• Radiation Oncology Journal
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• v.9 no.1
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• pp.7-15
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• 1991

Pentoxifylline (PENTO) has been known to improve RBC fluidity, and thus improve the flux of RBC through narrow capillaries. Additionally, PENTO also decreases the $O_2$ affinity of hemoglobin by increasing 2,3-DPG levels, thereby increasing the $O_2$ release from RBC. Nicotinamide (NA) has been reported to decrease the number of acutely hypoxic cells in tumors by temporarily increasing tumor blood flow. Therefore, the purpose of this study was to examine whether the combination of PENTO and NA (PENTO+NA) would reduce the radioresistance of the Fsall murine fibrosarcoma by oxygenating the hypoxic cells. We obsewed a significantly enhanced radiation-induced growth delay of the FSaII tumors by PENTO+NA. Thus the enhancement ratio was between 2.5 and 2.8 in growth delay assay. The $TCD_{50}$ of control tumors was about 57 Gy, but that of PENTO+NA treated tumors was about 32Gy. Thus $TCD_{50}$ was modified by a factor of 1.8. We also observed that PENTO+NA exerted no effect on the radiation-induced skin damage after the legs without bearing tumors were exposed to X-irradiation. In order to clarify radiosensitizing effects of PENTO+ NA, changes in tumor blood flow and intratumor pOf were measured using laser Doppler flowmetry and $O_2$ microelectrode methods. The tumor blood flow significantly increased at 10 min. after injection of PENTO+ NA. Furthermore, we also found that PENTO+ NA significantly increased intratumor $pO_2$ from 8 to 19 mmHg. We concluded that PENTO+MA was far more effective than NA alone or PENTO alone. The increase in the response of tumors in vivo to X-irradiation appeared to be due mainly to an increase in the tumor oxygenation. Further studies using various concentrations of PENTO alone and in combination with NA to obtain better sequencing and maximal radiosensitization are warranted.

• Journal of Acupuncture Research
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• v.18 no.5
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• pp.147-154
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• 2001

Amun(GV15), Habkook(LI4) and Shinsu(B23) have been used as a meridian point for apoplexy, hypertention, vertigo etc. The effects of GV 15, LI4 and B23 on the vascular system is not known. The purpose of this Study was to investigate the effect of several meridian points on the regional cerebral bloof flow(rCBF), mean arterial blood pressure(BP) in rats. The changes of BP and rCBF were tested Laser-Doppler Flowmetry(LDF). Results : The results of this Study were obtained as follows ; 1. GV15 and LI4 were increased significantly rCBF. 2. GV15, LI4 and B23 were increased BP, but have not significance. Conclusion : This results suggest that GV15 was increased rCBF by increasing pial arterial diameter, and LI4 was increased rCBF by increasing BP.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.4
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• pp.167-172
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• 2006

In the present study, we developed a simple method to predict the neuronal cell death in the mouse hippocampus and striatum following transient global forebrain ischemia by evaluating both cerebral blood flow and the plasticity of the posterior communicating artery (PcomA). Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral occlusion of the common carotid artery (BCCAO) for 30 min. The regional cerebral blood flow (rCBF) was measured by laser Doppler flowmetry. The plasticity of PcomA was visualized by intravascular perfusion of India ink solution. When animals had the residual cortical microperfusion less than 15% as well as the smaller PcomA whose diameter was less than one third compared with that of basilar artery, neuronal damage in the hippocampal subfields including CA1, CA2, and CA4, and in the striatum was consistently observed. Especially, when mice met these two criteria, marked neuronal damage was observed in CA2 subfield of the hippocampus. In contrast, after transient BCCAO, neuronal damage was consistently produced in the striatum, dependent more on the degree of rCBF reduction than on the plasticity of PcomA. The present study provided simple and highly reproducible criteria to induce the neuronal cell death in the vulnerable mice brain areas including the hippocampus and striatum after transient global forebrain ischemia.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.5
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• pp.581-589
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• 1997

This study was undertaken to examine the effects of ultraviolet light (UVL) and rebamipide on the cutaneous blood flow and tissue survival on rabbit skin flap. In a random bipedicle flap, Laser Doppler Flowmetry (LDF) was employed to measure the blood flow of flap (BFF). Wound Margin Strength (WMS) measured by force transducer and Light microscophy were used for evaluation of tissue viability. Single exposure to UVL increased the BFF gradually for more than 15 hours, and decreased the vasoconstrictor effect of intravenous phenylephrine. The UVL-induced increase in BFF regressed after 18 hours of irradiation, and this regression was tended to be enhanced by intradermal injection of L-NAME, a nitric oxide synthase (NOS) inhibitor, but the regression was significantly reversed by acetylcholine, an endothelial constitutive NOS (cNOS) activator and L-arginine, an NO precusor. Rebamipide, a novel antiulcer agent known to scavenge the hydroxyl radical, abruptly reversed the spontaneous regression of the UVL- induced increase in BFF by the same manner as L-arginine. In ischemic skin flap, rebamipide increased the BFF abruptly by the same manner as sodium nitroprusside (SNP), an NO doner, while N-acetylcystein (NAC), a free radical scavenger, gradually increase the BFF. The rebamipide-induced increase in BFF was sustained at the level of the SNP-induced increase in BFF during the late period of experiment. Rebamipide increased the WMS of skin flaps and prevented the tissue necrosis in comparison with L-NAME. Based on these results, it is concluded that in rabbit skin, UVL irradiation increases the BFF by NO release, and rebamipide exerts a protective effect on the viability of ischemic skin flaps by either or both the increase in BFF by NO release and free radical scavenger effect.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.3
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• pp.507-513
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• 2002

Jaeumgenby-tang(JGT) have been used in oriental medicine for many centries as a a therapeutic agent of vertigo caused by deficiency of qi and blood. The effects of JGT on the regional cerebral blood flow(rCBF), mean arterial blood pressure(MABP) and cardiac muscle contractile force(CMF) is not known. The purpose of this Study was to investigate effects of JGT on the rCBF, MABP, CMF and mechanism of JGT induced changed rCBF, MABP, CMF. The changes of rCBF, MABP and CMF were determinated by Laser-Doppler Flowmetry(LDF). The results were as follows; JGT extract was increased rCBF, MABP and CMF in a dose-dependent, specially JGT extract was significantly increased rCBF and MABP. Pretreatment with propranolol was significantly inhibited JGT induced increase of rCBF but pretreatment with indomethacin and methylene blue were accelerated JGT induced increase of rCBF. Pretreatment with propranolol and indomethacin were inhibited JGT induced increase of MABP, but pretreatment with methylene blue was accelerated JGT induced increase of MABP. Pretreatment with propranolol was significantly inhibited JGT induced increase of CMF but pretreatment with indomethacin and methylene blue were accelerated JGT induced increase of CMF. This results suggest that JGT increased rCBF by increasing MABP and CMF and the action of JGT is mediated by adrenergic β-receptor.

• Herbal Formula Science
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• v.7 no.1
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• pp.121-130
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• 1999

Oriental medicine prescription has been used for the treatment of various clinical symptoms associated with cerebral apoplexy. However, single herb drug does not used cerebral apoplexy and there mechanisms of action have not been defined, and it is not yet known what effects they have on the hemodynamics of cerebral circulation. The study was aimed to investigate the effect batryticatus bombycis(BB) on the vascular systems including changes in blood pressure (BP), and regional cerebral blood flow (rCBF) and of male Sprague-Dawely rats. The changes in rCBF were determinated by laser-Doppler flowmetry. 1. Blood pressure was not affected by BB in rats. 2. rCBF was increased by BB in a dose-dependent manner. 3. Pretreatment with methylene blue(1mg/kg), and propranolol(1mg/kg) did not inhibited BB induced increased in rCBF. 4. Pretreatment with propranolol(1mg/kg) was increased by BB in a dose-dependent manner in blood perssure. 5. Pretreatment with ODQ($10{\mu}g/kg$) and L-NNA(1mg/kg) were inhibited BB induced increased in rCBF. 6. Pretreatment with L-NNA(1mg/kg) was increased rCBF in a dose-dependent manner. These results suggest that BB causes a diverse response of blood pressure and regional cerebral blood flow(rCBF). The increased in rCBF is also mediated by nitric oxide synthease and guanylate cyclase.

• Culinary science and hospitality research
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• v.20 no.5
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• pp.67-70
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• 2014

The purpose of this study was to measure the changes of regional cerebral blood flow(rCBF) and blood pressure(BP) in rats, following the intravenous injection of Flos Sophora japonica L.(FSJ) water extract. The measurement was continually monitored by Laser-Doppler Flowmeter and pressure transducer in anaesthetized adult Sprague-Dawley rats for 2 hours to 2 hours and a half through the data acquisition system. FSJ increased the changes of rCBF in rat significantly. The rCBF of FSJ did not change by pretreated propranolol, atropine, L-NNA($N^G$-nitro-L-argininine) and indomethacin. But the rCBF of Flos Sophora japonica L. was increased by pretreated methylene blue. FSJ decreased the changes of BP, significantly. The BP of FSJ did not change by pretreated propranolol, atropine, L-NNA and indomethacin. But the BP FSJ was decreased by pretreated methylene blue. There results indicated that FSJ can increase the rCBF and decrease the BP, that is related to guanylyl cyclase activity.

• Archives of Reconstructive Microsurgery
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• v.4 no.1
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• pp.1-8
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• 1995

장시간 허혈상태의 토끼 이개를 실험대상으로 하여 유로키나제와 헤파린을 병용 또는 단독으로 사용시와 또한 약물을 사용하지 않았을 때, 이들이 모세혈관의 개존성과 아울러 미세수술후의 조직 생존율에 미칠 수 있는 효과를 보기 위하여 허혈상태의 토끼 이개를 미세수술로 접합한 후 모세혈관으로의 혈류를 측정하기 위하여 레이저 초음파 혈류측정기(Laser doppler flowmetry)를 이용하였으며 방사선 구슬들(Cobalt-57 with plastic material with average diameter 15 micron)을 주입한 결과 유로키나제 조합에서 통계적으로 유효한 성적을 얻었다. 광학현미경 소견은 유로키나제와 헤파린을 병용한 조합에서 모세혈관내 내피세포의 배열이 유지되어 있었으며 헤파린을 사용한 조합에서도 유사한 소견을 보였으나 약물을 사용하지 않은 조합에서는 국소적인 내피세포의 배열이 결핍되어 있었다. 전자현미경 소견에서 유로키나제와 헤파린을 병용한 조합에서 내피세포가 혈관내벽에 배열되어 있었고 또 불규칙한 세포질이 돌출되어 있었다.

• The Journal of Internal Korean Medicine
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• v.27 no.4
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• pp.855-863
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• 2006

Objectives : This study was performed to evaluate effects of Yangsim-tang extract (YST) on hemodynamics (regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) ) in normal rats, and effects of cyclooxygenase and guanylate cyclase under YST. Methods : Laser-Doppler flowmetry (LDF) measured changes of rCBF, and a data acquisition system assembled with MacLab and Macintosh measured changes of MABP. Results : YST significantly increased rCBF, but did not change MABP. Pretreatment with indomethacin significantly inhibited rCBF increased by YST, but pretreatment with methylene blue did not significantly inhibit rCBF increased by YST. Conclusions : YST increases rCBF, and the action of this response is mediated by cyclooxygenase.

• Biomolecules & Therapeutics
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• v.7 no.3
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• pp.234-241
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• 1999

The present study assessed the cerebroprotective effect of platelet-activating factor(PAF) antagonists in transient cerebral ischemia of rats. Right middle cerebral artery (MCA) of Sprague-Dawley rats was occluded for 2 hours using an intraluminal filament technique, and was reperfused for 6 hours following cerebral ischemia. The infarct area of seven coronal brain slices was measured morphometrically following stain ing in the 2% 2,3,5-triphenyltetrazolium chloride solution. The changes in regional cerebral blood flow (rCBF) and pial arteriolar diameter were measured by laser-Doppler flowmetry and by a videomicroscopy, respectively. The infarct size was significantly reduced by PAF antagonists, BN 52021 and CV-6209, which were administered i.p. 10 min before MCA occlusion. Pretreatment with PAF antagonists significantly restored the changes in pial arterial diameter as well as those in rCBF during the period of cerebral ischemia-reperfusion. PAF antagonists significantly inhibited the inducible nitric oxide synthase activity in the pial arteries ipsilateral to ischemia. These results suggest that PAF antagonists exert a cerebroprotective effect against ischemic brain damage through an improvement of postocclusive cerebral blood flow.