• 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.

• 약학회지
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• 제35권5호
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• pp.394-400
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• 1991

A question whether abnormal responsiveness of hypothalamic catecholaminergic nervous system to ovarian steoid hormones in spontaneously hypertensive rats (SHR) exist was investigated. Four groups of experimental animals were prepared for SHR and normotensive Wistar rats (NW) respectively: 1) intact, 2) ovariectomized (OVX+V), 3) ovariectomized and estrogen treated (OVX+E), 4) ovariectomized and estrogen plus progesterone treated (OVX+E+P) groups. Hypothalami from experimental animals were dissected out and used for determination of .alpha.-adrenergic receptor binding characteristics and catecholamine contents. Norepinephrine(NE) content and B$_{max}$ of $\alpha_1$-adrenergic receptors in hypothalami were greater in intact SHR than in intact NW, but dopamine(DA) content was lower in SHR than in NW. Neither contents of NE and DA nor binding characteristics of $\alpha_1$-adrenergic receptors were different in OVX+V and OVX+E group from intact group of both SHR and NW. Kd and B$_{max}$ of $\alpha_1$-adrenergic receptors in OVX+E+P was lower than that in intact SHR but not in NW. DA content was lower in OVX+E+P than in intact group of SHR and NW. The result of the present study indicates that there is an abnormal responsiveness of hypothalamic catecholaminergic nervous system to ovarian steroid hormones in SHR which may be one of genetically-determined factors probably not responsible for the development of hypertension.

• 한국통신학회논문지
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• 제24권10B호
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• pp.1832-1840
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• 1999

논문에서는 WDM 기술을 사용하는 완전 광전달망에서 장애를 복구할 수 있는 양 방향 BLSR/4 WDM/SHR 구조의 네트워크를 설계하였다. 제안한 네트워크는 전기적 기능이 없는 완전 광소자를 사용하여 높은 수준의 투명성을 제공하고, BLSR/4 SHR 구조를 사용함으로써 장애 복구를 효율적으로 수행할 수 있다. 또한, 제안한 BLSR/4 WDM/SHR의 여러 장애에 대한 생존성을 분석하기 위한 모델을 제시하였으며, 전파 시간, 처리 시간, 절체 시간의 파라미터를 사용하여 복구 성능을 분석하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제3권1호
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• pp.29-34
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• 1999

The hyperactivity of cholinergic system in the RVLM of spontaneously hypertensive rats (SHR) may contribute to the sustained elevation of blood pressure. However, the hyperactivity mechanisms of cholinergic system are controversial. Thus, to clarify the mechanisms of cholinergic hyperactivity in RVLM of the SHR, we studied the activities of enzymes that participate in the biosynthesis and degradation of acetylcholine (ACh) and the density of muscarinic receptors in RVLM of the 14- to 18-week-old SHR and age-marched Wistar Kyoto rats (WKY). Choline acetyltransferase activity was far greater in RVLM of SHR than that of WKY. $[^3H]ACh$ release from RVLM was also greater in SHR than in WKY. Acetylcholinesterase activity and $[^3H]NMS$ binding of RVLM slice of SHR were not significantly different from that of WKY. These results suggest that the enhanced cholinergic mechanisms in the RVLM of SHR is due to the enhanced presynaptic cholinergic tone rather than the altered postsynaptic mechanisms.

• 대한약리학회지
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• 제31권1호
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• pp.17-26
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• 1995

8주, 18주, 그리고 32주된 Spontaneously Hypertensive Rats (SHR)과 Wistar-Kyoto Rats(WKY)과의 blood pressure(혈압)를 측정하여본 결과 SHR 그룹이 WKY에 비해 19에서 70 mmHg 차이로 SHR 그룹이 WKY group에 비하여 혈압이 높았다. 18주된 SHR과 WKY에서 제 3 뇌실내 (intraventricular)로 투여된 morphine과 ${\beta}-endorphin$의 진통작용을 검색하여 보았다. WKY group에 비하여 SHR group에서 뇌실내로 투여된 ${\beta}-endorphin$은 진통작용에 있어서 상승작용 (potentiation)을 보임을 발견하였고 뇌실내로 투여된 morphine은 SHR group에서 약간만 상승작용을 보였다. SHR과 WKY group간에 opioid의 진통작용에 있어서 중요한 역할을 하는 Midbrain과 Medulla (pons), 그리고 spinal cord (척수)의 lumbar부위의 $[Met^5]-enkephalin$과 proenkep-halin A mRNA level을 측정하여 보았다. SHR과 WKY group간의 $[Met^5]-enkephalin$과 proenkephalin mRNA의 양은 별로 차이를 보이지 않았다. 이러한 결과로 미루어 볼때 SHR group에서 뇌실내로 투여된 ${\beta}-endorphin$은 그의 진통효과에 있어서 보인 상승작용은 척수상부에 위치하고 있는 opioid deptide의 양이 변해서가 아니라 다른 기전에 의하여 조절되어지고 있음을 시사한다.

• The Korean Journal of Physiology and Pharmacology
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• 제13권4호
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• pp.309-313
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• 2009

Spontaneous hypertensive rats (SHR) are an established model of genetic hypertension. Vascular smooth muscle cells (VSMC) from SHR proliferate faster than those of control rats (Wistar-Kyoto rats; WKY). We tested the hypothesis that induction of heme oxygenase (HO)-1 induced by aprotinin inhibits VSMC proliferation through cell cycle arrest in hypertensive rats. Aprotinin treatment inhibited VSMC proliferation in SHR more than in normotensive rats. These inhibitory effects were associated with cell cycle arrest in the G1 phase. Tin protoporphyrin IX (SnPPIX) reversed the anti-proliferative effect of aprotinin in VSMC from SHR. The level of cyclin D was higher in VSMC of SHR than those of WKY. Aprotinin treatment downregulated the cell cycle regulator, cyclin D, but upregulated the cyclin-dependent kinase inhibitor, p21, in VSMC of SHR. Aprotinin induced HO-1 in VSMC of SHR, but not in those of control rats. Furthermore, aprotinin-induced HO-1 inhibited VSMC proliferation of SHR. Consistently, VSMC proliferation in SHR was significantly inhibited by transfection with the HO-1 gene. These results indicate that induction of HO-1 by aprotinin inhibits VSMC proliferation through cell cycle arrest in hypertensive rats.

• Biomolecules & Therapeutics
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• 제8권1호
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• pp.27-31
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• 2000

The aim of this study was to investigate a potential effect of treatment of spontaneously hypertensive rats (SHR) with Pini Folium or Leonuri Herba extracts. Male SHR were treated with extracts for 2 or 4 weeks starting at 13 weeks of age. We found that oral treatment with the methanol extract from Pini Folium or Leonuri Herba (1g/Kg/day) significantly decreased mean blood pressure to 85.4% and 78.6% respectively in compare with untreated control SHR. Treatment with the extract from Pini Folium for 4 weeks during hypertension development phase (starting 9 weeks of age) resulted in a partial prevention of hypertension development. There were no significant differences for body weight between untreated and Pini Folium treated SHR.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 제3회 추계심포지움
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• pp.115-124
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• 1995

The purpose of the present study was to address whether the in vivo noradrenergic neural activities in the locus coeruleus are involved in the regulation of blood pressure. Two groups of the animals were prepared, 1) SHR and 2) age-matched normotensive control, WKY. At the age of 6 and 16 weeks, blood pressure and the releases of NE from the locus coeruleus in SHR and KWY were measured by in vivo microdialysis at three different conditions: 1) normal, 2) elevated state of blood pressure by systemic injected phenylephrine and 3) increased state of neural activity by perfused phenylephrine into the locus coeruleus. The basal release of NE of SHR were significantly higher than that of WKY, Phenylephrine treatment caused elevation of blood pressure in both SHR and WKY in dose-dependent manner. Following phenylephrine injection, the releases of NE from the locus coeruleus of SHR were significantly decreased, whereas the significant change of NE in WKY was observed in the highest dose of phenylephrine. Phenylephrine perfusion into the locus coeruleus through microdialysis probe caused pressor responses and the pressor response in SHR was greater compared with that in WKY. The results from the present study suggests that the noradrenergic nervous system in the locus coeruleus may contribute as one of the development and maintenance factors for hypertension in SHR.

• Molecules and Cells
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• 제45권4호
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• pp.243-256
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• 2022

Transcriptional regulation, a core component of gene regulatory networks, plays a key role in controlling individual organism's growth and development. To understand how plants modulate cellular processes for growth and development, the identification and characterization of gene regulatory networks are of importance. The SHORT-ROOT (SHR) transcription factor is known for its role in cell divisions in Arabidopsis (Arabidopsis thaliana). However, whether SHR is involved in hypocotyl cell elongation remains unknown. Here, we reveal that SHR controls hypocotyl cell elongation via the transcriptional regulation of XTH18, XTH22, and XTH24, which encode cell wall remodeling enzymes called xyloglucan endotransglucosylase/hydrolases (XTHs). Interestingly, SHR activates transcription of the XTH genes, independently of its partner SCARECROW (SCR), which is different from the known mode of action. In addition, overexpression of the XTH genes can promote cell elongation in the etiolated hypocotyl. Moreover, confinement of SHR protein in the stele still induces cell elongation, despite the aberrant organization in the hypocotyl ground tissue. Therefore, it is likely that SHR-mediated growth is uncoupled from SHR-mediated radial patterning in the etiolated hypocotyl. Our findings also suggest that intertissue communication between stele and endodermis plays a role in coordinating hypocotyl cell elongation of the Arabidopsis seedling. Taken together, our study identifies SHR as a new crucial regulator that is necessary for cell elongation in the etiolated hypocotyl.

• The Korean Journal of Physiology and Pharmacology
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• 제6권1호
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• pp.57-61
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• 2002

The renoprotective activities of white ginseng radix and rootlet were compared in spontaneously hypertensive rat (SHR) with diabetes. During oral administration of white ginseng radix (Ginseng Radix Alba, GRA) and white ginseng rootlet (Ginseng Radix Palva, GRP) for four weeks, arterial blood pressure and blood glucose levels were determined at every 10 days. In both GRA- and GRP-treatment groups, arterial blood pressures started to go down after 10 days of administration and maintained throughout the study period. After four weeks administrations of GRA and GRP, diastolic blood pressures were significantly decreased with 17% and 9%, respectively. GRA treatment also decreased blood glucose levels after 10 days of administration when compared with diabetic SHR group. At the end of the experiment, serum creatinine (Scr) and blood urea nitrogen (BUN) were not significantly different between the groups, except 62% higher value of BUN in diabetic SHR group when compared with SHR group. In the diabetic SHR group, the excretion of urinary albumin was increased significantly when compared with SHR. The level of urinary albumin in GRA treated group was markedly reduced when compared with diabetic SHR group $(67.8{\pm}4.7\;vs.\;131.3{\pm}13.5\;mg/24\;h).$ To examine the effects of ginseng radices on an overt diabetic nephropathy, index of kidney hypertrophy and transforming growth $factor-{\beta}1\;(TGF-{\beta}1)$ protein levels were evaluated. The glomerular and tubular cells stained positive for $TGF-{\beta}1$ seemed to be more abundant in diabetic SHR than in those with SHR, and GRA treated rats showed somewhat less $TGF-{\beta}1$ protein in glomerular and tubular cells when compared with diabetic SHR. Our results suggest that GRA might be a useful antihypertensive and antidiabetic agent with renoprotective effect.