• 한국축산식품학회지
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• 제30권4호
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• pp.545-550
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• 2010

The effects of casein hydrolysate on blood pressure (BP) and serum lipid profiles were investigated in spontaneously hypertensive rats (SHR). Twenty-four 6-wk old male SHRs were assigned to 3 groups in a completely randomized design. Experimental groups were as follow: control, market milk group (MLG) and casein hydrolysate group (CHG). Reference blood pressure (RBP) showed average $198.94{\pm}1.46mmHg$. Blood pressure (BP) of CHG reduced 24 mmHg after 2 wk of treatment, but these increased after 3 wk. BP of CHG was significantly lower than BP of Control in experimental time (p<0.05). Serum lipid profiles were not differ significantly among groups (p<0.05). These data suggest that casein hydrolysate may beneficially improvement of blood pressure level in SHR.

• 대한수의학회지
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• 제44권1호
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• pp.7-13
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• 2004

Severe hypertension (>180 mmHg) develops in spontaneously hypertensive rats (SHR) after 12 wk-old; however, it is not clear whether what kinds of molecular mechanism leads to altered cardiac performance following developmental stages in SHR. Also, although the effect of calcineurin (Cn) to promote cardiomyocyte hypertrophy in vivo and in vitro is established, its overall necessity as a hypertrophic mediator is currently an area of ongoing debate. Thus, we have examined i) body weight and blood pressure, ii) differences of expression and distribution of signaling molecules such as Cn, protein kinase B/Akt (PKB/Akt), and extracellular signal-regulated kinase (ERK) between SHR and their age-matched control Wistar-Kyoto (WKY) rats following developmental stages. In 16 wk-old SHR compared with WKY, 2-dimentional echocardiography showed cardiac enlargement and hypertrophy of left ventricle, significantly. Taken together, we suggest that Cn is associated with hereditary cardiac hypertrophy, the process being related to the molecular signaling mechanisms involving PKB/Akt and ERK.

• The Korean Journal of Physiology and Pharmacology
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• 제20권6호
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• pp.621-628
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• 2016

Hypertension can be caused by various factors while the predominant causes include increase in body fluid volume and resistance in the circulatory system that elevate the blood pressure. Consumption of probiotics has been proven to attenuate hypertension; however, the effect is much strain-dependent. In this study, a newly isolated Lactobacillus casei (Lb. casei ) strain C1 was investigated for its antihypertensive properties in spontaneously hypertensive rats (SHR). Lactic acid bacteria (LAB) suspension of 11 log colony-forming unit (CFU) was given to SHR (SHR+LAB, n=8), and phosphate buffer saline (PBS) was given as a control in SHR (SHR, n=8) and in Wistar rats as sham (WIS, n=8). The treatment was given via oral gavage for 8 weeks. The results showed that the weekly systolic blood pressure (SBP), mean arterial pressure (MAP), diastolic blood pressure (DBP) and aortic reactivity function were remarkably improved after 8 weeks of bacterial administration in SHR+LAB. These effects were mostly attributed by restoration of wall tension and tensile stress following the bacterial treatment. Although not statistically significant, the level of malondialdehye (MDA) in SHR+LAB serum was found declining. Increased levels of glutathione (GSH) and nitric oxide (NO) in SHR+LAB serum suggested that the bacterium exerted vascular protection through antioxidative functions and relatively high NO level that induced vasodilation. Collectively, Lb. casei strain C1 is a promising alternative for hypertension improvement.

• The Korean Journal of Physiology
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• 제30권1호
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• pp.11-20
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• 1996

To investigate the properties of cromakalim-opened $K^{+}\;channels$ in aorta of spontaneously hypertensive rats (SHR), the effect of cromakalim on tension was compared in endothelium-rubbed aortic rings from SHR and normotensive Wistar-Kyoto rats (WKY). 1. Cromakalim relaxed the aortic ring contracted by $10^{-7}$ M norepinephrine (NE) dose-dependently, and this relaxant response to cromakalim was blocked by $10^{-5}$ M glybenclamide. 2. Cromakalim also relaxed the contraction induced by high $K^{+}$-solution or 10 mM tetraethylammonium dose-dependently. However, the relaxant response to cromakalim was decreased by raising the $K^{+}$ concentration. 3. SHR aorta exhibited myogenic tone in resting state which was inhibited by cromakalim, verapamil or $Ca^{2+}-free\;PSS.$ Whereas, WKY aorta did not exhibit any myogenic tone in resting state. 4. When aortic rings from both strains were contracted by $20\;mM\;K^{+}\;or\;NE$, relaxant responses to low concentration of cromakalim $(below\;10^{-7}\;M)$ were not different between WKY and SHR, but maximum relaxant response to cromakalim $(above\;3{\times}10^{-7} \;M)$ was greater in SHR than in WKY. 5. When the relaxant response to cromakalim was expressed as percent of maximum relaxation induced by $Ca^{2+}-free\;PSS$, relaxant response to cromakalim in 20 mM $K^{+}-induced$ contraction was not different between WKY and SHR. From the above result, it is suggested that relaxant responses to cromakalim are greater in SHR than WKY, and this may be due to the myogenic tone of aortic rings from SHR.

• 약학회지
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• 제33권6호
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• pp.333-338
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• 1989

It has been postulated that abnormal characteristics of central noradrenergic nervous system has been implicated in the development and maintenance of hypertension in several modes of experimental hypertension including spontaneously hypertensive rats (SHR). In the present study, we attempt to determine if abnormal characteristics of central noradrenergic nervous system in SHR is caused by genetic factors or hypertensive phenomena by evaluating the changes of central adrenoceptors after long-term treatment of clonidine. Animals were divided into three groups; (1) 14 week-old SHR; (2) age-matched normotensive Wistar rats (NW); (3) DOCA-Salt induced hypertensive rats (DS). Clonidine (100 ug/kg) or vehicle was injected intraperitonealy twice a day for 15 days. Changes of ${\alpha}_1-$ and ${\alpha}_2-receptor$ desities following clonidine treatment were determiend in frontal corte, medulla oblongata and hypothalamus using 3H-WB4101 and 3H-clonidine, respectively. Densities of ${\alpha}_1$ and ${\alpha}_2-receptors$ following clonidine treatment were not changed in frontal cortex and medulla oblongate of SHR as well as DS, but increased in frontal cortex of NW and decreased in medulla oblongata of NW. On the other hand, densities of ${\alpha}_1-receptors$ were increased and densities of ${\alpha}_2-receptors$ were not changed in hypothalamus of SHR but densities of ${\alpha}_1-$ and ${\alpha}_2-receptors$ were decreased in hypothalamus of DS as well as NW. These results suggest that such differences in frontal cortex and medulla oblongata of SHR may be results of hypertensive phenomena whereas those in hypothalamus may be relevant to genetic factors of SHR.

• Biomolecules & Therapeutics
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• 제12권1호
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• pp.19-24
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• 2004

The vascular relaxant effect of amlodipine adipate, a new salt of amlodipine, was evaluate in isolated rat aorta, and compared with that of amlodipine besylate. Furthermore, antihypertensive effects were measured in hypertensive rat models, such as spontaneously hypertensive rats (SHR) and rena1 hypertensive rats (RHR). Amlodipine adipate concentration-dependently inhibited $Ca^{2+}$-induced contraction of rat aorta with a very slow onset of action (reached its maximum at 3.5 h;$IC_{50}$: 3.76 nM), having a pattern and a potency similar to those of amlodipine besylate ($IC_{50}$: 4.01 nM). In SHR and RHR, orally administered amlodipine adipate produced a dosedependent and long-lasting (>10-24 h) antihypertensive effect ($ED_{20}$: 2.48 and 1.57 mg/kg, respectively), with a pattern and a potency similar to those of amlodipine besylate ($ED_{20}$: 2.50 and 1.99 mg/kg in SHR and RHR, respectively). These results suggest that amlodipine adipate is a potent and long-lasting antihypertensive agent and that its antihypertensive effect is not significantly different to that of amlodipine besylate.

• Journal of Nutrition and Health
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• 제29권10호
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• pp.1087-1095
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• 1996

The study was carried out to investigate a new type of functional foods with hypotensive effect which is critical in the prevention and treatment of hypertension and related circulatory diseases. The experimental diets(A, B, C) were prepared from plant based ingredients such as buckwheat, potato, perilla seed with different ratios formulated as an edible form appropriate for human consumption according to AIN-77 standard. Control group(D) was fed commercial rat chow. Twety-four 15-week-old SDR(Sprague Dawley rats) and twenty-four 20-week-old SHR(spontaneously hypertensive rats), weighing 200g respectively, were assigned to 4 treatments of 6 rats each in a completely randomized design. Blood pressure was measured at 7 day interval by tail-cuff sphygmomanometer using an IITC cuff pump and amplifier. The growth rates of both SHR and SDR were not statistically different in comparions with the control except those of diet B and C in SDR and SHR, respectively(p<0.05). When exprimental diets were fed, systolic blood pressure of SDR and SHR at day 28 had been lowered by 17-20 mmHg(ave. of 19.6mmHg for both strains) compared with the reference pressure at day 0. The levels of HDL-cholesterol were increased, while the levels of LDL-cholesterol consistently decreased in both strains when experimental diets were fed(p<.05). Plasma total cholesterol levels were not different among treatments. Plasma triglyceride levels were higher in control diet(commercial rat chow) due to two times higher fat content of control diet itself(p<.05). Atherogenic indices were lower compared to those of control when the experimental diets were fed in both strains (p,.05). The results suggest that the antihypertensive diets mainly consisting of plant-based ingredients may possibly effective in relieving hypertension as well as circulatory diseases.

• 생명과학회지
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• 제22권5호
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• pp.665-670
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• 2012

이 연구는 자연발생고혈압쥐(SHR)의 혈압, 골격근에서의 혈관생성 및 혈관내피세포성장인자 발현(VEGF)에 미치는 지구성운동의 효과를 조사하였다. 5주령 SHR와 WKY는 무작위로 정상혈압군(WKY, Wistar-Kyoto rat, n=9), 고혈압통제군(SHR-C, SHR Control, n=9) 및 고혈압운동군(SHR-E, SHR Exercise, n=9)으로 각각 분류하였고, 지구성운동은 트레드밀을 이용하였다(12-20 m/min, 0% grade, 60 min/day, 5 days/wk, 16 wk). 수축기혈압은 지구성운동에 의해 효과적으로 감소되었다(SHR-E vs. SHR-C, $p$ <0.05). 골격근의 모세혈관밀도와 VEGF 단백발현은 고혈압통제군(SHR-C)이 정상혈압군(WKY)보다 모두 감소되었으나, 지구성운동(SHR-E)이 고혈압통제군(SHR-C)에 비해 모두 증가되었다. 이러한 결과들은 지구력운동 트레이닝이 SHR 골격근의 VEGF 단백발현의 증가를 통해 모세혈관밀도를 향상시키고, 이러한 모세혈관밀도의 향상이 SHR의 혈압상승을 억제할 수 있다는 것을 의미한다.

• Journal of Ginseng Research
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• 제21권2호
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• pp.125-132
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• 1997

Our previous study showed that in vivo treatment of spontaneously hypertensive rats (SHR) with protopanaxatriol ginsenosides (PPT) reduces the blood pressure and inhibits the con- tractions induced by endothelium-derived contracting factor (prostaglandin endoperoxide ($PGH_2$) and superoxide anion) in aorta isolated from SHR. The aim of the present study is to examine whether PPT improves endothelial functions in the isolated thoracic aorta of SHR in vitro. Treatments of aortic rings with PPT, purified ginsenoside $Rg_1$ ($Rg_1$) or indomethacin normalized endotheliuln-dependent relaxation to acetylcholine, but not with protopanaxadiol ginsenosides (PPD) and purified ginsenoside Rb1 (Rb1). The effects of PPT were dose-dependent. PGH,- and oxygen free radical-inducted contractions in rat aorta without endothelium were inhibited by PPT or $Rg_1$, but not by PPD or $Rb_1$. Contractions induced by PGF2$\alpha$, U-46619, a stable thromboxane A2 agonist or KCI (60 mM) were not inhibited by PPT, $Rg_1$ or $Rb_1$. These findings demonstrate that PPT but not PPD scavenges the oxygen-derived free radicals and/or antagonize the effects of $PGH_2$ in the vascular smooth muscle and may explain the hypotensive effect of ginseng in the SHR.

• Advances in Traditional Medicine
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• 제8권4호
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• pp.430-439
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• 2008

Chungpaesagan-tang (CPSGT) is most frequently used to treat ischemic brain injury in tradition Korean medicine. Clinically, cerebral ischemia is likely to be accompanied by preexisting or complicating disease. However, animal models used to examine the effects of herbal medicines on cerebral ischemia have not given this issue sufficient consideration. The present study was undertaken to determine the effects of CPSGT on focal cerebral ischemia in normal and SHR rats subjected to transient middle cerebral artery occlusion (MCAO). Animals were divided into four groups: Normal (Sprague-Dawley) rats subjected to MACO (the NC+MCAO group), normal rats subjected to MCAO and then administered CPSGT (NC + MCAO + CP), SHR rats subjected to MCAO (SHR + MCAO), and SHR rats subjected to MCAO and then administered CPSGT (SHR + MCAO + CP). MCAO was performed using the intraluminal method. CPSGT was administrated orally twice (1 and 4 h) after MCAO. All animals were sacrificed at 24 h postoperatively. Brain tissues were stained with hematoxylin & eosin, to examine the effect of CPSGT on ischemic brain tissues. In addition, changes in TNF-$\alpha$ expression in ischemic areas were examined by immunostaining. CPSGT was found to significantly reduce infarction areas in normal and SHR rats and infarction volumes in SHR rats. Similarly, CPGST markedly increased neuron numbers and sizes in all treated groups, except cell sizes in SHRs. Furthermore, CPSGT reduced TNF-$\alpha$ expression in MCAO administered SHR rats. The findings of the present study suggest that CPSGT effectively ameliorates neuron damage caused by MACO-induced cerebral ischemia, and that it has a significant neuroprotective effect after cerebral ischemia in SHR.