No abstract available.
Anesthesia* ; Renal Circulation*

In this study, effects of the intraventricular and intravenous dimethylphenylpiperazinium (DMPP) on the renal function of rabbits were investigated. Intraventricular DMPP (100 microgram) elicited diuresis following antidiuresis concomitant with the changes in renal blood flow, glomerular filtration rate and urinary excretory amount of electrolytes (Na and K). The changes in urine flow correlated with the changes in renal blood flow, glomerular filtration rate and excretory rates of electrolytes in urine. Intravenous DMPP (50 microgram/kg) did not affect the renal function.
Dimethylphenylpiperazinium Iodide ; Diuresis ; Electrolytes ; Glomerular Filtration Rate ; Rabbits* ; Renal Circulation

In an attempt to obtain evidence in the mechanism of stone formation, the effectiveness of Amiloride. a K-sparing diuretic known to act on the distal nephron. on the kidney with oxamide-induced urolithiasis was investigated. Futhermore. the influence of stone formation on the distribution of intrarenal blood flow and the effect of Amiloride on them were also studied. Most prominent derangements of renal function observed during stone formation were decreases of both C(PAH) and C(cr) indicating the curtailment in renal hemodynamics. The oxamide-treated kidney also responded to Amiloride with typical natriuresis and antikaluresis. in the same fashion with normal kidneys. The experiments in which the intrarenal blood flow distribution was measured by PAH-extraction technique raveled that mainly the cortical blood flow was curtailed, whereas non-cortical blood flow (medullary flow) did not change during oxamide-stone formation. Amiloride did not influence the intrarenal b100d flow distribution both in normal and oxamide kidneys. These observations suggest that oxamide-stone formation was initiated not by tubular necrosis produced by the toxic action of oxalate on the tubules, but rather by mechanical obstruction of the tubules.
Amiloride* ; Hemodynamics ; Kidney* ; Natriuresis ; Necrosis ; Nephrons ; Renal Circulation ; Urolithiasis

Renal blood flow was measured by single injection technique of HippuranI13 in 13 patients with chronic glomerulonephritis and 11 control subjects. There was a significant decrease in renal blood flow in chronic glomerulonephritis particulary in those with elevated blood urea nitrogen. Renal blood flow was inversely proportionate to renal vascular resistance but no correlation was noted between renal blood flow and creatinine clearance.
Blood Urea Nitrogen ; Creatinine ; Glomerulonephritis* ; Humans ; Renal Circulation* ; Vascular Resistance

Aiming at the current situation of performance testing of hemodialysis extracorporeal circulation tubing, which has slow efficiency, inaccurate measurement, and inconvenient testing, a portable detection system for testing the performance of hemodialysis extracorporeal circulation tubing is designed. The system mainly includes a hardware system and a software system. The hardware system uses STM32F407 single-chip microcomputer as the core to design the driving control of the roller pump; the software system uses the C++ real-time operating system, and the flow detection data is transmitted to the upper computer through RS485 communication and displayed. Experimental showed that the system detects the accuracy and the stability of the flow rate. It has the characteristics of stability and high precision. The relative error of the experimental measurement is within the range of ±10%. The weight of the whole machine is 2 kg, which improves the efficiency by 50% compared with the traditional detection method.
Computers ; Equipment Design ; Extracorporeal Circulation ; Microcomputers ; Renal Dialysis ; Software

Acute nonmyoglobinuric renal failure with severe loin pain and patchy renal vasoconstriction is a clinical syndrome that occurs following exercise in previously healthy young persons. Also nonsteroidal anti-inflammatory drugs predispose to acute renal failure in conditions associated with decreased renal blood flow. Probably exercise-induced renal ischemia and prostaglandin inhibition by NSAIDs may predispose to develop this syndrome. Here, we report two cases of acute renal failure with severe loin pain after strenuous exercise while taking NSAIDs with review of literature.
Acute Kidney Injury* ; Anti-Inflammatory Agents, Non-Steroidal ; Humans ; Ischemia ; Renal Circulation ; Renal Insufficiency ; Vasoconstriction

In order to investigate the effects of methoxyflurane on reneal functions, small dose of methoxyflurane was administered intravenously ot rabbits without anesthesia, or directly injected into the renal artery of the rabbits under urethane anesthesia and the following results were obtained. 1) 5ml/kg of 0.5% saturated solution of methoxyflurane administered intravenously over 10 minutes did not influence the excretion of urine, creatinine, elecrolyte or osmolarity. 2) 1ml/kg of the solution injected directly into the renal artery over 10 minutes markedly reduced urine volume. 3) Reduced urine volume was closely related to decreased renal blood flow by direct administeration of methoxyflurane into the renal artery. 4) From the above results, it is suggested that methoxyflurane has a direct effect on renal functions by hemodynamic change in the renal circulation.
Anesthesia ; Creatinine ; Hemodynamics ; Methoxyflurane* ; Osmolar Concentration ; Rabbits* ; Renal Artery ; Renal Circulation ; Urethane

PURPOSE: Recent development in ultrasonic Doppler instrumentation have allowed the direct noninvasive assessment of human renal artery blood flow. The authors conducted this study to assess noninvasive characterization of normal renal artery blood flow variables hopping to establish standards in normal children. METHODS: A total 97 normal Subjects(below the age 3 years) were examinated using by 2-D and doppler echocardiography. RESULTS: 1) Renal artery diameter increased with age and no difference was found between the Rt and Lt. 2) Renal blood flow increased with but the rate of increase was not constant in a 11 children, the older the children, the more variences were found in renal blood flow and no difference was noted between the Rt and Lt. 3) Pourcelot's index was not significantly different among 3 groups not between the Rt and Lt. 4) Renal artery diameter, renal arterial flow velocity integral, renal blood flow per minutes correlated with age, weight, height body surface area and weigh had the highest correlation among the physical variables. CONCLUSIONS: Authors are reporting normal renal blood flow variables in children and we hope it will be helpful for evaluationg renal hemodynamic changes.
Body Surface Area ; Child* ; Echocardiography, Doppler ; Hemodynamics ; Hope ; Humans ; Humulus ; Renal Artery ; Renal Circulation* ; Ultrasonics

PURPOSE: The goal of this study was to evaluate the effect of vascular compliance, resistance, and pulse rate on the resistive index (RI) by using an electrical circuit model to simulate renal blood flow. METHODS: In order to analyze the renal arterial Doppler waveform, we modeled the renal blood-flow circuit with an equivalent simple electrical circuit containing resistance, inductance, and capacitance. The relationships among the impedance, resistance, and compliance of the circuit were derived from well-known equations, including Kirchhoff's current law for alternating current circuits. Simulated velocity-time profiles for pulsatile flow were generated using Mathematica (Wolfram Research) and the influence of resistance, compliance, and pulse rate on waveforms and the RI was evaluated. RESULTS: Resistance and compliance were found to alter the waveforms independently. The impedance of the circuit increased with increasing proximal compliance, proximal resistance, and distal resistance. The impedance decreased with increasing distal compliance. The RI of the circuit decreased with increasing proximal compliance and resistance. The RI increased with increasing distal compliance and resistance. No positive correlation between impedance and the RI was found. Pulse rate was found to be an extrinsic factor that also influenced the RI. CONCLUSION: This simulation study using an electrical circuit model led to a better understanding of the renal arterial Doppler waveform and the RI, which may be useful for interpreting Doppler findings in various clinical settings.
Compliance ; Computer Simulation ; Electric Impedance ; Heart Rate ; Jurisprudence ; Pulsatile Flow ; Renal Artery ; Renal Circulation ; Ultrasonography, Doppler

PURPOSE: We have evaluated the influence of several variables such as vascular compliance and resistance and heart rate on the resistive index by the use of an electrical circuit model that simulates renal blood flow. MATERIALS AND METHODS: To analyze the renal artery Doppler waveform, we modeled the renal blood-flow circuit with an equivalent simple electrical circuit containing resistance, inductance and capacitance. The relationship between impedance and resistance and compliance of the circuit was derived from well-known equations including Kirchhoff's current law for an alternating current circuit. Simulated velocitytime profiles for pulsatile flow were generated by the use of Mathematica software (Wolfram Research, Champaign, IL USA) and the influence of resistance, compliance and pulse rate on waveforms and the resistive index were evaluated. RESULTS: Resistance and compliance altered the waveforms independently. The impedance of the circuit increased with increasing proximal compliance, proximal resistance and distal resistance. Impedance decreased with increasing distal compliance. The resistive index of the circuit decreased with increasing proximal compliance and resistance. The resistive index increased with increasing distal compliance and resistance. These results showed no tendency of a positive correlation between the impedance and resistive indices. The pulse rate is an extrinsic factor that also influences the resistive index. CONCLUSIONS: By the use of this simulation study using an electrical circuit model, a better understanding of the Doppler waveform and resistive index was achieved and the study findings may be useful in various clinical settings.
Compliance ; Electric Impedance ; Heart Rate ; Jurisprudence ; Pulsatile Flow ; Renal Artery ; Renal Circulation