• The Korean Journal of Physiology and Pharmacology
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• 제5권3호
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• pp.253-258
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• 2001

The present study was aimed to examine whether the expression of renin is associated with that of cyclooxygenase-2 (COX-2) in the kidney. Male Sprague-Dawley rats were made two-kidney, one clip (2K1C) or deoxycorticosterone acetate (DOCA)-salt hypertensive, to stimulate or to inhibit the endogenous renin-angiotensin system, respectively. The expression of renin and COX-2 mRNA was determined in the cortex of the kidney by reverse transcription-polymerase chain reaction. 2K1C hypertensive rats showed an increased expression of renin as well as of COX-2 in the clipped kidney. The expression of renin was decreased in parallel with that of COX-2 in the contralateral non-clipped kidney. Removal of the renal arterial clip reversed the expression of both genes, along with the blood pressure, to the control level. On the other hand, DOCA-salt hypertension was associated with parallel decreases of renin and COX-2 expression. These results indicate that renin and COX-2 genes are coordinately expressed in the kidney.

• The Korean Journal of Physiology and Pharmacology
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• 제4권2호
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• pp.143-147
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• 2000

The present study was aimed at investigating whether there are changes in the expression of nitric oxide synthase (NOS) in relation with the unclipping-induced fall of blood pressure in two-kidney, one clip (2K1C) hypertension. Male Sprague-Dawley rats were made 2K1C hypertensive by clipping the left renal artery for four weeks. Sham-clipped rats served as control. The expression of endothelial constitutive (ec) NOS proteins and tissue levels of NO metabolites were determined in the kidney. Systolic blood pressure was significantly increased in clipped rats compared with that in the control. The development of hypertension was associated with decreases in the expression of ecNOS proteins and tissue levels of NO metabolites in the clipped kidney. The blood pressure at twenty-four hours after removal of the renal arterial clip fell to the control level. Accordingly, in the unclipped kidney, the expression of ecNOS proteins and tissue contents of NO metabolites were increased to the control level. The contralateral kidney was not affected by the development or reversal of hypertension. It is suggested that an enhanced expression of ecNOS in the unclipped kidney is an important component in the reversal of renovascular hypertension.

• The Korean Journal of Physiology and Pharmacology
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• 제2권4호
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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.

• Childhood Kidney Diseases
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• 제20권1호
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• pp.33-36
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• 2016

There are two pathogenic models of renovascular hypertension (RVH) originating from renal artery stenosis. We noted a case of a boy who had severe hypertension with atrophic left kidney, hypertrophic right kidney, a segmental stricture of the abdominal aorta, and total occlusion of the right renal artery. Due to the atrophic change of the contralateral, unclipped left kidney, this patient presented with various clinical manifestations related to both models of pathogenesis of RVH occurring at the same time. We conclude that this patient presented with the middle stage of the two RVH pathogenetic models, so called the 'one-clip, one and half-kidney model.'

• The Korean Journal of Physiology and Pharmacology
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• 제8권3호
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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.

• The Korean Journal of Physiology
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• 제23권1호
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• pp.43-49
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• 1989

Atrial natriuretic peptide (ANP)의 혈압조절에 대한 효과를 구명하기 위하여 2-kidney, 1-clip 흰쥐의 고혈압 발생에 미치는 ANP의 영향을 조사하였다. 실험군은 왼쪽 신동맥에 clip을 끼우고 경정맥내에 지속적으로 ANP를 주입한(atriopeptin III, 500 ng/h) 군으로 하였으며, 대조군은 clip을 끼웠으나 ANP를 주입하지 않은 군으로 하였다. Clip을 끼우기 전과 clip을 끼운 제 4,7,10일에 꼬리동맥으로부터 혈압을 측정한 후 단두하여 혈액을 채취하고 양측 신장을 떼어내어 renin 치를 구하였다. ANP 주입군은 대조군에 비하여 고혈압의 발생이 약화되었고 혈장 renin활성도가 유의하게 낮았으나 신피질 renin함량은 양군간에 유의한 차이가 없었다. 한편 clip을 끼우지 않은 흰쥐에서는 ANP 주입군과 비주입군간에 혈압, 혈장 renin 활성도와 신피질 renin 함량 등이 모두 서로 유의한 차이를 보이지 않았다. 이상의 실험결과는 지속적 ANP 주입이 2-K, 1-C 흰쥐의 고혈압 발생을 방지하지는 못하였으나 약화시켰음을 보여주었으며, ANP는 적어도 부분적으로는 renin-angiotensin계를 길항하므로써 장기적 혈압 조절에 관여하는 것이 시사되었다.

• The Korean Journal of Physiology
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• 제20권1호
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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.

• The Korean Journal of Physiology and Pharmacology
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• 제3권3호
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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.

• 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.

• The Korean Journal of Physiology and Pharmacology
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• 제4권1호
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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.