Urinary pH as a determinant of prostaglandin E2 excretion by the conscious rat

1984 ◽  
Vol 66 (6) ◽  
pp. 675-681 ◽  
Author(s):  
J. Haylor ◽  
C. J. Lote ◽  
A. Thewles
Keyword(s):  
Prostaglandin E2 ◽  
Isotonic Saline ◽  
Tubular Secretion ◽  
Urine Flow ◽  
Urine Ph ◽  
Conscious Rat ◽  
Conscious Rats ◽  
Positive Linear Correlation ◽  
Solute Excretion ◽  
Oral Sodium

1. The urinary excretion of prostaglandin E2 (PGE2) was measured in conscious rats under conditions which produced either acid or alkaline urine, but similar change in fluid and solute excretion. 2. Oral isotonic saline increased both urine flow and sodium excretion but did not alter urinary PGE2 output (which remained constant at 80 pmol/3 h per rat) or urine pH (6.2). 3. When the urine was made alkaline (pH 7.8) by oral sodium bicarbonate or carbonate, urinary PGE2 was approximately 3-fold greater (P<0.00l) than the control (pH6.2). The urine flow and sodium output were also increased. 4. When the urine was made acidic (pH 5.7) by oral ammonium chloride, urinary PGE, excretion was reduced (P<0.01) to approximately half the control output. The urine flow and sodium output increased. 5. Within a group of 12 rats receiving oral isotonic saline a positive linear correlation coefficient (P<0.002) was established between urine pH and PGE2 excretion. 6. The results indicate that urine pH may be a determinant of PGE2 excretion in unrestrained, conscious rats. It seems likely that this effect of pH is mediated by a change in the passive reabsorption of PGE, in the distal nephron, although alternative explanations such as altered tubular secretion or synthesis cannot be categorically excluded.

Renal function in water snakes

1962 ◽  
Vol 203 (6) ◽  
pp. 995-1000 ◽  
Author(s):  
S. J. LeBrie ◽  
I. D. W. Sutherland
Keyword(s):  
Tubular Secretion ◽  
Urine Flow ◽  
Urinary Concentration ◽  
Clearance Ratio ◽  
Creatinine Concentration ◽  
Plasma Creatinine Concentration ◽  
Tenfold Increase ◽  
Solute Excretion ◽  
Water Snakes ◽  
Filtered Load

Electrolyte and osmolar concentrations of ureteral urine were compared with serum in several species of water snakes. Hyperosmotic urine was never observed, even after 48 hr of water deprivation. This finding is consistent with the countercurrent theory which precludes urinary concentration when Henle's loops are absent, as in reptilian kidneys. The creatinine/inulin clearance ratio may exceed 2.0, suggesting tubular secretion of creatinine. Tubular secretion is further suggested by the fact that the clearance ratio approaches unity when plasma creatinine concentration is elevated. Variations in glomerular activity are reflected in urine flow in snakes as shown by a direct relationship between clearance of inulin (GFR) and urine flow In snakes solute excretion is dependent on an increase in functional tubular population, with a concomitant increase in filtered load and not a decrease in tubular solute reabsorption. Evidence for this concept is presented and indicates that, over a tenfold increase in GFR, snakes continue to excrete about the same per cent of their filtered load. Water reabsorption, on the other hand, appears to be similar in character to that seen in higher vertebrates. Proximally, it appears to be dependent on solute reabsorption ("obligatory"), whereas distally it is influenced by ADH ("facultative").

Comparison of Oral Sodium Bicarbonate and Solifenacin Treatment in Female Overactive Bladder Patients With Acidic Urine pH

2021 ◽  
Vol 76 (1) ◽  
pp. 24-25
Author(s):  
Mehmet Giray Sönmez ◽  
Gökhan Ecer ◽  
Ahmet Atıcı ◽  
Mehmet Serkan Özkent ◽  
Mehmet Sinan İyisoy ◽  
...  
Keyword(s):  
Overactive Bladder ◽  
Sodium Bicarbonate ◽  
Urine Ph ◽  
Oral Sodium ◽  
Acidic Urine

scholarly journals Towards Further Verification of Physiologically-Based Kidney Models: Predictability of the Effects of Urine-Flow and Urine-pH on Renal Clearance

2018 ◽  
Vol 368 (2) ◽  
pp. 157-168 ◽  
Author(s):  
Takanobu Matsuzaki ◽  
Daniel Scotcher ◽  
Adam S. Darwich ◽  
Aleksandra Galetin ◽  
Amin Rostami-Hodjegan
Keyword(s):  
Renal Clearance ◽  
Urine Flow ◽  
Urine Ph ◽  
Physiologically Based

Urinary prostaglandin F2α excretion is not pH-dependent in the conscious rat: implications for the urinary prostaglandin E2/prostaglandin F2α ratio

1990 ◽  
Vol 78 (2) ◽  
pp. 181-184 ◽  
Author(s):  
J. Haylor ◽  
C. J. Lote
Keyword(s):  
Excretion Rate ◽  
Ph Dependence ◽  
Prostaglandin F2α ◽  
Urine Ph ◽  
Marked Contrast ◽  
Conscious Rat ◽  
Alkaline Urine ◽  
Site Of Action ◽  
Accurate Reflection

1. The influence of urine pH on the urinary excretion of prostaglandin (PG) F2α and the PGE2/PGF2α ratio has been examined in the conscious rat. 2. The basal urinary PGF2α excretion rate of 3.9 pmol/h (n = 23) did not vary with urine pH. In marked contrast, PGE2 excretion increased as the urine became more alkaline. The PGE2/PGF2α ratio therefore progressively increased from 1.5 to 22 as the pH of the urine changed from pH 5.8 to pH 7.8. 3. The independence of PGF2α excretion from urine pH: (a) excludes cyclo-oxygenase as a potential site of action for the pH-dependence of urinary PGE2 excretion; (b) suggests that the urinary PGE2/PGF2α ratio measured in alkaline urine may be a more accurate reflection of the kidneys, ability to synthesize these two prostaglandins in vivo; (c) suggests that control of urine pH is required before the urinary PGE2/PGF2α ratio can be employed as an index of PGE2 9-ketoreductase (EC 1.1.1.189) activity in vivo.

On the interaction of calcium, sodium, and water transport in the diuresing kidney

1968 ◽  
Vol 46 (2) ◽  
pp. 275-280 ◽  
Author(s):  
O. Schück ◽  
J. H. Cort
Keyword(s):  
Renal Function ◽  
Linear Relation ◽  
Filtration Rate ◽  
Urine Flow ◽  
Water Reabsorption ◽  
Osmotic Diuresis ◽  
Anesthetized Dogs ◽  
Permeability For Water ◽  
Solute Excretion ◽  
Tubular Permeability

Diuresis was induced in cats by infusion of 3% glucose in 10% ethanol. When urine flow had stabilized at high levels a solution of the Ca salt of ethylenediaminetetraacetate (Na2CaEDTA) was infused as a control for the effect of the EDTA molecule on renal function. The infusion was then changed over to the same molar rate of Na2EDTA, which resulted in a 30% decrease in serum Ca levels. Ca was then repleted rapidly as CaCl2 given intravenously, and the infusion was shifted back to Na2CaEDTA. The decrease in extracellular Ca concentration was associated with a significant antidiuresis. In further experiments on anesthetized dogs, osmotic diuresis was induced either by (a) infusion of hyperosmotic mannitol solutions, which were then shifted over to hypertonic NaCl, or (b) the same solutions in reverse order. Ca excretion correlated in linear fashion with Na excretion, but not with total solute excretion or with filtration rate. When Ca was added to the mannitol infusion, Na excretion increased in linear relation to Ca. It is suggested that Ca (a) decreases tubular permeability for water reabsorption and (b) decreases Na reabsorption, while Na (c) decreases Ca reabsorption. Mechanisms a and b would appear to involve membrane transport directly in the proximal tubule.

Interrelations of arsenate and phosphate transport in the dog kidney

1963 ◽  
Vol 205 (4) ◽  
pp. 707-714 ◽  
Author(s):  
J. M. Ginsburg ◽  
W. D. Lotspeich
Keyword(s):  
Phosphate Transport ◽  
Tubular Secretion ◽  
Tubular Reabsorption ◽  
Urine Flow ◽  
Phosphate Concentration ◽  
Plasma Phosphate ◽  
Osmotic Diuresis ◽  
Competitive Mechanism ◽  
Dog Kidney

The relation between arsenate and phosphate transport in the dog kidney was studied by measuring the renal clearance of arsenate labeled with its radioactive isotope As74. The experiments were performed during osmotic diuresis induced by mannitol. The results demonstrate certain similarities in the transport of these ions. Arsenate undergoes a net tubular reabsorption which is inhibited as the plasma phosphate concentration is raised. The inverse relationship between arsenate transport and the plasma As:P ratio suggests a competitive mechanism for the interaction between the two ions Like phosphate, arsenate transport is inhibited by glucose and this effect is reversed by phlorizin. An important difference between arsenate and phosphate transport is the sensitivity of arsenate transport to urine flow. In vivo reduction of arsenate to arsenite and a net tubular secretion of arsenite has been observed. The results are discussed in terms of the known ability of arsenate to substitute for phosphate in biochemical reactions.

BICARBONATE EXCRETION DURING HYPOTHERMIA

1963 ◽  
Vol 41 (1) ◽  
pp. 91-96 ◽  
Author(s):  
G. S. Kanter ◽  
R. H. Lubinski ◽  
I. M. Mielens
Keyword(s):  
Rectal Temperature ◽  
Plasma Levels ◽  
Excretion Rate ◽  
Artificial Respiration ◽  
Urine Flow ◽  
Urine Ph ◽  
Urinary Ph ◽  
Arterial Ph

The investigation was designed to determine whether the renal loss of bicarbonate contributes significantly to the acidosis of hypothermia. The excretion of bicarbonate during hypothermia was studied in five infused (6% creatinine in saline at 0.4 ml/minute) and five non-infused dogs. All animals were anesthetized and artificial respiration was not used. The rectal temperature was gradually reduced to the 26–27 °C range by approximately 4 hours of exposure to ice packing. After control, clearance periods of 30 minutes' duration were conducted serially and continually through the experiment. There was no significant increase in bicarbonate excretion during hypothermia in the non-infused group. The urinary pH remained at control levels of about 6.2. The fall in arterial pH was not due to urinary bicarbonate loss. The urinary pH in the infused group, which had a higher urine flow, increased to pH 6.7 due to increased excretion of bicarbonate. The urine pH in three animals with highest urine flows in this latter group approached plasma levels. The excretion rate of bicarbonate in the infused group, however, was similarly insufficient to account for the decrease in arterial pH. The hypothermic kidney is quite effective in reabsorbing bicarbonate.

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