• Journal of Nutrition and Health
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• 제28권2호
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• pp.115-126
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• 1995

The effects of energy-yielding substrates on coronary circulation, myocardial oxygen metabolism, and intramyocytic adenylates of perfused Wistar control rat(WC) and spontaneously hypertensive rat(SHR) hearts were examined under basal and $\beta$-adrenergic stimulation conditions. The perfusion medium (1.0mM Ca2+) contained 5mM glucose (+5U/l insulin) in combination with 5mM pyruvate, 5mM lacate, 5mM acetate, or 5mM octanoate as energy substrates. Hearts were perfused with each substrate buffer for 20min under basal conditions. Coronary functinal hyperemia was induced by infusing for 20min isoproterenol (ISO, 1uM), a $\beta$-receptor agonist. Cardiac adenylates, glycolytic intermediates, and coronary venous lactate were measured by using an enzymatic analysis technique. Under basal conditions, acetate and octanoate significantly increased coronary flow(CF) of WC in parallel with myocardial oxygen consumption. However, CF of SHR was partly attenuated by coronary vasoconstriction despite metabolic acidosis. In addition, pyruvate and lactate depressd ISO-induced coronary functional hyperemia in SHR. It should be noted that octanoate exhibited coronary dysfunction under ISO conditions. On the other hand, fat substrates depleted myocardial high energy phosphate pool and accumulated breakdown intermediates. In SHR with coronary vasoconstriction under basal conditions, and with depressed coronary functional hyperemia, high energy phosphates were greatly depleted. These results suggest that energy substrates in the myocardium and coronary smooth muscle alter remarkably coronary circulation, and that coronary circulatory function is associated with a reserve of high energy phosphates and a balance between breakdown and nono synthesis of energy phosphates. These findings could be explained by alterations in the cytosolic redox state manipulated by LDH and hence in the cytosolic phosphorylation potential, which might be involved in hypertension of SHR.

• Preventive Nutrition and Food Science
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• 제6권1호
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• pp.43-50
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• 2001

The effects of cardiac ischemia-reperfusion and $\beta$-adrenergic stimulation on metabolic function and energetics were investigated in Lan gendorff-perfused spontaneously hypertensive rat (SHR) hearts. Sarcoplasmic reticulum {TEX}$Ca^{2+}${/TEX}-dependent ATPase and cardiac lactate dehydrogenase (LDH) are additionally studied. The perfusion medium (1.0 mM {TEX}$Ca^{2+}${/TEX}) contained 5 mM glucose(+5 U/L insulin) and 2 mM pyruvate as substrates. Global ischemia was induced by reducing perfusion pressure of 100 to 40 cm {TEX}$H_{2}${/TEX}O, followed by 20 min reperfusin. Isoproterenol (ISO, 1$\mu$M) was infused for 10 min. Coronary vascular resistance and myocardial oxygen consumption ({TEX}$MVO_{2}${/TEX}) of SHR were increased in parallel with enhanced venous lactate during ischemia and reperfusion compared to those of Sprague Dawley (SD) hearts. Although ischemia-induced increase in venous lactate and combined adenosine plus inosine was abolished, coronary vasodilation produced in SD during reperfusion. In SHR, depressed reactive hyperemia was associated with a fall in cardiac ATP and CrP/Pi ratio and a rise in intracellular lactate/Pyruvate ratio. On the other hand, ISO produced coronary functional hyperemia and an increase in {TEX}$MVO_{2}${/TEX}. However, these responses were less than those in SHR hearts. The ATPase activity of SHR was attenuated in free {TEX}$Ca^{2+}${/TEX} concentrations used under basal condition and with ISO compared to that of SD. Venous lactate output and cardiac LDH activity were augmented in SHR as influenced by ISO. These results demonstrate that coronary reactive and functional hyperemia was dpressed in SHR, which cold be explained by alterations in the cytosolic phosphorylation potential and the cytosolic redox state manipulated by LDH, and by abnormal free calcium handling.

• 한국임상수의학회지
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• 제20권4호
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• pp.449-457
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• 2003

To investigate the renal effects of enrofloxacin administration on rats induced with dehydration or hyperoxaluria, male rats were treated with enrofloxacin of 50 mg to 500 mg/kg b.w.. The microscopical observations of kidney and urine sediment were carried out in the experimental groups. The result obtained were as follows; The male rats deprived of water for 72 hours and administered with enrofloxacin. As enrofloxacin administration dose was increased, clinical signs such as loss of appetite, depression, weakness, and loss of urine output became more severe. In the histopathological findings, there were hyperemia and hemorrhage in renal cortex, vacuolation and necrosis of renal tubular epithelia, proteinous casts within renal tubules. The male rats were orally administered with sodium oxalate and injected with enrofloxacin for 7days. As enrofloxacin administration dose was increased, clinical signs such as the loss of appetite and water consumption, and weakness became more severe. In the histopathological findings, there are hemorrhage of glomeruli and cortical hyperemia, vacuolation and necrosis of tubular epithelia, proteinous casts in renal tubules. In the microscopical findings of urine sediment, there are calcium oxalate crystal (diamond-like type) and magnesium ammonium phosphate crystals (rhomboid). The male rats were intraperitoneally injected with sodium oxalate and administered with enrofloxacin for 7days. As enrofloxacin administration dose was increased, clinical signs such as the loss of appetite and water consumption, weakness were more severe. In the histopathological findings, there were hyperemia and hemorrhage in both glomeruli and renal cortex. Severe necrosis of renal tubular epithelia, bluish materials within renal tubules were also found. In the microscopical findings of urine sediment, there were many calcium oxalate crystals. The present results suggest that enrofloxacin has some injurious effects in rats having dehydration or hyperoxaluria, and clinically, we should consider these renal injury effects when we use enrofloxacin in patients accompanied renal disease, dehydration and hyperoxaluria conditions.

• Toxicological Research
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• 제13권1_2호
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• pp.1-21
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• 1997

염증반응이란 우리 신체에 외부 물질이 침입했을 경우 대처하는 정상적인 현상이다. 외부에서 물리, 화학, 생물학적 물질에 노출되었을 경우 혈관이 팽창하고, 비특이적 면역반응이 시작된다. Selectin, integrin, immunoglobulin superfamily와 같은 adhesion molecule에 의해 macrophage 및 neutrophil과 같은 leukocyte의 반응을 촉진하기 위해 exudation이 일어나고 침입 부위에 모여 hyperemia가 발생된다.(Govan 등, 1995)

• 한국임상수의학회지
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• 제36권4호
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• pp.212-218
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• 2019

This study evaluates the drug delivery and biocompatibility of latanoprost imbedded disk in rabbit eye by assessing pharmacokinetics (PK), clinical signs, and histopathologic findings. During 84 days of experimental period, 48 New Zealand Rabbit (NZW) eyes were divided into control group which received no treatment and test material group which latanoprost were implanted intrasclerally. Pharmacokinetic assessment was performed to evaluate the drug delivery for 3 months. For biocompatibility, clinical signs were observed and histopathological analysis was done at 3 months post-operatively. The concentration of latanoprost in the iris tissue was maintained during the experimental period and the highest level of latanoprost was found at 4 weeks. However, the latanoprost was not found in the aqueous humor. Macroscopically, there was no evidence of clinical signs except for temporary hyperemia, neovascularization and edema immediately after surgery. On histopathological examination, there were no abnormal findings such as hyperemia, neovascularization, and edema in the eye tissues. The latanoprost imbedded disks has effectively released the drug into the adjacent tissue with high compatibility. Therefore, this study suggests that the drug delivery system with intrascleral latanoprost imbedded implants might be a novel approach as a treatment option for glaucoma.

• 대한약리학회지
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• 제23권1호
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• pp.15-23
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• 1987

만성 간문맥 고혈압에 동반하는 내장 충혈에 대한 발생 기전을 규명하기 위하여 고양이의 간문맥을 결찰하고 그 경과에 따라 비 -간 교감 신경성 반사 흥분의 변동과 동시에 순환 역동학적 변동을 관찰하였다. 1. 대조 고양이 (Sham 수술군)에서 비동맥을 통하여 capsaicin, bradykinin 및 vasopressin을 주사 하였을 매에는 전신 동맥압의 반사 흥분뿐만 아니라 비정맥압의 상승을 초래하였다. 그러나 심박동수는 변화가 없었다. 동시에 비장(비-비 반사) 및 간장 (비 -간 반사)에서 교감 신경의 만사 흥분을 일으켰다. 2. Capsaicin을 간 표면에 도포하였을 때는 간 신경 흥분 (간-간 반사)과 등시에 승압 반사를 유발시켰다. 3. 문맥 결찰 후에는 비정맥압은 시간 경과에 따라 증가 하였고 이에 동반하여 전신 동맥압은 감소하였다. 그러나 승압반사 항진은 제2일에 현저하게 야기되었고 그후 대조치로 회복되었다. 비-비 또는 비-간 교감 신경 반사 흥분은 제8일에 현저히 감약되었다. 4. 이상의 성적을 종합하면 비장 및 간장에 분포하는 교감 신경 반사 흥분은 동일한 중추 지배에 의하여 조절되고, 간문맥 결찰 후 내장 반사 흥분의 감소는 내장 충혈의 발생과 밀접한 관련이 있을 것으로 사료되었다.

• 대한치과의사협회지
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• 제12권3호
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• pp.195-198
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• 1974

The purpose of this study is to obtain the histopathological change of dentin and pulp when the prepared cavity is exposed to oral fluid without protection. The results were as follows: 1. Hyperemia of pulp blood vessel and round cell infiltration in odontoblast layer observed on the one week experimental dogs. 2. Marked edematous change, round cell infiltration, fibrotic change and prolif eration of collagenous fiber showed on the 8 week experimental dogs. 3. Prepared cavity should be protected by the biologically accepted lining mater ials regardless of cavity depth.

• 대한약침학회지
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• 제12권4호
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• pp.5-32
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• 2009

Objectives: This study was performed to analyse single dose toxicity of pure melittin(Sweet Bee Venom-Sweet BV) extracted from the bee venom by utilizing protein isolation method of gel filtration. Methods: All experiments were conducted at Biotoxtech, a non-clinical studies authorized institution, under the regulations of Good Laboratory Practice (GLP). Six weeks old female Sprague-Dawley rats were chosen for the pilot study and determined 30㎎/㎏ which is 4285 times higher than the clinical application dosage as the high dosage, followed by 15 and 7.5㎎/㎏ as mid and lose dosage, respectively. Equal amount of excipient to the Sweet BV experiment groups was administered as the control group. Results: 1. No mortality was witnessed in all of the experiment groups. 2. Hyperemia and movement disorder were observed around the area of administration in all groups, and higher occurrence in the higher dosage groups. Hyperemia and movement disorder diminished with elapsed time. 3. For the weight measurement, male groups showed larger reduction in weight in accordance with higher dosage. Female groups didn't s how significant changes. 4. To verify abnormalities of organs and tissues, cerebellum, cerebrum, liver, lung, kidney, and spinal nerves were removed and conducted histological observation with H-E staining. No abnormalities were detected in any of organs and tissues. 5. One female rat in the 30㎎/㎏ group had amputated toe near the administered area and histopathological finding was hemorrhage with inflammation. This is presumed as a secondary infection after the administration of Sweet BV. Conclusion: Above findings suggest Sweet BV is relatively s safe treatment medium. Further studies on the subject should be conducted to yield more concrete evidences.

• 한국정보처리학회논문지
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• 제3권5호
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• pp.1059-1069
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• 1996

본 논문의 목적은 메뉴 방식과 메타인지에 따라 학습한 학습자의 오류 및 오류 감지, 메뉴탐색 시간과 학업 성취도에 대한 상호작용의 효과와 메뉴방식과 학습시기(초 중 말기)가 기능관련 오류에 상호작용의 효과가 있는 가를 검증해 봄으로써 학습자 특성에 따라 학습효과를 높일 수 있는 메뉴를 선택하도록 하는데 있다. 본 논문에서는 한올 하이퍼미디어 학습 프로그램 학습시 주로 많이 사용되는 4가지 메뉴 방식(아이콘 메뉴, 아이콘텍스트 메뉴, 폴다운 메뉴, 폴다운 메뉴, 막대 선택 메뉴) 과학습자 특성의 메타인지가 발생되는 오류, 메뉴탐색 시간과 학업 성취도에 어떤 영향을 미치며, 메뉴방식과 학습시기에 따라 기능관련 오류에 어떤 영향을 미치는가를 경험적으로 검증해 보았다. 그 결과 메뉴방식은 하위 메타규제집단에서 영향을 미치게 되므로 아이콘텍스트 메뉴방식을 사용하는 것이 학업성취도를 높여주는 효과가 있다고 나타났다. 상위 메타규제집단에서는 어느 메뉴방식을 사용해도 학업성취도에는 차이가 없는 것으로 나타났다. 그리고 학습초기에 막대선택과 아이콘 메뉴방식이 상대적으로 기능관련 오류를 더 많이 범한 것으로 나타났다.

• 환경생물
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• 제22권1호
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• pp.133-140
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• 2004

유기주석화합물이 넙치의 기관계 구조에 미치는 독성을 알아보기 위하여 넙치를 대조구와 TBTO를 첨가한 6개 농도구(0.17, 0.36, 0.60, 3.20, 6.30, 12.50 ${\mu}g \;L^{-1}$)에서 42일 동안 노출 실험을 하였다. 조직상의 변화 정도는 노출 시간과 TBTO농도의 증가에 따라 심하게 나타났다. 저농도의 TBTO 노출구에서 관찰된 초기 조직학적 변화로는 아가미에서는 점액세포와 염세포의 활성, 새판 모세혈관의 충혈, 상피층의 비후, 간췌장에서는 간세포의 활성화와 췌장 효소원과립의 감소, 담관의 변성이 확인되었으며, 신장에서는 모세혈관의 충혈, 호산성세포와 혹색 대식세포군의 출현이 관찰되었다. 고농도의 TBTO 노출구에서 관찰된 조직학적 변화로는 아가미에서는 새판 상피층의 박리와 새판의 붕괴, 간췌장에서는 간세포의 핵응축, 세포질의 혼탁 및 과립변성, 신장에서는 조혈세포의 핵응축, 사구체와 세뇨관의 붕괴 등 정상적인 기능 수행이 어려울 것으로 판단되는 조직상들이 관찰되었다. 이와 같은 결과는 TBTO는 다른 수중오염원과 마찬가지로 어류 기관계의 조직병리학적 변화를 유도한다는 것을 나타낸다.