• 제목/요약/키워드: Reabsorption

검색결과 185건 처리시간 0.021초

나프록센의 항이뇨작용 기전 (Mechanism of Naproxen-Induced Antidiuretic Response in Dog)

  • 고석태;이한구;유강준
    • 약학회지
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    • 제39권3호
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    • pp.314-328
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    • 1995
  • This study was attempted to investigate the mechanism of retention of sodium and water by naproxen which is a drug among nonsteroidal anti-inflammatory drugs in dogs. Napoxen, when given intravenously in doses ranging from 30 mg to 100 mg/kg, elicited antidiuresis accompanied vath the decrease of osmolar clearance(Cosm) and amounts of sodium excreted in urine(E$_{Na}$), with the increase of sodium reabsorption rate in renal tubule(R$_{Na}$) and ratio of potassium against sodium (K/Na). Naproxen infused into a renal artery in doses ranging from 1.0mg to 3.0mg/kg/min produced both diuretic action in infused kidney and antidiuretic action in control kidney. Naproxen injected into carotid artery in doses ranging from 10.0 mg to 30.0 mg/kg exhibited antidiuretic action. Changes of renal function in the circumstances of above two antidiuresis were the same with aspect of intravenous naproxen. Antidiuretic action of naproxen injected into carotid artery was not affected by renal denervation, was blocked by pretreatment with i.v. arachidonic acid, prostaglandin precursor, or i.v. indomethacin, cyclooxygenase inhibitor. Naproxen injected into carotid artery abolished the diuretic action of i.v. spironolactone, aldosterone antagonist, and i.v. spironolactone blocked the antidiuretic action of naproxen given into carotid artery. The results suggest that naproxen produced antidiuresis, and sodium and water retention through the central system, the mechanism being related to the prostaglandin biosynthetic inhibition and aldostercfne like action.

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Clonidine이 개의 신장기능에 미치는 영향 (Influence of Clonidine on Renal Function of Dogs)

  • 고석태;김기환
    • 약학회지
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    • 제27권4호
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    • pp.271-282
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    • 1983
  • This study is an attempt to study the influence of clonidine, which has a central sympatholytic action, on the renal function in dogs and to elucidate its mechanism of action. Clonidine ($15\mu$g/kg) injected into a cephalic vein of the dog produced a marked increase in urine flow and in amounts of $Na^{+}$ and $K^{+}$ excreted in urine, and clearances of free water and osmolar substance, the reabsorption rates of $Na^{+}$ and $K^{+}$ in renal tubules were significantly decreased. Clonidine ($50.0]mu$g/kg) administered intravenouly elicited a transient reduction in urine flow, along with inhibition of all renal functions. Intravenous clonidine-induced diuretic effect was completely blocked by pretreatment with reserpine, and was lessened by water diuresis. Clonidine ($3.0\mu$g/kg) injected tnto a carotid artery revealed a transient diuresis with a increase in clearance of free water. Clonidine injected into a renal artery showed a significant antidiuretic effect and all functions of an experimental kidney were reduced. Antidiuretic action induced by clonidine given into a renal artery markedly suppressed by pretreatment with reserpine. The above results suggest that clonidine has dual mechanisms: 1) diuretic effect due to the central sympatholytic action and inhibition of release of antidiuretic hormone, and 2) antidiutetic effect indued by indirect symptheic stimulation in the periphery.

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반사 배광과 램프에 의한 반사광 흡수를 고려한 경면반사판 설계 알고리즘 개발 (Development of Specular Reflector Design Algorithm Considering Reflected Light Distribution and Light Absorption by Lamp)

  • 황재산;이정욱;김기훈;김훈
    • 조명전기설비학회논문지
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    • 제15권1호
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    • pp.7-12
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    • 2001
  • 기구 배광이 전체적인 조명환경에 미치는 영향은 크며, 기구배광은 반사판, 프리즘 설계 등으로 구현된다. 램프의 물리적 크기는 기구설계에 큰 영향을 미치기 때문에 램프에 의한 배광의 변화와 램프로 흡수되는 빛을 고려하여 기구를 설계하여야 한다. 기존의 반사파 설계 알고리즘의 경우 램프의 물리적인 크기를 고려하지 않았으며, 기구배광의 출력값도 몇몇의 경우에서는 오차가 발생하였다. 이에 본 논문에서는 램프의 크기를 고려한 반사판설계 알고리즘을 개발, 구현하여 이전의 기구설계 알고리즘이 가지고 있던 오차를 줄였으며 좋은 성과를 얻었다.

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Tight epithelia의 세포특성과 수송체계에 관한 전자현미경적 연구 (Electron Microscopic Studies on Cellular Characteristics and Transport Systems in Tight Epithelia)

  • 전진석
    • Applied Microscopy
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    • 제26권1호
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    • pp.47-57
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    • 1996
  • This study analysed the transport properties of bladder mucosa known as the typical system of 'tight epithelia' by using TEM observation with both rapid freeze-fracture electron microscopy and thin-section method and mainly analysed the cellular characteristics of turtle bladder epithelial cells. The bladder epithelium, like other tight epithelia, consists of a heterogenous population of cells. The majority of the mucosal cells are the granular cells and may function primarily in the process of active $Na^+$ reabsorption in turtle bladder. The remaining two types of cells are rich in mitochondria and is believed to be res-ponsible for a single major transport system, namely, $H^+$ transport by A-type of cell and urinary $HCO_{3}^-$ secretion by B-type of cell. As viewed in freeze-fracture electron micrograph, the tight junctions form a continuous tight seal around the epithelial cells, thus restricting diffusion in tight epithelia. In addition, the apical surface membranes have a population of rod-shaped intramembranous particles (IMPs). It is believed that these IMPs probably represent the components of the proton pump. However, it is likely that these characteristics of the apical transporter remain to be clarified in tight epithelial cells.

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Toxic Effects of Polygalae Radix on Rat Kidney

  • Yi, Eun-Young;Park, Chae-Young;Ma, Young;Lim, Dong-Koo
    • Toxicological Research
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    • 제12권1호
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    • pp.47-52
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    • 1996
  • The renal toxicity of the extract of Polygalae Radix was investigated in rats. Rats were treated with 3.5 mg/Kg of the extract, i.p., for 7 days. Changes in consumatory behavior, 24 hour-urine and the activities of urinary enzymes were determined during the administration of the extract. Significant decrease in body weight and food consumption and increase in 24 hour-urine volume were observed during the administration. However, the quantity of total creatinine in urine was decreased significantly. Those indicate that subacute treatment with the extract might induce diuresis and the ditiresis might be due to the decrease in water reabsorption. In the activities of urinary enzymes, the activities of alanine aminopejotidase (AAP) and gamma-glutamyl transpeptidase (GGT) were increased 4.3 and 3.5 times and then returned to the control. The activity of N-acetyl-${\beta}$-D-glucosaminidase (NAG) was increased 7.2 times and then decreased slowly. But, it was significantly higher than that of the control evea after the last administration. The activity of factate dehydrogenase (LDH) was increased continuozlsly during the treatment. It showed 32 times higher than the control. These results suggested that the extract of Polygalae Radix had toxic effect on kidney. Furthermore, the result suggested that the subacute administration of the extract induced resistance against the toxicity of Polygalae Radix.

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ATP 의존성 $K^+$ Channel 차단작용이 있는 Glibenclamide가 개의 신장기능에 미치는 영향 (Effects of Glibenclamide, an ATP-dependent $K^+$ Channel Blocker, on Renal Function in Dog)

  • 고석태;임광남
    • Biomolecules & Therapeutics
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    • 제7권3호
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    • pp.249-256
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    • 1999
  • Glibenclamide(GLY)(1.0 and 3.0 mg/kg), an ATP-dependent $K^+$ channel blocker, when given into the vein in dogs, produced the diuretic action accompanied with the increase of osmolar clearance($C_{osm}$), urinary excretion of $Na^+$ and $K^+$ ($E_{Na}$, $E_K$), and with the decrease in reabsorption rates for $Na^+$ and $K^+$ in renal tubules ($R_{Na}$, $R_K$), and then ratios of $K^+$ against $Na^+$($K^+$/$Na^+$) were decreased. GLY did not affect mean arterial pressure at any doses used. At a low dose(0.1 mg/kg), GLY injected into a renal artery brought about the diurectic action in both experimental and control kidney, however at a higher dose(0.3 mg/kg), GLY appeared significant diuretic action in the control kidney, but not in experimental kidney and the decrease of glomerular filtration rates(GFR), renal plasma flow(RPF), $E_K$, and the increase in $E_{Na}$. In the control kidney, these changes in renal function exhibited the same aspect as shown in intravenous experiments. In experiments given into carotid artery of GLY(0.5 and 1.5 mg/kg), changes in all renal function included the increase in urine volume were the same pattern as shown in intravenous experiments. The above results suggest that glibenclamide produces diuretic action through central function and the action site of the GLY in kidney is the renal distal tubules in dogs.

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소변의 생성, 구성성분, 색깔, 그리고 이상소견 (Overview of the Formation, Components, Color, and Abnormal Findings of Urine)

  • 박세진;신재일
    • Childhood Kidney Diseases
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    • 제17권2호
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    • pp.29-34
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    • 2013
  • Urine production is vital for the removal of certain waste products produced by metabolism in the body and for the maintenance of homeostasis in the body. The kidneys produce urine by the following three precisely regulated processes: filtration, reabsorption, and secretion. Urine is composed of water, certain electrolytes, and various waste products that are filtered out of the blood through the glomeruli. The physical features of urine are evaluated carefully to detect any abnormal findings that may indicate underlying diseases in the genitourinary system. A change in urine color may indicate an underlying pathological condition, although many of the causes of abnormal urine color are benign effects of medications and foods. A characteristic and specific odor may be the result of a metabolic disease rather than a concentrated specimen or a simple urinary tract infection. Although transient changes in urine output and nocturia are usually benign conditions, persistent abnormal findings require further workup, with a thorough medical history taking. This article presents many of the conditions that physicians may encounter and will help them in the diagnosis and in establishing a treatment plan.

Comparative study of rifampicin pharmacokinetics administered orally and intravenously in the fasted and non-fasted rats

  • Shim, Chang-Koo;Lee, Jeong-Uk
    • Archives of Pharmacal Research
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    • 제8권3호
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    • pp.177-186
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    • 1985
  • Effect of food on the absorption characteristics of oral rifampicin was studied in the fasted rats. Rifampicin dissolved in a new cosolvent was also injected to the rats intravenously, and the pharmacokinetic analysis was performed to explain the effect of food on the gastrointestinal absorption of rifampicin. Rifampicin was absorbed rapidly and completely in the fasting state. Food had a profound effect on the gastrointestinal absorption of rifampicin, i. e., bioavailability and the extent of absorption were decreased to less than one-third of the fasting state in the postprandial state. Food seemed to imhibit the absorption and reabsorption of rifampicin in the gastrointestinal tract, but not the absorption rate constant. Hepatobiliary excretion seemed to be the major route of elimination, since the renal clearance accounted for only 8 % of the systemic clearance. Nevertheless, first-pass effect was negligibly small and most of rifampicin absorbed could reach systemic circulation. Serum concentration change of oral rifampicin on multiple dosing differed markedly in the fasting and postprandial state, which suggested the need of careful adjustment of dosage regimen in both states.

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Complex open elbow fracture-dislocation with severe proximal ulna bone loss: a case report of massive osteochondral allograft surgical treatment

  • Concina, Chiara;Crucil, Marina;Theodorakis, Emmanouil;Saggin, Giorgio;Perin, Silvia;Gherlinzoni, Franco
    • Clinics in Shoulder and Elbow
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    • 제24권3호
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    • pp.183-188
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    • 2021
  • We report a case of a 69-year-old right-dominant man who had an open Monteggia-like lesion of the right elbow (Gustilo-Andersen IIIA) with severe proximal ulna bone loss associated with an ipsilateral ulnar shaft fracture due to a motorcycle accident. The patient underwent two-stage surgery. Wound debridement and bridging external fixation were performed at first. Three months later, a frozen massive osteochondral ulnar allograft was implanted and fixed with a locking compression plate. A superficial wound infection appeared 5 weeks after the second surgery. Superficial wound debridement, negative pressure therapy, and antibiotics were administered for 3 months, achieving infection healing. At 3 years post-surgery, the elbow range of motion was satisfactory with a Disabilities of the Arm, Shoulder and Hand (DASH) score of 16.7. Radiographs and computed tomography scans showed good allograft-bone integration without allograft reabsorption or hardware loosening. Although not complication-free, massive ulna osteochondral allograft implantation can be considered a valid option in cases of open Monteggia-like lesions associated with ulnar shaft fracture and severe bone loss in active patients, whenever osteosynthesis or joint replacement is not a proper solution. This type of bone stock restoration allows for future surgery, if needed.

무마취가토 신동맥내 투여에 의한 Trifluoperazine의 신장기능에 미치는 영향 (Effects of Renal Arterial Trifluoperazine on the Renal Function in Conscious Rabbit)

  • 고규영;조경우
    • The Korean Journal of Physiology
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    • 제19권1호
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    • pp.25-33
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    • 1985
  • Renal arterial infusion of renotropic agents has been a very useful technique in the renal function studies. This type of experiments have usually been conducted in the large animals such as dogs and sheep. In these animals a catheter can be placed in the site without much disturbances of renal blood flow. Rabbits as an experimental model, however, caused a disturbances of renal blood flow by a catheterization of renal artery by its properties. Therefore we have developed a new technique that allows a simple and selective access to one side of renal arteries and the other as a control, without any disturbances of renal function. The distance between the both bifurcations of renal arteries on abdominal aorta is about 7 mm. To locate the tip of catheter on one side renal artery, ascending cannulation performed via femoral artery was done. We did an experiment with the technique to clarify the effect of calmodulin inhibitor on the renal function. One of the phenothiazine derivatives, trifluoperazine known as a powerful calmodulin inhibitor. Trifluoperazine, actual dose ranges of $2.76-5.20\;ug\;{\cdot}\;kg^{-1}\;{\cdot}\;min^{-1}$, increased urine volume and glomerular filtration rate significantly. Significant increases in urinary excretion of sodium, chloride and potassium were found. Fractional excretion of sodium and free water clearance increased significantly. These data suggest that this new technique is very useful in field of renal physiology and that striking effect of trifluoperazine on the renal function may be caused by increasing the renal hemodynamics, and by the inhibition of sodium, chloride and potassium reabsorption in the renal tubules.

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