Urine Flow (urine + flow)

Distribution by Scientific Domains

Terms modified by Urine Flow

  • urine flow rate

  • Selected Abstracts

    Uridine adenosine tetraphosphate affects contractility of mouse aorta and decreases blood pressure in conscious rats and mice

    ACTA PHYSIOLOGICA, Issue 2 2010
    P. B. Hansen
    Abstract Aim:, In the anaesthetized rat, uridine adenosine tetraphosphate (Up4A) is a circulating, endothelium-derived vasoconstrictor presumably operating as such in un-anaesthetized animals. The present study investigated the in vivo effects of Up4A in conscious mice and rats, and its direct vascular effects in the mouse aorta in vitro. Methods:,In vivo, Up4A was given as step-up infusion at rates of 8,512 nmol min,1 kg,1 for 30 min periods in chronically catheterized rodents. In vitro, the effect of Up4A on rings of mouse aortae mounted in a myograph was tested. Results:, High doses of Up4A (mice: 512 nmol min,1 kg,1; rats: 128 nmol min,1 kg,1) caused hypotension (99 4 to 64 7 mmHg and 114 3 to 108 3 mmHg, respectively, both P < 0.01). In rats, Up4A significantly decreased sodium excretion by >75% and potassium excretion by ,60% without significant changes in urine flow. Exposure of phenylephrine-contracted rings to increasing concentrations of Up4A elicited contraction at 10,7 and 10,6 mol L,1 (18 2% and 76 16% respectively); unexpectedly, 10,5 mol L,1 caused a biphasic response with a contraction (19 6%) followed by a relaxation (,46 6%). No relaxation was observed when the concentration was increased further. Bolus exposure to 10,5 mol L,1 of Up4A caused contraction (+80 2%). Added successively to untreated vessels, increasing concentrations of Up4A (10,7,10,5 mol L,1) induced a biphasic response of contraction followed by relaxation. Conclusion:, Up4A has direct biphasic effects on vascular smooth muscle of the mouse aorta but vasoconstriction dominates at low concentrations. In conscious rodents, step-up infusions of Up4A elicit hypotension and electrolyte retention. [source]

    Role of nitric oxide in the reflex diuresis in rabbits during pulmonary lymphatic obstruction

    K. M. McCormick
    The role of nitric oxide in the reflex diuresis in response to pulmonary lymphatic drainage was examined in anaesthetized, artificially ventilated New Zealand White rabbits. Pulmonary lymphatic drainage was obstructed by raising the pressure in a pouch created from the right external jugular vein. Pulmonary lymphatic obstruction resulted in a significant increase in urine flow from an initial control value of 8.9 0.5 ml (10 min),1 to 12.1 0.6 ml (10 min),1 during lymphatic obstruction (mean s.e.m.; n= 17, P < 0.001). This increase in urine flow was accompanied by a significant increase in the excretion of sodium. Additionally, renal blood flow remained unchanged during the increase in urine flow caused by lymphatic obstruction. Intravenous infusion of l -NAME, a non-selective inhibitor of nitric oxide synthase (NOS), abolished the reflex diuresis. Furthermore, intraperitoneal administration of the relatively selective neuronal NOS blocker, 7-nitroindazole also abolished the response. It was observed that infusion of a more soluble neuronal NOS blocker, 7-nitroindazole sodium salt (7-NINA), into the renal medulla also abolished the reflex diuresis. These findings suggest that the increase in urine flow in rabbits caused by pulmonary lymphatic obstruction is dependent upon the integrity of neuronal NOS activity within the renal medulla. [source]

    Renal Response to Arginine Vasopressin During the Oestrous Cycle in the Rat: Comparison of Glucose and Saline Infusion Using Physiological Doses of Vasopressin

    David E. Hartley
    The renal response to arginine vasopressin in the rat has been shown to depend on reproductive status. However there is no consensus as to when the kidney is most responsive. The varying results could depend on the protocol and the dose of hormone used. A study has been performed, with physiological doses of vasopressin, comparing the responses during infusion of hypotonic saline and glucose. After an equilibration period of 150 min, conscious rats were infused on each of the four days of the oestrous cycle with either isotonic saline (0.077 M) or 0.14 M glucose for a control period of 45 min. Vasopressin was then infused at 10-40 fmol min,1 for 1 h, followed by a recovery period of 90 min. Timed urine samples were collected for determination of volume, sodium concentration and osmolality. During the control period urine flow was greatest at oestrus and dioestrus day 2 and sodium excretion on dioestrus day 2 irrespective of the infusate. Vasopressin concentrations achieved lay within the physiological range and no difference was observed between the different days for a given dose. Infusion of vasopressin in both saline and glucose produced a dose-dependent antidiuresis, the greatest responses being seen of pro-oestrus and dioestrus day 2. It was only with the highest rate of infusion that a significant increase in sodium excretion was seen on each day of the cycle and the greatest responses were seen on pro-oestrus and dioestrus day 1 for both infusates. Thus the kidney shows the greatest response to physiological doses of vasopressin at pro-oestrus and dioestrus day 1 irrespective of the infusate employed. [source]

    Norepinephrine causes a pressure-dependent plasma volume decrease in clinical vasodilatory shock

    Background: Recent experimental studies have shown that a norepinephrine-induced increase in blood pressure induces a loss of plasma volume, particularly under increased microvascular permeability. We studied the effects of norepinephrine-induced variations in the mean arterial pressure (MAP) on plasma volume changes and systemic haemodynamics in patients with vasodilatory shock. Methods: Twenty-one mechanically ventilated patients who required norepinephrine to maintain MAP ,70 mmHg because of septic/postcardiotomy vasodilatory shock were included. The norepinephrine dose was randomly titrated to target MAPs of 60, 75 and 90 mmHg. At each target MAP, data on systemic haemodynamics, haematocrit, arterial and mixed venous oxygen content and urine flow urine were measured. Changes in the plasma volume were calculated as 100 (Hctpre/Hctpost,1)/ (1,Hctpre), where Hctpre and Hctpost are haematocrits before and after intervention. Results: Norepinephrine doses to obtain target MAPs of 60, 75 and 90 mmHg were 0.200.18, 0.290.18 and 0.420.31 ,g/kg/min, respectively. From 60 to 90 mmHg, increases in the cardiac index (15%), systemic oxygen delivery index (25%), central venous pressure (CVP) (20%) and pulmonary artery occlusion pressure (33%) were seen, while the intrapulmonary shunt fraction was unaffected by norepinehrine. Plasma volume decreased by 6.5% and 9.4% (P<0.0001) when blood pressure was increased from 60 to 75 and 90 mmHg, respectively. MAP (P<0.02) independently predicted the decrease in plasma volume with norepinephrine but not CVP (P=0.19), cardiac index (P=0.73), norepinephrine dose (P=0.58) or urine flow (P=0.64). Conclusions: Norepinephrine causes a pressure-dependent decrease in the plasma volume in patients with vasodilatory shock most likely caused by transcapillary fluid extravasation. [source]

    Effect of administration mode (patient vs physician) and patient's educational level on the Turkish version of the International Prostate Symptom Score

    Murat Bozlu
    Abstract Objectives: To compare the effectiveness of the International Prostate Symptom Score (IPSS) when administered by the physician to when self-administered by the patient. The effect of the patient's educational level on the IPSS was also evaluated. Methods: One hundred and seven previously untreated patients with symptomatic benign prostatic hyperplasia (BPH) completed the Turkish version of the International Prostate Symptom Score (Turkish I-PSS) and quality of life (QOL) questionnaires during a single office visit, first on their own and then with an interviewing physician. The patients were categorized into three groups according to their educational levels. Paired t -tests were performed to compare the total IPSS (tIPSS) and QOL results between the two testing modes. IPSS and QOL scores resulting from both modes were compared using a kappa test. Differences between the physician-assisted and self-administered scores among the different educational groups were further compared using a one-way anova test and Post Hoc Multiple Comparisons. To compare the objective effectiveness of tIPSS and QOL between the two testing modes, we selected the positive actual state, which was maximum urine flow (Qmax) of 15 mL/s or less and constructed receiver operating characteristics (ROC) curves for all patients. This estimation was constructed for each educational level. Results: There were no statistical differences in IPSS and QOL values obtained by the patients or physicians (P > 0.05). The ROC areas for tIPSS were 0.94 and 0.93, and the ROC areas for QOL scores were 0.97 and 0.91 for information obtained by physicians and patients, respectively. When IPSS answers and QOL scores were evaluated separately, consistency was found across both modes of administration. However, there were lower levels of consistency in answers to IPSS questions 2, 5 and 6 (P = 0.59;0.42; 0.52, respectively). There was no significant difference among the aforementioned data in the educational groups. Conclusion: Although the total IPSS and QOL scores were not affected by the different modes of administration, we recommend that the physicians should evaluate answers to questions 2, 5 and 6 carefully. The present study demonstrates that the educational level did not affect the IPSS and QOL when administered either by the physician or the patient. [source]

    Sling operations in the treatment of stress urinary incontinence: How to adjust sling tension

    Ibraheem Mahmoud Ezzat
    Abstract Aim:, To find an objective method of adjusting sling tension in order to avoid postoperative urinary obstruction. Methods:, Thirty-five female patients with type II/III and type III stress urinary incontinence were treated using a sling procedure. Pubovaginal fascial slings were implanted in 20 patients and polytetrafluoroethylene patch slings with nylon sutures were implanted in 15 patients. During the procedures the urinary bladder was partially full and the patients, who were under spinal or epidural anesthesia, were asked to cough and strain. The proper tension that effectively prevents urine leakage was selected and the corresponding suture length was marked. An objective new method to adjust sling tension was used. As part of this method, the abdominal bulge index is added to the suture length before tying. Results:, Short-term follow-up of 6,12 months showed that 33 of 35 patients reported no leakage of urine (94%). Two patients had unsatisfactory urge incontinence. We did not encounter postoperative urinary retention in any patient. No significant post-voiding residual urine was reported. None of our patients in this series have complained of difficulties during micturition or the need to strain during voiding. Conclusion:, Proper adjustment of sling tension using the abdominal bulge index has eliminated postoperative urinary retention and obstructed urine flow, including any appreciable amount of post-voiding residual urine. This method has been found to be both objective and reproducible. [source]

    Uterus masculinus: an unusual complication in a case of feline urethral obstruction

    Gabriella Sfiligoi DVM
    Abstract A 6-year-old, male castrated domestic short hair cat presented for urethral obstruction. Despite passage of a urinary catheter, urine could not be drained through the catheter, but urine flow was noted around the catheter. Special imaging studies, including ultrasound and fluoroscopy, revealed that the catheter had been passed into an abnormal small bicornuate structure that entered the urethra from dorsally within the pelvic canal. This structure was believed to be a uterus masculinus or remnants of the Mullerian ducts. The anomalous structure was not felt to be related to the cause of the urethral obstruction, but was simply an incidental finding which resulted in difficult catheterization. [source]

    Changes in renal hemodynamics and urodynamics in rats with chronic hyperoxaluria and after acute oxalate infusion: Role of free radicals

    Ho-Shiang Huang
    Abstract Aims The aim of this study was to evaluate possible changes in renal hemodynamic and urodynamic parameters in rats with chronic hyperoxaluria and after acute oxalate challenge. We also evaluated the possible association between free radical (FR) production, hyperoxaluria, and calcium oxalate (CaOx) calculi formation. Methods Chronic hyperoxaluria was induced by adding 0.75% ethylene glycol (EG) to the drinking water of male Wistar rats. After 7, 21, and 42 days of treatment, urinary biochemistry, oxalate levels, and lipid peroxides were measured. Kidney calculi were examined by polarizing microscopy. In the second part of the experiments, 1, 10, 20, and 30 mg kg,1 hr,1 oxalate was infused, by means of an intrarenal arterial catheter (IRA), into normal rats sequentially. Superoxide dismutase (SOD) infusion by means of IRA, in addition to oxalate, was also performed to check its influence on the altered renal function after oxalate infusion. In both the acute and chronic groups, renal blood flow (RBF), cortical microvascular blood flow (CMVBF), glomerular filtration rate (GFR), urine flow (UV), and urinary sodium excretion (UNaV) were measured, and chemiluminescence (CL) was examined in the renal venous blood. Results Levels of urinary lipid peroxides and enzymuria had increased since day 7, and increased the size of numbers of CaOx crystals in the kidney were noted beginning on day 21, but elevated CL was detectable only on day 7 after 0.75% EG treatment. Decreased UV and UNaV were noted in the 42-day EG group, although the 24-hr creatinine clearance values were normal in all experimental groups. On the other hand, RBF, GFR, and CMVBF were attenuated with elevated FR when the oxalate concentration was higher than 10 mg kg,1 hr,1 in the acute oxalate infusion group. With SOD pretreatment, the decreased RBF, GFR, and CMVBF could be reversed at 10 mg kg,1 hr,1 of oxalate, and be partially reversed at 20. FR also could be reduced significantly at 10 and 20 mg kg,1 hr,1 of oxalate. Conclusions Decreased urine flow and sodium excretion were the main renal functions affected by chronic hyperoxaluria. However, that only the 42-day EG group had a decreased tubular function cannot be fully explained by the persistent tubular enzymuria and increased lipid peroxides that began on day 7 after EG treatment. With acute oxalate infusion, the major insult to renal function was renal hemodynamics. Pretreated SOD could reverse the attenuated hemodynamics and reduce the elevated FR partly, which suggested that FR is responsible for oxalate toxicity. Neurourol. Urodynam. 22:176,182, 2003. 2003 Wiley-Liss, Inc. [source]

    Urine flowing: A phenomenological study of living with a urinary catheter,

    Mary H. Wilde
    Abstract The experience of living with a long-term urinary catheter was investigated with a community-dwelling sample of 14 adults ranging in age from 35 to 95 who had worn a catheter for 6 months to 18 years. Data were obtained by audiotaped face-to-face interviews. Merleau-Ponty's phenomenology and van Manen's methodology guided the study. Living with a urinary catheter was found to be like living with the forces of flowing water. People were keenly aware of the flow of urine through their catheters, and they noticed when their bags needed emptying or when urine drainage seemed sluggish or obstructed. The metaphor of urine flowing like water may provide a teaching heuristic for assisting clients in adjusting to living with a catheter. Implications for further research focus on understanding the relationship between sensitivity to the dynamics of urine flow and urinary tract infection. 2002 John Wiley & Sons, Res Nurs Health 25:14,24, 2002. [source]

    The abuse of diuretics as performance-enhancing drugs and masking agents in sport doping: pharmacology, toxicology and analysis

    Amy B Cadwallader
    Diuretics are drugs that increase the rate of urine flow and sodium excretion to adjust the volume and composition of body fluids. There are several major categories of this drug class and the compounds vary greatly in structure, physicochemical properties, effects on urinary composition and renal haemodynamics, and site and mechanism of action. Diuretics are often abused by athletes to excrete water for rapid weight loss and to mask the presence of other banned substances. Because of their abuse by athletes, diuretics have been included on The World Anti-Doping Agency's (WADA) list of prohibited substances; the use of diuretics is banned both in competition and out of competition and diuretics are routinely screened for by anti-doping laboratories. This review provides an overview of the pharmacology and toxicology of diuretics and discusses their application in sports. The most common analytical strategies currently followed by the anti-doping laboratories accredited by the WADA are discussed along with the challenges laboratories face for the analysis of this diverse class of drugs. [source]

    Dual modulation of urinary bladder activity and urine flow by prostanoid EP3 receptors in the conscious rat

    MJ Jugus
    Background and purpose:, Cyclooxygenase inhibitors function to reduce levels of prostaglandin E2 (PGE2) and are broadly efficacious in models of bladder overactivity. We therefore investigated a regulation of urinary bladder function in conscious rats by modulation of the EP3 receptor for PGE2. Experimental approach:, The activity of the EP3 receptor agonist GR63799X, and EP3 receptor antagonists, CM9 and DG041, at recombinant EP3 receptors was evaluated in vitro. In vivo, intraduodenal dosing during conscious, continuous-filling cystometry of spontaneously hypertensive rats was utilized to determine the urodynamic effect of EP3 receptor modulation. Key results:, GR63799X dose-dependently (0.001,1 mgkg,1) reduced bladder capacity, as indicated by a reduction in both the micturition interval and volume of urine per void. In contrast, CM9 (10 and 30 mgkg,1) and DG041 (30 mgkg,1) enhanced bladder capacity, as indicated by significantly longer micturition intervals and larger void volumes. CM9 and DG041 inhibited the responses to GR63799X supporting the in vivo activity of these pharmacological agents at the EP3 receptor. In addition to its effect on bladder capacity, GR63799X increased endogenous urine production. Intra-arterial infusion of saline mimicked the enhancement of urine flow observed with GR63799X, and the response was inhibited by CM9. Conclusions and implications:, These data support the EP3 receptor as a modulator of urinary bladder activity in the conscious rat, and in addition, indicate a role for EP3 receptor activity in regulating urine flow. [source]

    Characterization of the Biomechanical Properties of T4 Pili Expressed by Streptococcus pneumoniae,A Comparison between Helix-like and Open Coil-like Pili

    CHEMPHYSCHEM, Issue 9-10 2009
    Mickal Castelain Dr.
    Abstract Adhesion strategies: Open coil-like T4 pili use different adhesion strategies in the presence of external forces (see figure) compared to the helix-like P pili. When exposed to significant forces, bacteria expressing helix-like pili remain attached by distributing the external force among a multitude of pili, whereas bacteria expressing open coil-like pili sustain large forces primarily by their multitude of binding adhesins. Bacterial adhesion organelles, known as fimbria or pili, are expressed by Gram-positive as well as Gram-negative bacteria families. These appendages play a key role in the first steps of the invasion and infection processes, and they therefore provide bacteria with pathogenic abilities. To improve the knowledge of pili-mediated bacterial adhesion to host cells and how these pili behave under the presence of an external force, we first characterize, using force measuring optical tweezers, open coil-like T4 pili expressed by Gram-positive Streptococcus pneumoniae with respect to their biomechanical properties. It is shown that their elongation behavior can be well described by the worm-like chain model and that they possess a large degree of flexibility. Their properties are then compared with those of helix-like pili expressed by Gram-negative uropathogenic Escherichia coli (UPEC), which have different pili architecture. The differences suggest that these two types of pili have distinctly dissimilar mechanisms to adhere and sustain external forces. Helix-like pili expressed by UPEC bacteria adhere to host cells by single adhesins located at the distal end of the pili while their helix-like structures act as shock absorbers to dampen the irregularly shear forces induced by urine flow and to increase the cooperativity of the pili ensemble, whereas open coil-like pili expressed by S. pneumoniae adhere to cells by a multitude of adhesins distributed along the pili. It is hypothesized that these two types of pili represent different strategies of adhering to host cells in the presence of external forces. When exposed to significant forces, bacteria expressing helix-like pili remain attached by distributing the external force among a multitude of pili, whereas bacteria expressing open coil-like pili sustain large forces primarily by their multitude of binding adhesins which presumably detach sequentially. [source]


    EI Boesen
    SUMMARY 1Pathological changes to the kidney, such as vascular remodelling, have been found in several models of hypertension and may contribute to the maintenance of hypertension or confer susceptibility to redeveloping hypertension after the original prohypertensive stimulus is withdrawn. 2To investigate whether noradrenaline-induced hypertension induces persistent, functionally important changes to the kidney, the acute pressure,natriuresis relationship was characterized in anaesthetized rats under controlled neural and hormonal conditions following chronic (14 days) intravenous infusion of noradrenaline (48 g/kg per h) or vehicle (0.04 mg/mL ascorbic acid and 0.156 mg/mL NaH2PO42H2O in 10 IU/mL heparinized saline). 3Conscious mean arterial pressure was significantly elevated by infusion of noradrenaline at 48 g/kg per h (+10 2 mmHg at Day 14; P < 0.01 vs vehicle group). The acute relationships between arterial pressure and renal blood flow, glomerular filtration rate, Na+ excretion and urine flow were not significantly different between the noradrenaline- and vehicle-infused rats immediately after termination of noradrenaline infusion. 4In summary, chronic intravenous noradrenaline infusion did not cause persistent changes in renal function, indicating that, in contrast with many models of hypertension, this model does not induce underlying prohypertensive changes to the kidney. [source]