• The Korean Journal of Physiology
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• v.22 no.2
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• pp.319-332
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• 1988

The regulations of renal function and renin release are influenced by neural, humoral and physical factors. During the last decade, considerable progress has been made in the identification and characterization of these extrinsic renal control systems. Mechanisms intrinsic to the kidney are also important for renal function. These include the autoregulation of blood flow, and the local control of renin secretion. Fundamental questions regarding the mechanism of these intrinsic controls remain unanswered. Recently, endogenous renal adenosine has been claimed to influence the tubuloglomerular feedback control and renin release. Two subclasses of adenosine receptors $A_1{\;}and{\;}A_2$ have been described. The present experiment was carried out to evaluate the effects of $N_6-cyclohexyladenosine$ $(CHA,{\;}A_1{\;}selective)$ and 5'-N-ethylcarbox-amide adenosine $(NECA,{\;}A_2{\;}selective)$ on the renal function and renin release in the unanesthetized rabbit. Intra-renal arterial infusion of NECA $(0.3{\sim}10.0n{\;}mole/min/rabbit)$ or CHA $(0.03{\sim}10.0n{\;}mole/min/rabbit)$ caused a prompt and dose-dependent decrease in urine volume, glomerular filtration rate (GFR), renal plasma flow (RPF), filtration fraction (FF), electrolyte excretion and free water clearance $(CH_2O)$, the effect being much more profound with CHA than with NECA. The NECA infusion resulted in a profound decrease of systemic blood pressure, but the CHA infusion did not. Both NECA and GHA infusions caused a prompt and dose-dependent decrease in renin secretion rate, again the effect being greater with CHA than with NEGA. These results suggest that both $A_1{\;}and{\;}A_2$ adenosine receptors may be involved in the intrinsic control of renal function and renin release, and that the $A_1$ receptors plays a more important role than the $A_2$ receptor in the regulation of renal fnction.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.5
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• pp.555-563
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• 1998

The renal function is under regulatory influence of central nervous system (CNS), in which various neurotransmitter and neuromodulator systems take part. However, a possible role of central GABA-benzodiazepine system on the central regulation of renal function has not been explored. This study was undertaken to delineate the renal effects of diazepam. Diazepam, a benzodiazepine agonist, administered into a lateral ventricle (icv) of the rabbit brain in doses ranging from 10 to 100 ${\mu}g/kg,$ elicited dose-related diuresis and natriuresis along with improved renal hemodynamics. However, when given intravenously, 100 ${\mu}g/kg$ diazepam did not produce any significant changes in all parameters of renal function and systemic blood pressure. Diazepam, 100 ${\mu}g/kg$ icv, transiently decreased the renal nerve activity (RNA), which recovered after 3 min. The plasma level of atrial natriuretic peptide (ANP) increased 7-fold, the peak coinciding with the natriuresis and diuresis. Muscimol, a GABAergic agonist, 1.0 ${\mu}g/kg$ given icv, elicited marked antidiuresis and antinatriuresis, accompanied by decreases in systemic blood pressure and renal hemodynamics. When icv 0.3 ${\mu}g/kg$ muscimol was given 3 min prior to 30 ${\mu}g/kg$ of diazepam icv, urinary flow and Na excretion rates did not change significantly, while systemic hypotension was produced. These results indicate that icv diazepam may bring about natriuresis and diuresis by influencing the central regulation of renal function, and that the renal effects are related to the increased plasma ANP levels, not to the decreased renal nerve activity, and suggest that the effects may not be mediated by the activation of central GABAergic system.

• The Korean Journal of Nuclear Medicine
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• v.24 no.1
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• pp.119-123
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• 1990

Unexpected renal abnormality can be detected on bone scan using Tc-99m-MDP. The purpose of the study is to evaluate the diagnostic significance of diffusely increased bliateral renal uptake on bone scarf. 1,500 boor scan were reviewed and 43 scans which showed diffusely increased bliateral renal uptake were selected for analysis. Laboratory findings for renal and liver function tests including routine urinalysis were reviewed in 43 patients. 26 of 43 case showed abnormality in urinalysis and renal function stud 20 of 43 cases showed abnormal liver function study and 3 of these cases were diagnosed as hepatorenal syndrome later. 13 of those 20 cases had liver cirrhosis with or without hepatoma. 12 of 43 cases showed abnormality both in renal and liver function studies. 2 of 43 cases showed diffusely increased bilateral renal uptake after chemotherapy for cancer but not on previous scans before chemotherapy. 2 of 43 cases showed hypercalcemia and 8 of 43 cases had multifocal bone uptake due to metastasis or benign bone lesion. but the latter showed no hypercalcemia at all. There was no significant correlatrion between increased renal uptake and MDP uptake in soft tissue other than kidneys. This study raised the possibility that the impaired liver and/or renal function may result in diffuse increase of bliateral renal uptake of MDP of unknown mechaninsm. It seems to need further study on this correlation.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.4
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• pp.427-434
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• 1999

This study was conducted to investigate the effects of vitamin I supplementation on renal function in high fat diet and adriamycin (ADR) induced experimental nephrotic syndrome in model rats. The effects of vitamin E supplementation on renal function in high fat diet and ADR treated rats were as follows. Kidney weight was decreased by vitamin E supplementation. Serum total protein was increased by the excess supplementation. Blood urea nitrogen(BUN) was decreased by the high supplementation. However, serum albumin and creatinine showed no significant differences between groups. Urinary volume tended to increase by vitamin I supplementation. Urinary urea-N tended by vitamin I supplementation. Particularly glomerular filtration rate(GFR) was significantly decreased by vitamin E supplementation. These results suggested that vitamin E supplementation could alleviate the adverse effects caused in renal function by highfatdiet and ADR treatments.

• 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.

• YAKHAK HOEJI
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• v.26 no.4
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• pp.197-208
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• 1982

In this study attemps were made to obtain evidence as to the action of Mori Radicis Cortex on the renal' function of anesthetized mongrel dogs. 1. A light brown powder isolated from Mori Radicis Cortex (MRC) by a slight modification of Tanemura's method, when given intravenously in doses ranging 0.5 to 5.0mg/kg, elicited diuresis with the increase of positive water clearance and amounts of $Na^{+}$ and $K^{+}$ excreted in the urine. At this time the glomerular filtration rate, renal plasma flow and osmolar clearance were not observed to have any significant changes. This diuresis was augmented in process of time and its maximum effect was exhibited about 30 minutes after administration of MRC. 2. The MRC, when administered into a intra carotid artery, responded promptly with diuresis and natriuresis at a level too small to effect renal functions when administered intravenously. In this experiment the patterns of changes of renal function were the patterns of changes of renal function were the same as those of the above intravenously administered experiment. 3. When infused directly into a renal artery, the MRC exhibited little effect on either kidney. 4. During water diuresis, the MRC did not elicit diuretic action or significant changes in renal functions. The above observations suggest that the diuresis of MRC is brought about by the inhibition of the release of antidiuretic hormone with the mechanism facilitating the excretion of $Na^{+/}$ and $K^{+}$ in urine.

• Clinical and Experimental Pediatrics
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• v.61 no.11
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• pp.339-347
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• 2018

Acute kidney injury (AKI) is characterized by abrupt deterioration of renal function, and its diagnosis relies on creatinine measurements and urine output. AKI is associated with higher morbidity and mortality, and is a risk factor for development of chronic kidney disease. There is no proven medication for AKI. Therefore, prevention and early detection are important. Physicians should be aware of the risk factors for AKI and should monitor renal function in high-risk patients. Management of AKI includes optimization of volume status and renal perfusion, avoidance of nephrotoxic agents, and sufficient nutritional support. Continuous renal replacement therapy is widely available for critically ill children, and this review provides basic information regarding this therapy. Long-term follow-up of patients with AKI for renal function, blood pressure, and proteinuria is recommended.

• Korea-Australia Rheology Journal
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• v.17 no.3
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• pp.117-123
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• 2005

Background: Reduced deformability of red blood cells (RBCs) may play an important role on the pathogenesis of chronic vascular complications of diabetes mellitus. However, available techniques for measuring RBC deformability often require washing process after each measurement, which is not optimal for day­to-day clinical use at point of care. The objectives of the present study are to develop a device and to delineate the correlation of impaired RBC deformability with diabetic nephropathy. Methods: We developed a disposable ektacytometry to measure RBC deformability, which adopted a laser diffraction technique and slit rheometry. The essential features of this design are its simplicity (ease of operation and no moving parts) and a disposable element which is in contact with the blood sample. We studied adult diabetic patients divided into three groups according to diabetic complications. Group I comprised 57 diabetic patients with normal renal function. Group II comprised 26 diabetic patients with chronic renal failure (CRF). Group III consisted of 30 diabetic subjects with end-stage renal disease (ESRD) on hemo-dialysis. According to the renal function for the diabetic groups, matched non-diabetic groups were served as control. Results: We found substantially impaired red blood cell deformability in those with normal renal function (group I) compared to non-diabetic control (P = 0.0005). As renal function decreases, an increased impairment in RBC deformability was found. Diabetic patients with chronic renal failure (group II) when compared to non-diabetic controls (CRF) had an apparently greater impairment in RBC deformability (P = 0.07). The non-diabetic cohort (CRF), on the other hand, manifested significant impairment in red blood cell deformability compared to healthy: control (P = 0.0001). Conclusions: The newly developed slit ektacytometer can measure the RBC deformability with ease and accuracy. In addition, progressive impairment in cell deformability is associated with renal function loss in all patients regardless of the presence or absence of diabetes. In diabetic patients, early impairment in RBC deformability appears in patients with normal renal function.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.683-693
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• 2001

This study was attempted to investigate the effect of raclopride, a dopamine $D_2$ receptor antagonist, on renal function in dog. Raclopride (70-220$\mu\textrm{g}$/kg), when given intravenously, Produced antidiuresis along with the decrease in free water clearance ( $C_{H_2O}$), urinary excretion of sodium and potassium ( $E_{Na}$ , $E_{K}$), partially decreased osmolar clearance ( $C_{osm}$) and increased reabsorption rates of sodium and potassium in renal tubules ( $R_{Na}$ , $R_{K}$). Raclopride administered into a renal artery did not influence on renal function in small doses (10 and 30$\mu\textrm{g}$/kg), whereas exhibited the decrease of urine volume (Vol) and $C_{H_2O}$ both in experimental and control kidney in much dose (100$\mu\textrm{g}$/kg), at this time, the decreased rates of both Vol. and $C_{H_2O}$) were more prominent in control kidney rather than that elicited in experimental kidney, and then only via was decreased in control kidney but increased in experimental kidney. Raclopride administered via carotid artery (30-200$\mu\textrm{g}$/kg) did not influence at all on renal function. Antidiuretic action induced by raclopride given intravenously was not affected by renal denervation. Raclopride given into carotid artery was little effect on renal function without relation to renal denervation. Above results suggest that raclopride produces antidiuresis by potentiation of antidiuretic hormone (ADH) action in blood without increase of ADH secretion in posterior pituitary gland, it is not related to renal nerve function in dogs.ogs.s.

• The Korean Journal of Physiology
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• v.19 no.1
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• pp.35-48
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• 1985

One of most frequently used anesthetic agents is barbiturate derivatives. Pentobarbital or thiopental sodium have been used most frequently in the laboratory or clinical practice. There have been reports on the renal effects of barbiturate anesthesia in human and laboartory animals. Renal effects of thiopental sodium anesthesia, however, are still controversial. One of the discrepancies may be derived from the doses used. It has been reported that subanesthetic small dose of thiopental sodium influences the renal function directly. To clarify possible central effects of very small amounts of thiopental sodium on the renal function, experiments have been done in conscious rabbits. Thiopental sodium was infused into the lateral cerebroventricle for 10 minutes. Intracerebroventricular thiopental sodium induced increased urinary volume, glomerular filtration rate and renal plasma flow by doses of $0.1{\sim}1.0\;mg/10 min/rabbit$. Filtration fractions were not changed. Sodium, chloride and potassium excretions were increased by 0.065 mg/10 min/rabbit of thiopental sodium without significant changes of renal hemodynamics. Higher doses of thiopental sodium $(0.1{\sim}1.0\;mg/10 min/rabbit)$ induced greater increases of electrolytes excretion and renal hemodynamics. Free water clearance was not changed by thiopental sodium, but the fractional excretion of free water showed a tendency of decrease. Fractional excretion of sodium was increased by doses of 0.065 to 1.0 mg of thiopental sodium . Highly significant correlation between the changes of glomerular filtration rate and the changes of sodium excretion were found in the higher doses. Plasma renin concentration (activity) was not changed by the centrally administered thiopental sodium. Intravenous thiopental sodium, 1.0 mg/rabbit, induced no changes of renal function in conscious rabbit. These data suggest that intracerebroyentricular thiopental sodium can increase urinary sodium excretion directly by inhibition of sodium reabsorption in the renal tubules and/or indirectly by increasing the renal hemodynamics.