoul. By the self-administered questionnaire, the informations of educational attainments, monthly income, alcohol consumption, cigarette smoking, and physical excercise level were obtained. Height, weight, and blood pressure were measured by a trained nurse. The fasting blood sugar (FBS), total cholesterol, high density lipoprotein (HDL) cholesterol and triglyceride were tested by enzyme method. Low density lipoprotein (LDL) cholesterol was calculated by 'total cholesterol - HDL cholesterol - triglyceride/5'. For testing the differences of cardiovascular risk factors between hypertension and normotension group, 1-test and $\chi^2$-test were performed. For the age adjusted odds ratios of hypertension in persons with obesity, abnormal glucose, and dyslipidemia compared with normal, logistic regression was performed by using SAS pakageprograme. The results obtained were as follows: 1. Age, weight, body mass index(BMI), blood glucose, total cholesterol, LDL cholesterol, and triglyceride of hypertension group in men and women were significantly higher than normotension group, but height and HDL cholesterol of hypertension group only in women significantly lower than normotension group. The frequency of obesity $(BMI\geq25kg/m^2)$, abnormal glucose $(\geq\;120mg/dl)$, hypercholesterolemia $(\geq\;240mg/dl)$, lower HDL cholesterol (<45 mg/dl in women only), higher LDL cholesterol $(\geq\;160mg/dl)$, and hyper hypertriglyceridemia $(\geq\;250mg/dl)$ in hypertension group of men and women were significantly higher than normotension group. 2. Systolic and diastolic blood pressure were negatively correlated with hight, but positively with age, weight, BMI, total cholesterol, LDL cholesterol, and triglyceride in men and women. BMI was positively correlated with fasting blood sugar, total cholesterol, LDL cholesterol and triglyceride but negatively with HDL cholesterol. 3. The age adjusted odds ratios of hypertension were as follows in men and women : among persons who were obese compared with those nonobese, 2.53 (95% Confidence Intervals [C.I.] 2.08-3.07) and 2.22 (95%C.I. 1.71-2.87): among persons who were abnormal glucose compared with those normoglycemic, 1.43 (95%C.I 1.13-1.82) and 2.01 (95%C.I 1.36-2.94): and among persons who were dyslipidemia (hypercholesterolemia or lower HDL cholesterol or higher LDL cholesterol or hypertriglyceridemia) compared with those normal lipid, 1.59 (95%C.I 1.30-1.95) and 1.51 (95%C.I 1.16-1.96). After combined more than one risk factor, the odds ratios were increased. Among persons with cluster of obesity, abnormal glucose, and dyslipidemia, the odds ratio of hypertension was 2.25 (95%C.I 1.47-3.37) in men and 3.02 (95%C.I 1.71-5.30) in women. In conclusion, it was suggested that hypertension was associated with cluster of obesity, abnormal glucose, dyslipidemia in this Korean urban population.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.3
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• pp.147-151
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• 2004

The present study was undertaken to determine the regulation of heat shock proteins (HSP) in the kidney in hypertension. Two-kidney, one clip (2K1C) or deoxycorticosterone acetate (DOCA)-salt hypertension was induced in male Sprague-Dawley rats. At weeks 1 and 4 after inducing the hypertension, the expression of HSP70, HSP32 and HSP25 was determined in the kidney by Western blot analysis. In 2K1C hypertension, the expression of HSP70, HSP32 and HSP25 was increased in the clipped kidney at both weeks 1 and 4. However, in the contralateral kidney, their expression was not significantly altered at week 1, but increased at week 4. In DOCA-salt hypertension, the expression of HSP remained unaltered in the remnant kidney at week 1, but significantly increased at week 4. These results indicate that HSP are differentially regulated in the kidney according to the duration and the model of hypertension.

• Journal of Preventive Medicine and Public Health
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• v.38 no.3
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• pp.325-329
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• 2005

Objectives : This study was performed to assess the association between high sensitivity C-Reactive Protein (hsCRP) and hypertension. Methods : We evaluated the relationship between hsCRP with hypertension and other cardiovascular risk factors, using a cross-sectional survey of 202 people over the age of 50, living in a rural area. A logistic regression analysis was used to study the association between hsCRP and hypertension. The hsCRP levels were divided in quartiles, and the odds ratios (OR), with 95% confidence intervals (95% CI), calculated, using the lowest quartile as a reference. Results : The subjects consisted of 37.1% men and 62.9% women, with a mean (SD) hsCRP level of $1.9({\pm}3.0mg/{\ell})$ . The overall prevalence of hypertension was 61.4%. The prevalence of hypertension according to the hsCRP quartile was not statistically significant. After adjustment for confounding variables, the prevalence of hypertension according to the subjects in the 2nd, 3rd and 4th hsCRP quartiles were 1.418 (95% CI=0.554-3.628), 1.124 (95% CI=0.392-3.214) and 0.892 (95% CI=0.312-2.547) times higher, respectively, compared to those in the 1st quartile. Conclusions : The results showed that the level of hsCRP was not a risk factor for hypertension among adults aged over 50 years, living in a rural area. A further study should be performed to find the association between hsCRP and hypertension.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.89-102
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• 1986

It has long been suggested that the change of renin-angiotensin system is responsible for the increased arterial blood pressure in the experimental hypertension. But the exact nature of the cause and maintenance of early and late Phase of renal hypertension is still controversial. Increased renin-angiotensin system has been suggested. To clarify the altered renin-angiotensin system in the early phase of two kidney one clip Goldblatt hypertension(2K1C GH), experiments were carried out in the rats of 3,7, and 14 days of 2K1C GH rats, sham-operated, and control rats. Responses of the plasma renin activity to the intravenous infusion of L-isoproterenol were dose-dependent. Responses of the plasma renin activity to the intravenous L-isoproterenol in 2K1C GH rats were not different from sham-operated control rats. Hypotensive responses of the 2K1C GH rats were not different from sham-operated rats. Suppression by intravenous infusion of angiotensin II of plasma renin activity showed a dose-dependent manner. Suppression by angiotensin ll of plasma renin activity was attenuated or abolished in the early phase of 2K1C GH rats. Intravenous infusion of arginine vasopressin(AVP) showed a dose-dependent suppression of plasma renin activity, Attenuated responses by AVP of plasma renin activity were noticed in the early phase of 2K1C GH rats. These results suggest that the altered renin-angiotensin system in the early phase of the two kidney one clip Goldblatt hypertension may be caused by failure of the short loop negative feedback control mechanism.