• The Korean Journal of Pharmacology
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• v.2 no.1 s.2
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• pp.13-16
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• 1966

The action of serotonin (5-Hydroxytryptamine) on the excretory function of the kidney was investigated in the dog, utilizing the clearance method and the stop-flow technique. It was shown that serotonin, $10{\mu}g/kg/min$, i. v., exerts a marked antidiuretic effects and elicits a marked hemodynamic changes in the kidney: a highly significant decrease of the glomerular filtration rate and a tendency of decrement in the renal plasma flow. Little change in the systemic blood pressure was noted, and the participation of the antidiuretic hormone in the antidiuretic action was ruled out by adding vasopressin to the infusion fluid. The stop-flow analysis showed that there is no evidence of altered activity in the tubules by serotonin. It was thus concluded that serotonin elicits anti diuresis in the dog by decreasing glomerular filtration rate, which results from the constriction of Vas afferens in the glomeruli.

• The Journal of Internal Korean Medicine
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• v.10 no.1
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• pp.125-136
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• 1989

This study was investigated to clarify the effect of Sin Bee Tang (神秘湯) on the renal function, arterial blood pressure and plasma cortisol. The results obtained were follows; 1. Urine volume and glomerular filtration rate were decreased significantly after Sin Bee Tang water extract, 0.1ml/kg, administration. 2. Glomerular filtration rate, renal plasma flow and urinary excretion of electrolytes were increased significantly after Sin Bee Tang water extract, 0.25ml/kg, administration. 3. Plasma cortisol concentration increased significantly after Sin Bee Tang water extract, 0.25ml/kg, administration. These results suggest that the therapeutic action of Sin Bee Tang for 'Su Chun (水喘)' has a relation with the increase of plasma cortisol and renal hemodynamic effect.

• Molecules and Cells
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• v.37 no.6
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• pp.435-440
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• 2014

Hemodynamic shear stress, the frictional force acting on vascular endothelial cells, is crucial for endothelial homeostasis under normal physiological conditions. When discussing blood flow effects on various forms of endothelial (dys)function, one considers two flow patterns: steady laminar flow and disturbed flow because endothelial cells respond differently to these flow types both in vivo and in vitro. Laminar flow which exerts steady laminar shear stress is atheroprotective while disturbed flow creates an atheroprone environment. Emerging evidence has provided new insights into the cellular mechanisms of flowdependent regulation of vascular function that leads to cardiovascular events such as atherosclerosis, atherothrombosis, and myocardial infarction. In order to study effects of shear stress and different types of flow, various models have been used. In this review, we will summarize our current views on how disturbed flow-mediated signaling pathways are involved in the development of atherosclerosis.

• YAKHAK HOEJI
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• v.25 no.1
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• pp.15-25
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• 1981

This study was attempted to investigate the action of debrisoquine, a sympathetic blocking agent presently employed in treating hypertension, on renal function and to elucidate the mechanism of its action. Debrisoquine, given intravenously, elicited increased urine flow, osmolar and free water clearances, along with marked increases in excretion of both sodium and potassium. Glomerular filtration rate also increased, but renal plasma flow tended to decrease, so that the filtration fraction tended to increase. Rates of reabsorption of sodium and potassium in renal tubules were also significantly diminished. The diuresis induced by debrisoquine was completely blocked by treatment with phentolamine and reserpine, and also markedly inhibited by acute renal denervation. Debrisoquine, when injected directly into a renal artery, produced antidiuretic effect and a reduction in urinary excretion of sodium and potassium, along with diminished renal plasma flow and increased filtration fraction. The above observations indicate that debrisoquine, when given intravenously, induces diuresis in the dog as a result of both diminished tubular reabsorption of electrolytes and of renal hemodynamic changes, which seem to be related to its inhibitory action of catecholamine-release from the sympathetic nerve endings.

• Korean Journal of Pharmacognosy
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• v.6 no.2
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• pp.101-110
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• 1975

In this study attempts were made to explore effects of the water and alcohol extracts of Junci Herba on the renal function of dogs. The water extract (in a dose 15 mg/kg, i.v.) and alcohol extract (in a dose 1.5 mg/kg, i.v.) elicited a diuretic response and produced a marked diuresis during bicarbonate infusion whereas no diuresis ensues during infusion of hydrochloric acid. The ratios of potassium and sodium excreted in urine $(K^+/Na^+)$, pH of urine, Cosm (osmolar clearance) and $C_{H_2O}$ (free water clearance) increased but hemodynamic states changed little with both extracts. All the observed facts can be best explained on the assumption that Junci Herba inhibits the carbonic anhydrase in the tubule. Thus it produces the effect by increasing urinary potassium and sodium.

• The Korean Journal of Pharmacology
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• v.12 no.1
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• pp.31-44
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• 1976

It has been reported that many of the effects of digitalis glycosides could be mediated partly through the central nervous system. In this study the effects of ouabain given directly into the lateral ventricle of the brain on the renal function of the rabbit were investigated. Intraventricular ouabain elicited antidiuresis in doses ranging from 0.1 to $3\;{\mu}g$, exhibiting a rough dose-response relationship, and decreased the renal plasma flow, glomerular filtration rate and urinary excretion of sodium and potassium, concomitant with the decrease of urine flow. These decreases in urine flow, excretory rate of electrolytes significantly correlated with the decrease in renal plasma flow or glomerular filtration rate, suggesting that the antidiuresis might have been induced by the hemodynamic changes. Intravenous ouabain in a dose of $1\;{\mu}g$ did not affect the renal function. Systemic blood pressure as well as cardiac activity was not affected by the intraventricular ouabain. Effects of the intraventricular ouabain on renal function were abolished by the intravenous phentolamine-pretreatment but not affected by intraventricular phentolamine-pretreatment. Neither vasopressin infusion nor hydration did affect the renal effects of intraventricular ouabain. From these observations, it is suggested that the antidiuresis of intraventricular ouabain is induced by the increased sympathetic influence to the kidney.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.752-755
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• 2009

It is well known that hemodynamic load is one of the most important determinants of cardiac structure and function. Circadian variations in blood pressure (BP) are usually accompanied by consensual changes in peripheral resistance and/or cardiac output. In recent years, reduction in circadian variations in BP and, in particular, loss of nocturnal decline of BP were observed in hypertensive patients with left ventricular hypertrophy (LVH). The patients with only a slight or no loss of nocturnal decline of BP were considered "non-dippers". Regression of LVH was observed after prolonged antihypertensive therapy. Restoration of the circadian rhythm of BP was also observed. However, the classification of patients into "dippers" and "non-dippers" is arbitrary and poorly standardized and repeatable, and in the recent studies, most hypertensive patients with LVH were "dippers". Therefore, we should be particularly cautious about the conclusions drawn using this index. On the other hand, reduced activity of low-pressure cardiopulmonary baroreceptors and impaired day-to-night modulation of autonomic nervous system activity were observed in patients with only LVH. Therefore, alterations in cardiac structure may impair BP modulation. On the other hand, the reverse can also be trueprimary alterations in BP modulation, through a persistently elevated afterload, can increase cardiac mass. Thus, the interrelationship between cardiac structure and BP modulation is complex. Hence, new and more specific methods of evaluating circadian changes in BP are needed to better clarify the abovementioned reciprocal influences.

• Journal of Pharmaceutical Investigation
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• v.14 no.2
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• pp.92-103
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• 1984

The action of debrisoquine on renal function in rabbits was studied. 1. When debrisoquine was given into ear vein, it did not affect on renal functin with smaller doses of 0.1 or 0.3mg/kg, while with higher dose of 1.0mg/kg it elicited the significant decrease of urine flow, renal plasma flow and glomerular filtration rate, and the increase of filtration fraction, and at the same time sodium excreted in urine, FENa (fractional excretion of sodium) and osmolar clearance were significantly decreased, and then it exhibited the increase of $K^+/Na^+$ ratio and no changes of $T^cH_2O$. 2. Debrisoquine (1.0mg/kg), when injected repeatedly into a vein, produced a more marked decrease of urine flow. 3. Debrisoquine induced-antidiuretic action was not affected by pretreatment with phentolamine (2mg/kg, i.v.), alpha-sympathetic blocking agent. 4. Debrisoquine given intracerebroventricularly did not produce a significant change on renal function in dose of 0.1mg/kg. These results suggest that debrisoquine produce the antidiuretic effect in rabbit, and the mechanism of its action is due to dual actions that are the decrease of hemodynamic effect and the facilitation of reabsorption of sodium in renal tubules.

• Journal of Veterinary Clinics
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• v.18 no.4
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• pp.358-362
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• 2001

Brain dead (BD) patients remain the largest source of solid organs for transplantation. BD has shown to decrease graft function and survival in rodent models. The aim of this study was to evaluate how brain death affects graft viability in the donor and kidney tolerance to cold preservation as assessed by survival in a canine transplantation. 13 Beagle dogs were used for the study. Brain death was induced by the sudden inflation of a subdural balloon catheter with continuous monitoring of arterial blood pressure and eletroencephalographic activity (n=3). Sixteen hours after conformation of brain death, kidney graft were retrieved (n=6). Non-BD donors served as controls (n=4). All kidneys were flushed with University of Wisconsin (UW) solution and preserved for 24 hours at 4$^{\circ}C$ before transplantation. Recipient survival rates, serum creatinine level were analyzed. Brain death induced the well-known Cushing reaction with a severe increase in blood pressure and tachycardia. Thereafter, cardiac function returned progressively to baseline within 8 hours and remained stable until the end of the experiment. All of dogs in both group transplanted were survived until 7 days (100%), and the kidneys showed functional early rejection at 8.3$\pm$0.5 days and 8.5$\pm$0.5 days after transplantation, in BD and allograft group, respectively. BD kidneys were functionally similar to control kidneys for 7 days after transplantated. Brain death has no deleterious effect on preservation injury and survival of dog kidney transplantation, although it induces changes in hemodynamic parameters. This study reveals that kidneys from BD donors do not exhibit more ischemia reperfusion injury, and support good early function and survival.

• Journal of Chest Surgery
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• v.32 no.3
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• pp.224-236
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• 1999

Background: To evaluate the short-term effect of dynamic cardiomyoplasty on circulatory function and detect the related factors that can affect it, experimental cardiomyoplasties were performed under the state of normal cardiac function and heart failure. Material and Method: A total of 10 mongrel dogs weighing 20 to 30kg were divided arbitrarily into two groups. Five dogs of group A underwent cardiomyoplasty with latissimus dorsi(LD) muscle mobilization followed by a 2-week vascular delay and 6-week muscle training. Then, hemodynamic studies were conducted. In group B, doxorubicin was given to 5 dogs in an IV dose of 1 mg/kg once a week for 8 weeks to induce chronic heart failure, and simultaneous muscle training was given for preconditioning during this period. Then, cardiomyoplasties were performed and hemodynamic studies were conducted immediately after these cardiomyoplasties in group B. Result: In group A, under the state of normal cardiac function, only mean right atrial pressure significantly increased with the pacer-on(p<0.05) and the left ventricular hemodynamic parameters did not change significantly. However, with pacer-on in group B, cardiac output(CO), rate of left ventricular pressure development(dp/dt), stroke volume(SV), and left ventricular stroke work(SW) increased by 16.7${\pm}$7.2%, 9.3${\pm}$3.2%, 16.8${\pm}$8.6%, and 23.1${\pm}$9.7%, respectively, whereas left ventricular end-diastole pressure(LVEDP) and mean pulmonary capillary wedge pressure(mPCWP) decreased by 32.1${\pm}$4.6% and 17.7${\pm}$9.1%, respectively(p<0.05). In group A, imipramine was infused at the rate of 7.5mg/kg/hour for 34${\pm}$2.6 minutes to induce acute heart failure, which resulted in the reduction of cardiac output by 17.5${\pm}$2.7%, systolic left ventricular pressure by 15.8${\pm}$2.5% and the elevation of left ventricular end-diastole pressure by 54.3${\pm}$15.2%(p<0.05). With pacer-on under this state of acute heart failu e, CO, dp/dt, SV, and SW increased by 4.5${\pm}$1.8% and 3.1${\pm}$1.1%, 5.7${\pm}$3.6%, and 6.9${\pm}$4.4%, respectively, whereas LVEDP decreased by 11.7${\pm}$4.7%(p<0.05). Comparing CO, dp/dt, SV, SW and LVEDP that changed significantly with pacer-on, both under the state of acute and chronic heart failure, augmentation widths of these left ventricular hemodynamic parameters were significantly larger under the state of chronic heart failure(group B) than acute heart failure(group A)(p<0.05). On gross inspection, variable degrees of adhesion and inflammation were present in all 5 dogs of group A, including 2 dogs that showed no muscle contraction. No adhesion and inflammation were, however, present in all 5 dogs of group B, which showed vivid muscle contractions. Considering these differences in gross findings along with the following premise that the acute heart failure state was not statistically different from the chronic one in terms of left ventricular parameters(p>0.05), the larger augmentation effect seen in group B is presumed to be mainly attributed to the viability and contractility of the LD muscle. Conclusion: These results indicate that the positive circulatory augmentation effect of cardiomyoplasty is apparent only under the state of heart failure and the preservation of muscle contractility is important to maximize this effect.