• The Korean Journal of Physiology and Pharmacology
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• 제3권5호
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• pp.471-479
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• 1999

The Kv channel activity in vascular smooth muscle cell plays an important role in the regulation of membrane potential and blood vessel tone. It was postulated that increased blood vessel tone in hypertension was associated with alteration of Kv channel and membrane potential. Therefore, using whole cell mode of patch-clamp technique, the membrane potential and the 4-AP-sensitive Kv current in cerebral arterial smooth muscle cells were compared between normotensive rat and one-kidney, one-clip Goldblatt hypertensive rat (lK,lC-GBH rat). Cell capacitance of hypertensive rat was similar to that of normotensive rat. Cell capacitance of normotensive rat and 1K,lC-GBH rat were $20.8{\pm}2.3$ and $19.5{\pm}1.4$ pF, respectively. The resting membrane potentials measured in current clamp mode from normotensive rat and 1K,lC-GBH rat were $-45.9{\pm}1.7$ and $-38.5{\pm}1.6$ mV, respectively. 4-AP (5 mM) caused the resting membrane potential hypopolarize but charybdotoxin $(0.1\;{\mu}M)$ did not cause any change of membrane potential. Component of 4-AP-sensitive Kv current was smaller in 1K,lC-GBH rat than in normotensive rat. The voltage dependence of steady-state activation and inactivation of Kv channel determined by using double-pulse protocol showed no significant difference. These results suggest that 4-AP-sensitive Kv channels playa major role in the regulation of membrane potential in cerebral arterial smooth muscle cells and alterations of 4-AP-sensitive Kv channels would contribute to hypopolarization of membrane potential in 1K,lC-GBH rat.

• Korean Journal of Acupuncture
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• 제24권3호
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• pp.165-177
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• 2007

Objectives : The purpose of this study was to examine effects of acupuncture by needle manipulation at $LR1{\cdot}Kl1$ on the blood pressure, plasma levels of ANP(atrial natriuretic peptide), renin and cardiomegalic index in hypertensive rat Induced by two kidney one clip(2K1C). Material and methods : The groups divided into 7 groups; Control, no treatment. Acu-1,acupuncture at $LR1{\cdot}Kl1$ bilaterally and the needle was twirled and rotated forward with the thumb of the right hand 6 times. Acu-2, acupuncture at $LR1{\cdot}Kl1$ bilaterally and the needle was twirled and rotated forward with the forefinger of the right hand 6 times. Acu-3, acupuncture at $LR1{\cdot}Kl1$ bilaterally and the needle was inserted in the opposite direction(body direction) as the channel runs, Acu-4, acupuncture at $LR1{\cdot}Kl1$ bilaterally, the needle was inserted in the opposite direction(body direction) as the channel runs and the needle was twirled and rotated forward with the forefinger of the right hand 6 times. The acupuncture executed 5times for 2 weeks. Results : Systolic blood pressure was decreased significantly in Acu-2, Acu-3 and Acu-4. Plasma renin was decreased significantly in Acu-2 and Acu-4. Plasma ANP was increased significantly in Acu-2, however was decreased significantly in Acu-4. Cardiac hypertrophy index was decreased significantly in Acu-1, Acu-2, Acu-3 and Acu-4. Conclusions : These results suggest that acupuncture by needle manipulation at $LR1{\cdot}Kl1$ is effective in hypertension by renal blood problem.

• 동의생리병리학회지
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• 제30권2호
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• pp.95-100
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• 2016

The aim of the present study is to investigate the hypotensive effect of Mantidis ootheca (WMO), Rosa laevigata (WIC), and Imperata cylindrica (WRL) in renovascular hypertension rats. Experimental hypertension model is 2-kidney and 1-clip (2K1C) induced rats. 2K1C rats were treated with WMO, WIC, and WRL at dose of 100 mg/kg/day orally for 3 weeks, respectively. Treatment groups with WMO, WIC, and WRL significantly lowered blood pressure. Interestingly, WMO, WIC, and WRL ameliorated endothelium-dependent and independent vascular relaxation in the phenylephrine-precontracted thoracic aorta in hypertension models. In addition, 2K1C-induced hypertension model increased plasma renin activity, however, WMO, WIC, and WRL attenuated those activities. These results suggest that WMO, WIC, and WRL ameliorates vascular dysfunction in 2K1C-induced hypertension models via the regulation of nitric oxide and renin-angiotensin-aldosterone system.

• Journal of Chest Surgery
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• 제32권2호
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• pp.138-143
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• 1999

배경: 혈관 내피층에서 분비되어 평활근층 이완을 일으키는 물질의 본체는 산화질소(nitric oxide, NO)이며 NO synthase(NOS)에는 뇌형(brain NOS, bNOS), 내피세포형(endothelial constitutive NOS, ecNOS) 및 유도형 (inducible NOS, iNOS) 등 세 가지 동위효소가 있음이 알려져 있다. 고혈압은 혈관 내피층 기능 이상을 보임이 알려져 있으나 NOS 동위 효소의 변화를 포함한 세포내 기전은 아직 확실치 않다. 저자들은 고혈압 기전을 구명하기 위한 일환으로 고혈압 혈관에서 NOS 동위효소가 어떻게 변화되는가 조사하고자 하였다. 대상 및 방법: 흰쥐에서 two-kidney, one clip (2K1C) 고혈압과 deoxycorticosterone acetate(DOCA)-salt 고혈압을 일으켰다. 4주 뒤 고혈압이 일어난 것을 확인하고 적출 흉부 대동맥 표본에서 Western blot 분석에 의한 NOS 동위효소 발현 조사 및 비색법에 의한 조직내 산화질소 정량을 하였다. 결과: 2K1C 및 DOCA-salt 흰쥐에서 실험군은 각각의 대조군에 비해 유의하게 높은 혈압을 보였다. 두 고혈압군에서 모두 적출 대동맥 표본의 bNOS 및 ecNOS 단백 발현이 감소되었다. iNOS 단백은 DOCA-salt 고혈압에서 변화를 보이지 않으나 2K1C 고혈압에서는 역시 감소를 보였다. 혈관조직내 산화질소 함량은 두 고혈압에서 모두 유의하게 감소되었다. 결론: 2K1C 및 DOCA-salt 고혈압에서 혈관의 NOS 발현과 산화질소 함량이 감소되어 있으며 이는 고혈압의 유지 기전에 공헌하리라 추측되었다.

• The Korean Journal of Physiology
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• 제28권2호
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• pp.191-196
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• 1994

Captopril, an inhibitor of angiotensin converting enzyme, is also known to inhibit the degradation of bradykinin. We examined the effects of intracerebroventricular (ICV) captopril on the central pressor response to bradykinin in normotensive, 2-kidney, 1 clip Goldblatt (GHR) and deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Captopril (1 mg) and bradykinin (5 nmol) were administered into the right lateral cerebral ventricle, and blood pressure and heart rate were continuously monitored throughout the experiment. ICV captopril alone did not affect the blood pressure within 10 minutes but it significantly augmented the central pressor response to bradykinin in GHR. On the contrary, captopril was without effect on the pressor response to bradykinin in normotensive and DOCA-salt rats. These findings indicate that endogenous kinins are not critical in regulating arterial pressure in normotensive and DOCA hypertensive rats. However, in GHR, an enhanced activity of the brain kallikrein-kinin system in maintaining the high blood pressure is suggested.

• Journal of Ginseng Research
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• 제23권2호
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• pp.81-87
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• 1999

신성고혈압백서모델인 one-kidney, one-clip Goldblatt 고혈압백서에서 혈압과 NO생성에 미치는 고려홍삼 사포닌과 비사포닌의 영향을 규명하고자, 무마취 무제한상태에서 혈압을 측정하고, 혈중 NO와 NO합성효노에 대한 활성 및 단백량을 실시한 결과이다. 고려홍삼 사포닌은 정상혈압백서 및 신성고혈압백서에서 모두 혈압을 강하시키는 효과가 현저하였는데 혈압강하는 초기 2-4분 동안 최대를 보였으며 혈압강하와 동시에 심박수의 증가 현상이 관찰되었다. 그러나 고려홍삼 비사포닌은 혈압강하효과와 심박수의 증가현상은 사포닌에 비하여 미미 하였다. 고려홍삼 사포닌에 의한 혈압강하 현상과 NO와의 상관관계를 규명하기 위하여 혈중 NO를 측정한 결과 홍삼사포닌은 혈중 NO를 상승시켰다. NO합성효소의 활성도를 측정하기 위하여 $[^{3}H]-L-arginine$의 $[^{3}H]-L-cioulline$으로의 변환률을 측정한 결과 고려홍삼 사포닌에 의하여 NO합성효소의 활성도는 증가하였다. 이상의 결과를 종합해 볼 때 고려홍삼은 혈압을 강하시키는 효과가 있으며, 이러한 혈압강하는 주로 사포닌 성분에 의한 것으로 생각된다. 이러한 고려홍삼 혈압강하 현상은 혈중의 NO량을 증가시키는 것에 기인하며 NO의 증가는 NO합성효소의 활성도의 증가에 기인하는것으로 사료된다.

• Journal of Acupuncture Research
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• 제20권6호
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• pp.1-12
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• 2003

Objective : The aim of this experiments was to investigate the effects of Kyongo Puryu(originated from ${\ll}$Classic on Difficulty${\gg}$), Kyongo Um-gok(originated from ${\ll}$Ling Shu${\gg}$) acupuncture on the Blood Pressure, Cardiomegalic index, and plasma levels of atrial natriuretic peptide in Hypertensive RAT induced by 2K1C. Methods : The effects of Kyongo(L8) Puryu(K7), Kyongo(L8) Um-gok(K10) acupuncture on Blood Pressure in Hypertensive RAT induced by Two Kidney One Clip(2K1C). Results : I. Blood Pressure was decreased significantly after acupuncture of L8 K7. II. Cardiomegalic index decreased significantly after acupuncture of L8 Puryu, L8 K10. IlI. Plasma levels of atrial natriuretic peptide was increased significantly after acupuncture of L8 K7.

• The Korean Journal of Physiology and Pharmacology
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• 제5권1호
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• pp.65-70
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• 2001

The present study was aimed to explore pathophysiological implications of nitric oxide in the development of left and right ventricular hypertrophy. To induce selective left and right ventricular hypertrophy, rats were made two-kidney, one clip (2K1C) hypertensive and treated with monocrotaline (MCT), respectively. Six weeks later, the hearts were taken and their ventricular tissue mRNA and protein expression of endothelial constitutive isoform of nitric oxide synthase (NOS) were determined by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. In 2K1C hypertensive rats, the expression of NOS mRNA was increased in parallel with its proteins in the left ventricle, but not in the right ventricle. In MCT-treated rats, the expression of NOS mRNA and proteins were proportionally increased in the right ventricle, but not in the left ventricle. These results suggest that the expression of NOS is specifically increased in association with the ventricular hypertrophy, which may be a mechanism counteracting the hypertrophy.

• Journal of Acupuncture Research
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• 제20권1호
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• pp.1-12
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• 2003

Objectives : The purpose of this study is to compare Xingjian(LR2) Shaofu(HT8) with Dadun(LR1) Shaofu(HT8) on Blood Pressure in Hypertensive RAT induced by Two Kidney One Clip(2KIC). Methods : This experiments was to investigate the effects of LR2 HT8(originated from ${\ll}$Classic on Difficulty${\gg}$ Shi Ze Xie Qi Zi), LR1 HT8(originated from ${\ll}$Ling Shu${\gg}$ Sheng Ze Xie Zhi) acupuncture on the blood pressure, cardiomegalic index, and plasma levels of atrial natriuretic peptide in hypertensive rat induced by 2K1C. Results: 1. Blood pressure was decreased significantly after third acupuncture of LR2 HT8. 2. Blood pressure was decreased significantly after acupuncture of LR2 HT8, but was increased after LR2 HT8. 3. Cardiomegalic index was not changed after acupuncture of LR2-HT8 and LR1-HT8 4. Plasma levels of atrial natriuretic peptide was increased significantly after acupuncture of LR2 HT8 but LR1 HT8 was not changed.

• 대한약리학회지
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• 제23권2호
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• pp.123-131
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• 1987

Morphine을 비롯한 opioid peptide가 말초 또는 중추에 투여시 혈압하강과 심박동수감소를 보이며 opiate 수용체 길항제인 naloxone에 의해 길항됨이 관찰되었던바 근래 몇몇 보고들은 중추신경내에서 adrenergic및 opioidergic system이 서로 관련되어 있음을 시사하고 있다. 이에 본 실험에서 고혈압 연구에 널리 사용되고 있는 2-kidney, 1-clip (2K1C) 방법으로 실험적 고혈압을 유발시킨 백서의 측뇌실내 clonidine또는 morphine의 심맥관계에 대한 효과와 각각의 차단제에 의한 영향 그리고 정상 및 고혈압상태 백서의 뇌내 ${\beta}-endorphin$의 함량과 specific opiate receptor binding을 정량하여 고혈압 유발에 따른 뇌내 opiate system의 변동을 관찰하였다. 2K1C 고혈압 또는 sham-operated대조백서에서 측뇌실내 clonidine $(3-30\;{\mu}g/kg)$은 용량에 비례하여 혈압하강과 심박동수감소를 일으켰으며 clonidine의 혈압강하 효과는 2K1C고혈압 백서에서 더욱 현저하였다. clonidine의 혈압강하효과는 고혈압 백서에서 측뇌실내 yohimbine 또는 naloxone 전처리에 의해 약화되었고 대조군에서는 yohimbine ($30\;{\mu}g/kg$, i.v.t.)에 의해 억제되었으나 naloxone ($50\;{\mu}g/kg$, i.v.t.)에 의해서는 영향 받지 않았다. clonidine과 마찬가지로 측뇌실내 morphine $(10-100\;{\mu}g/kg)$은 2K1C 고혈압 또는 sham-operated 대조백서에서 용량에 비례하여 혈압하강과 심박동수감소를 일으켰으며, morphine의 혈압강하효과는 2K1C 고혈압백서에서 더욱 현저하였다. 대조군과 고혈압군에서 morphine의 혈압강하효과는 naloxone 전처리에 의해 현저히 약화되었으나 yohimbine에 의해서는 영향 받지 않았다. 2K1C 시술익일부터 투여한 clonidine은 2K1C 시술에 의한 혈압 상승을 억제하였으며 naloxone (2 mg/kg, i.p.)에 의해 반전되었다. 2K1C 시술에 의해 고혈압이 유발된 백서의 뇌내 ${\beta}-endorphin$ 함량은 sham-operated 군에 비하여 유의하게 감소되어 있었고 (3H)-naloxone의 specific binding의 Bmax는 증가되었으나 Kd치는 변동되지 않았다. 이상의 실험 성적은 뇌내 opiate계가 혈압조절에 중요한 역할을 담당하고 있으며 2K1C 고혈압백서의 고혈압상태 유지에 뇌내 opiate계의 기능저하가 일부관여하고 있음을 강력히 시사한다.