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Journal of Applied Physiology Sep 1959
Topics: Carbon Dioxide; Cell Respiration; Diuresis; Heart; Heart Atria; Humans; Mechanoreceptors; Respiration
PubMed: 13840928
DOI: 10.1152/jappl.1959.14.5.844 -
Farmakologiia I Toksikologiia 1956
Topics: Diuresis; Diuretics; Humans; Procaine
PubMed: 13448025
DOI: No ID Found -
Lancet (London, England) Sep 1970
Clinical Trial
Topics: Diuresis; Female; Furosemide; Humans; Male; Smoking
PubMed: 4194976
DOI: 10.1016/s0140-6736(70)90152-2 -
The Journal of Pharmacology and... Apr 2011Strychnine-sensitive glycine receptors and glycine-immunoreactive fibers are expressed in the hypothalamic paraventricular nucleus (PVN), yet the functional significance... (Comparative Study)
Comparative Study
Strychnine-sensitive glycine receptors and glycine-immunoreactive fibers are expressed in the hypothalamic paraventricular nucleus (PVN), yet the functional significance of this innervation is unclear. Therefore, these studies examined the changes in cardiovascular and renal function and renal sympathetic nerve activity (RSNA) produced by the microinjection of glycine (5 and 50 nmol) into the PVN of conscious Sprague-Dawley rats. Microinjection of glycine into, but not outside of, the PVN dose-dependently increased urine flow rate and urinary sodium excretion and decreased RSNA. At the higher dose, PVN glycine also decreased heart rate; neither 5 nor 50 nmol PVN glycine altered mean arterial pressure. The glycine (50 nmol)-evoked diuresis and natriuresis were abolished in rats continuously infused intravenously with [Arg(8)]-vasopressin. Furthermore, chronic bilateral renal denervation prevented the bradycardia and diuresis to PVN glycine and blunted the natriuresis. In other studies, unilateral PVN pretreatment with the glycine receptor antagonist strychnine (1.6 nmol) prevented the effects of PVN glycine (50 nmol) on heart rate, RSNA, and renal excretory function. When microinjected bilaterally, PVN strychnine (1.6 nmol per site) evoked a significant increase in heart rate and RSNA without altering renal excretory function. These findings demonstrate that in conscious rats glycine acts in the PVN to enhance the renal excretion of water and sodium and decrease central sympathetic outflow to the heart and kidneys. Although endogenous PVN glycine inputs elicit a tonic control of heart rate and RSNA, the renal excretory responses to PVN glycine seem to be caused primarily by the inhibition of arginine vasopressin secretion.
Topics: Animals; Blood Pressure; Diuresis; Glycine; Heart Rate; Infusions, Intraventricular; Kidney; Male; Microinjections; Natriuresis; Paraventricular Hypothalamic Nucleus; Rats; Rats, Sprague-Dawley; Sympathetic Fibers, Postganglionic
PubMed: 21233196
DOI: 10.1124/jpet.110.175398 -
The American Journal of Physiology Aug 1997The renal-excretory responses to changes in renal perfusion pressure (RPP) were studied in anesthetized young (3 mo old), adult (12 mo old), and senescent (24 mo old)...
The renal-excretory responses to changes in renal perfusion pressure (RPP) were studied in anesthetized young (3 mo old), adult (12 mo old), and senescent (24 mo old) rats to evaluate whether the pressure diuresis and natriuresis mechanism is altered as a function of age. Experiments were performed in anesthetized animals in which nervous and systemic hormonal influences to the kidney were fixed. Mean arterial pressure was similar in all three groups: 97.6 +/- 2.6, 102.1 +/- 3.7, and 95.2 +/- 5.2 mmHg in young, adult, and senescent rats, respectively. The relationships between RPP and diuresis/natriuresis or fractional excretions of water and sodium were similar in young and adult rats. However, in senescent rats the pressure-diuretic and pressure-natriuretic responses were slightly shifted to the right, so that diuresis and natriuresis were significantly lower at higher levels of RPP. Glomerular filtration rate was well autoregulated, and there were no differences between young and adult rats at each level of RPP. However, a significantly lower glomerular filtration rate was observed in senescent rats. These results indicate an age-related decline in the pressure-dependent sodium and water excretion that appears to be due to a decrease in glomerular filtration and an increase in tubular sodium reabsorption.
Topics: Aging; Animals; Blood Pressure; Diuresis; Glomerular Filtration Rate; Male; Natriuresis; Rats; Rats, Wistar; Renal Circulation
PubMed: 9277541
DOI: 10.1152/ajpregu.1997.273.2.R578 -
Journal of the American Society of... Jul 1991Besides being a potent renal vasoconstrictor, endothelin causes diuresis and natriuresis. At which site along the nephron and how endothelin alters water and sodium...
Besides being a potent renal vasoconstrictor, endothelin causes diuresis and natriuresis. At which site along the nephron and how endothelin alters water and sodium handling in the tubule remain to be clarified. It was found that endothelin (75 pmol) given as an i.v. infusion in vivo to rats caused diuresis and urinary sodium excretion to double but did not affect glomerular filtration rate and renal plasma flow. On raising the dose of endothelin to 150 pmol, a further increase in diuresis and natriuresis was found, whereas glomerular filtration rate fell 33% and renal plasma flow fell 36%; 300 pmol of endothelin reduced glomerular filtration rate by 73% and renal plasma flow by 77% but did not significantly affect diuresis and absolute sodium excretion. It did, however, increase fractional sodium excretion eightfold. Lithium clearance studies of changes in tubular handling of water and sodium indicated that infusion of 150 pmol of endothelin to rats caused a reduction in absolute (pre, 84.7 +/- 5.9; post, 47.9 +/- 6.1 microEq/min/100 g) and fractional (pre, 85.7 +/- 3.0; post, 64.7 +/- 6.4%) proximal reabsorption of sodium. Endothelin infusion (150 pmol) was not associated with any significant change in plasma atrial natriuretic peptide levels, which on average remained comparable to those in rats given the vehicle alone (49.7 +/- 8.4 versus 46.3 +/- 5.6 pg/mL). In the isolated perfused rat kidney preparation, exposure to 150 pmol of endothelin significantly increased fractional sodium excretion over preinjection values (pre, 2.2 +/- 0.2; post, 7.3 +/- 1.0%) despite a marked decrease in glomerular filtration rate and renal perfusate flow. Additional in vivo experiments showed that oral administration of the specific 5-lipoxygenase inhibitor L-651,392 to rats prevented the increase in urine flow rate (pre, 5.7 +/- 0.1; post, 6.6 +/- 0.8 microL/min), and in absolute (pre, 0.33 +/- 0.04; post, 0.37 +/- 0.05 microEq/min) and fractional (pre, 0.10 +/- 0.02; post, 0.11 +/- 0.03%) sodium excretion caused by bolus i.v. infusion of endothelin (150 pmol). Similarly, a specific leukotriene C4/D4 receptor antagonist, L-649,923, also prevented the diuretic and natriuretic effect of 150 pmol of endothelin i.v. infusion. These findings show that (1) endothelin has a diuretic and natriuretic effect that is independent of its action on renal hemodynamics; (2) this effect depends on a direct action on the proximal tubules; (3) atrial natriuretic peptide does not appear to be involved in this effect; and (4) the diuretic and natriuretic responses to endothelin are mediated by 5-lipoxygenase products.
Topics: Animals; Arachidonate 5-Lipoxygenase; Arachidonic Acid; Atrial Natriuretic Factor; Diuresis; Endothelins; In Vitro Techniques; Kidney Tubules, Proximal; Male; Natriuresis; Perfusion; Phenylbutyrates; Rats; Rats, Inbred Strains; Receptors, Immunologic; Receptors, Leukotriene
PubMed: 1655094
DOI: 10.1681/ASN.V2157 -
Psychological Reports Jun 1973
Topics: Alcohol Drinking; Animals; Diuresis; Ethanol; Pyrazoles; Rats; Water-Electrolyte Balance
PubMed: 4709815
DOI: 10.2466/pr0.1973.32.3c.1209 -
Peptides Feb 2001Diuresis was studied in vivo by measuring the loss of tritiated water. The basal rate of water loss (5 nl/min) represents respiratory and cuticular losses, whereas...
Diuresis was studied in vivo by measuring the loss of tritiated water. The basal rate of water loss (5 nl/min) represents respiratory and cuticular losses, whereas higher rates reflect urine output, which reaches 20 nl/min after injection of 1 microl distilled water. This response to hypervolemia involves release of a diuretic hormone(s) into the hemolymph. However, housefly diuretic peptides increased urine output to a maximum of only 7 nl/min, and higher rates may require fluid reabsorption from the hindgut to be reduced. Diuresis is partially blocked by injected anti-muscakinin antibodies, providing evidence of a hormonal function for this insect myokinin.
Topics: Animals; Diuresis; Houseflies; Neuropeptides
PubMed: 11179808
DOI: 10.1016/s0196-9781(00)00372-7 -
Magnetic Resonance in Medicine Mar 2005Renal function is highly correlated with the sodium concentration gradient along the corticomedullary axis. The application of 3D high-resolution sodium magnetic...
Renal function is highly correlated with the sodium concentration gradient along the corticomedullary axis. The application of 3D high-resolution sodium magnetic resonance imaging (MRI) provided a means to quantify in vivo the spatial and temporal changes in renal tissue sodium concentration under normal and diuretic conditions. A detailed, pixel-by-pixel analysis of the intact rat kidney sodium MR images yielded a quantitative measure of the corticomedullary sodium gradient before and at early and later times after the administration of two distinct diuretic agents, furosemide and mannitol. Furosemide, a loop diuretic, induced a fivefold reduction in the cortical-outer medullary sodium gradient, whereas mannitol, an osmotic diuretic, did not affect this gradient. Both diuretics induced a 50% decrease in the sodium concentration of the inner medulla; however, mannitol exerted its effect twice as fast as furosemide with a 2.5-min exponential decay constant. These specific changes were attributed to the different mechanism of action and site of activity of each diuretic agent. Thus, high-resolution (23)Na MRI offers a unique, noninvasive tool for functional imaging of the kidney physiology.
Topics: Analysis of Variance; Animals; Diuresis; Diuretics; Female; Furosemide; Image Processing, Computer-Assisted; Kidney; Magnetic Resonance Imaging; Mannitol; Rats; Rats, Inbred Lew; Sodium
PubMed: 15723399
DOI: 10.1002/mrm.20359 -
Clinical Science May 1954
Topics: Celiac Disease; Diuresis; Steatorrhea
PubMed: 13161187
DOI: No ID Found