• Title/Summary/Keyword: Distal tubule

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Effect of Bradykinin on Oxygen Consumption in the Distal Tubule and Cortical Collecting Tubule of Rat (흰쥐 원위세뇨관과 피질집합관의 산소소비량에 대한 Bradykinin의 영향)

  • Lee, Seok-Yong;Cho, Kyu-Chul
    • The Korean Journal of Pharmacology
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    • v.26 no.2
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    • pp.161-166
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    • 1990
  • Infusion of bradykinin (BK) into the renal arteries increases sodium excretion. However, it is not clear whether natriuresis results from the renal hemodynamic effects or from the direct effect on renal tubular sodium transport. Therefore, we examined the effects of BK on the transport-dependent oxygen consumption in the distal tubule (DT) and cortical collecting tubule (CCT) of deoxycorticosterone-treated rats. BK inhibited oxygen consumption in a dose-dependent way with a maximal reduction at $0.1\;{\mu}M$ BK. The inhibitory effect of BK was not present in the absence of sodium or in the presence of ouabain (1 mM). These data imply that the inhibitory effect of BK is restricted to the sodium transport-dependent oxygen consumption. We also investigated the relationship between the effect of BK on oxygen consumption and arachidonic acid metabolism. Mepacrine $(10\;{\mu}M)$, an inhibitor of membrane phospholipases, prevented the inhibitory effect of BK, but indomethacin (0.5 mM) didn't. These results suggest that BK decreases the sodium transport-related oxygen consumption in the rat DT and/or CCT, and that it may be mediated by products of enzymes other than cyclooxygenase.

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Renal Tubular Acidosis (신세뇨관 산증)

  • Park, Hye-Won
    • Childhood Kidney Diseases
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    • v.14 no.2
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    • pp.120-131
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    • 2010
  • Renal tubular acidosis (RTA) is a metabolic acidosis due to impaired excretion of hydrogen ion, or reabsorption of bicarbonate, or both by the kidney. These renal tubular abnormalities can occur as an inherited disease or can result from other disorders or toxins that affect the renal tubules. Disorders of bicarbonate reclamation by the proximal tubule are classified as proximal RTA, whereas disorders resulting from a primary defect in distal tubular net hydrogen secretion or from a reduced buffer trapping in the tubular lumen are called distal RTA. Hyperkalemic RTA may occur as a result of aldosterone deficiency or tubular insensitivity to its effects. The clinical classification of renal tubular acidosis has been correlated with our current physiological model of how the nephron excretes acid, and this has facilitated genetic studies that have identified mutations in several genes encoding acid and base ion transporters. Growth retardation is a consistent feature of RTA in infants. Identification and correction of acidosis are important in preventing symptoms and guide approved genetic counseling and testing.

Effect of Diltiazem on Renal Function in the Dog (딜티아젬의 개 신장기능에 미치는 영향)

  • Ko, Suk-Tai;Lim, Kwang-Nam
    • YAKHAK HOEJI
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    • v.38 no.5
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    • pp.568-578
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    • 1994
  • This study was performed in order to investigate the effect of diltiazem, which is a $Ca^{2+}$ channel blocker of benzothiazepine derivatives, on renal function in the dog. Diltiazem, when infused into the vein or carotid artery, produced the antidiuresis accompanied with the decreased excretion rates of sodium and potassium in urine$(E_{Na},\;E_K)$ and the increased reabsorption rates of sodium and potassium in renal tubules$(R_{Na},\;R_K)$. Diltiazem, when infused into a renal artery, exhibited the diuresis along with the increased renal plasma flow(RPF), osmolar clearance$(C_{osm})$, $E_{Na}$ and $E_K$, and decreased $R_{Na}$ and $R_K$ in only infused kidney. Above results suggest that diltiazem possess both antidiuretic action through central action and diuretic action by direct inhibition of electrolytes reabsorption rates in renal tubules, mainly distal tubule.

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Changes of Glycosylation Pattern in Aging Rat Kidneys as Revealed with Lectin Conjugates (성장과정 중 흰쥐 신장의 복합당질 변화에 대한 연구)

  • Gil, Young-Gi;Kim, Keun-Ha;Choi, Byung-Tae
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1347-1353
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    • 2007
  • The changes of glycoconjuagates (GCs) in rat kidney due to maturation were studied from samples of fetal and postnatal kidneys by lectin histochemistry. Rat kidneys of perinatal ages and adults were fixed in 4% paraformaldehyde and were stained with nine kinds of biotinylated lectins. The immature forms of the renal developmental stage such as vesicles and ureteric bud were observed in the cortex as late as day 14 of postnatal life, but the histological appearance of the weaning kidney was similar to that observed in adults. As for histochemical properties of GCs in the glomeruli, Con A affinity tended to increase with aging, but both RCA-1 and LCA affinities showed a transient increase in immature glomeruli of neonatal rats. DBA affinity with SBA, PNA, BSL-1 and RCA-1, additional Con A one in proximal tubule, were increased in both proximal and distal tubules according to maturation. In contrast to this, transient intensive LCA affinity were demonstrated in immature proximal and distal tubule of neonatal rats. In the collecting tubules, DBA, SBA, PNA and sWGA affinities tended to increase according to maturation, but transient increase for BSL-1, RCA-1 and LCA affinities were detected in neonatal rats. The present results suggest that the mature glycosylation pattern of the kidney undergoes profound changes during maturation and is probably associated with functional maturation of the kidney.

Effects of Jinmootang on the Gentamicin-induced Nephrotoxicity in Rats (진무탕(眞武湯)이 Gentamicin-유도 신독성에 미치는 영향)

  • Lee, Kyu-Hyun;Kim, Gil-Whon
    • Journal of Oriental Physiology
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    • v.14 no.2 s.20
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    • pp.189-198
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    • 1999
  • Aminoglycosides, including gentamicin, have been used as antibiotics for the various infections by gram-negative bacteria. However, there are some restrictions for using these drugs. Gentamicin, a typical aminoglycoside, has the side effect of nephrotoxicity, including polyuria, glycosuria, proteinuria, glomerulonephritis, and uremia. The aims of this study were to examine the prevention or reduction effects of Jinmootang on the gentamicin-induced nephrotoxicity and to investigate the possible mechanisms on the effect of Jinmootang. The subcutaneous injections of 60mg of gentamicin per kg of boby weight to Sprague-Dawley rats for 8 days induced typical symptoms of nephrotoxicity by aminoglycosides. 0.6ml of water extract Jinmootang (100ml/chup) was orally treated in the experimental animal. 24-hour urine was collected with the metabolic cage and plasma was sampled from the abdominal aorta. The plasma concentration of sodium was significantly decreased by the treatment of gentamicin but it was not-significantly changed by the treatment of Jinmootang to the animal. The concentration of potassium was greatly decreased in the gentamicin-treated animals. However. it was returned to the normal level in the Jinmootang-treated animals. The concentrations of creatinine and urea were increased by gentamicin treatment. But, Jinmootang reduced these concentrations. Nevertheless, the osmolalities of plasma in both group were not different from each other. Even though the plasma concentration of aldosterone was not significantly changed, the mean value was increased by the gentamicin intoxication. The concentration of aldosterone was decreased by the treatment of Jinmootang. The reduction of aldosterone level in plasma could be a factor to improve the hypokalemia. The fractional excretion of potassium was much higher than normal by the treatment of gentamicin and it was decreased by 50% in the Jinmootang-treated rats. Therefore, the reabsorption of potassium was significantly increased by the treatment of Jinmootang, even though the filtered load of potassium in the experimental group was much highter than control. Even though the concentration of plasma aldosterone was decreased by the treatment of Jinmootang, the fractional excretion of sodium was not increased, slightly lower. These data suggested that Na reabsorption was increased in the proximal tubule by Jinmootang. The filtered load of glucose in the Jinmootang-treated group was greater than in control. Nevertheless, the fractional excretion of glucose in the experimental group was not different from that in control. These results indicate that glucose reabsorption was increase in the proximal tubule by Jinmootang treatment. The results of this study suggest that Jinmootang could improve the some nephrotoxic symptoms induced by gentramicin treatment. Hypokalemia, the reduced glomerular filtration rate, and dysfunctions of renal proximal tubule and distal nephron were significantly recovered to normal level. The increase of glomerular filtration rate by Jinmootang might contribute to eliminate the waste product, including creatinine and urea, and/or gentamicin through the kidney.

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Rheumatoid arthritis accompanied by Gitelman syndrome (류마티스관절염 환자에 동반된 Gitelman 증후군)

  • Park, Min Gi;Lee, Ji Hyun;Kim, Sung Jun;Park, Su Ho;Park, Suk Ki;Choi, Joon Sul;Hwang, Ji Yeon
    • Journal of Yeungnam Medical Science
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    • v.34 no.1
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    • pp.101-105
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    • 2017
  • Gitelman syndrome is a condition caused by a mutation of the thiazide sensitive Na-Cl cotransporter gene on the distal convoluted tubule. It results in a variety of clinical features, including hypokalemia, hypomagnesemia, hypocalciuria, and metabolic alkalosis. It is often diagnosed in asymptomatic adults presented with unexplained hypokalemia; however, it is sometimes associated with muscular cramps, numbness, fatigue, weakness, or paralysis. We experienced a case of rheumatoid arthritis accompanied by Gitelman syndrome, presented with hand tremor. We diagnosed her using renal clearance study and genetic analysis. Here, we report our experiences regarding this case along with a literature review.

Renal Handling of Sodium and Potassium in Cadmium Exposed Rats

  • Kim, Yung-Kyu;Park, Yang-Saeng
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.4
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    • pp.503-510
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    • 1998
  • Effects of cadmium exposure on renal $Na^+$ and $K^+$ transports were studied in rats. During the course of cadmium treatment (2 mg Cd/kg/day, s.c. injections for 3 weeks) renal tubular transports of $Na^+$ and $K^+$ were evaluated by lithium clearance technique. During the early phase (first week) of cadmium treatment, urinary $Na^+$ excretion decreased drastically and this was due to an increased $Na^+$ reabsorption both in the proximal and distal nephrons. During the late phase (third week) of cadmium treatment, filtered $Na^+$ load was decreased by reduction in GFR, but the renal $Na^+$ excretion returned to the control level due to impaired $Na^+$ transport in the proximal tubule. Urinary excretion of $K^+$ did not change during the early phase, but it rose markedly during the late phase of cadmium treatment. These results indicate that a light cadmium intoxication induces a $Na^+$ retention, and a heavy intoxication results in a $K^+$ loss. Possible mechanisms for these changes are discussed.

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Renal Action of TNPA, a Dopamine $D_2$Receptor Agonist, in Dog (Dopamine $D_2$Receptor 효능제인 TNPA의 신장작용)

  • 고석태;황명성
    • YAKHAK HOEJI
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    • v.45 no.2
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    • pp.205-213
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    • 2001
  • The dopaminergic receptors were consisted of two distinct subtypes, $D_1$and $D_2$, each having different function. The present study was attempted to investigate the effects of R(-)-2,10,11-trihydroxy-N-n-propylnoraporphine (TNPA), a dopamine $D_2$receptor agonist, on renal function in dog. TNPA (5.0~15.0 $\mu$g/kg), when given into the vein, produced a dose-dependently antidiuresis along with the decrease in osmolar clearance ( $C_{osm}$) and urinary excretion of sodium and potassium ( $E_{Na}$ , and $E_{K}$). It also increased reabsorption rates of sodium and potassium in renal tubules ( $R_{Na}$ , $R_{K}$) without any changes in glomerular filtration rate (GFR), renal plasma flow (RPF) and free water clearance ( $C_{H2o}$). TNPA (0.5~1.5 $\mu$g/kg/min) infused into a renal artery decreased urine flow both in the experimental and the control kidneys. TNPA (1.5~5.0 $\mu$g/kg) administered via the carotid artery also greatly exhibited antidiuresis even at intravenously ineffective doses. Changes of renal function by TNPA given into both the renal artery and the carotid artery were almost the same aspect to those induced by intravenous TNPA. These results obtained from the present study suggest that TNPA produces antidiuresis by increasing the reabsorption rates of electrolytes in renal tubules, mainly distal tubule, through changing of central function.unction.

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Two Cases of Gitelman's Syndrome Diagnosed by Renal Clearance Study (신장청소검사를 이용하여 진단한 Gitelman 증후군 2례)

  • Kim, Tae Hwa;Kim, Seung Jun;Seo, Yu Kyung;Shim, Jung-Yeon;Jung, Hye Lim;Park, Moon Soo;Kum, Dong Hyuk
    • Clinical and Experimental Pediatrics
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    • v.45 no.3
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    • pp.413-417
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    • 2002
  • Gitelman's syndrome is an autosomal recessive disorder characterized by hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalciuria that has recently been reported to be linked to thiazide- sensitive Na-Cl cotransporter gene mutation. In this study, we performed renal clearance studies to differentiate Gitelman's from Bartter's syndrome and to confirm the diagnosis in two patients clinically diagnosed with Gitelman's syndrome. Each patient was hydrated by 20 mL/kg body weight of oral water within 30 minutes, which was followed by intravenous half saline. When urinary flow reached 10 mL/min, samples of urine and serum were obtained to calculate the osmolar clearance, free water clearance, chloride clearance, and distal fractional chloride reabsorption. Subsequently, furosemide or hydrochlorothiazide was administered. Samples were collected and the same parameters were calculated. In our patients, chloride clearance was increased more than 10 times after furosemide administration(2.1 : 25.7 and 2.2 : 27.4 mL/min/100 mL GFR), but not increased after hydrochlorothiazide treatment(2.1 : 1.6 and 2.2 : 2.6 mL/min/100 mL GFR). And the distal fractional chloride reabsorption was significantly decreased by furosemide injection (73% : 15% and 75% : 4.6%), whereas hydrochlorothiazide had no effect on it(73% : 63% and 75% : 78%). These findings indicate that our patients have a defect in thiazide-sensitive Na-Cl cotransporter in the distal tubule, which is compatible with the pathophysiology of Gitelman's syndrome.

Treatment of Primary Hypertension by Oryung-san Monotherapy: a Case Report (오령산 단일 투여를 통한 일차성 고혈압 치험례)

  • Jang, In-Soo;Kim, Min-Ji;Han, Hyun-Jin;Jeong, Min-Jeong;Kang, Sei-Young
    • The Journal of Internal Korean Medicine
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    • v.35 no.1
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    • pp.106-110
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    • 2014
  • Objectives : To report a case of the treatment of primary hypertension by Oryung-san (五苓散: Wulingsan in Chinese, Goreisan in Japanese) monotherapy. Methods : The blood pressure (BP) fluctuation was checked of a woman who had sudden BP elevation without a history of hypertension treatment. There were no specific history of disease and results for the laboratory examination and image diagnosis including MRI. The woman was diagnosed with primary hypertension and she was given supple of Oryung-san extract (Hanpoong Pharm Co.) 3 g, three times a day for three months. The BP has been checked with digital sphygmomanometer (HEM-7111, Omron Japan) in brachial artery at home. Results and Conclusions : The patient had had stable BP since three weeks after Oryung-san treatment was initiated. There were no subjective symptoms, then Oryung-san medication also had quit after three months treatments. This shows some possibility to control hypertension using Oryung-san, which resembles thiazide that acts on the distal convoluted tubule and inhibit sodium-chloride reabsorption. For further evaluation of the effectiveness, well-designed randomized controlled trials should be undertaken.