Micropuncture Study of Inorganic Phosphate Excretion in the Rat *

Exposure to hyperoxia (500–600 torr) or low pH (4.5) for 72 h or NaHCO3 infusion for 48 h were used to create chronic respiratory (RA) or metabolic acidosis (MA) or metabolic alkalosis in freshwater rainbow trout. During alkalosis, urine pH increased, and [titratable acidity (TA) −[Formula: see text]] and net H+ excretion became negative (net base excretion) with unchanged [Formula: see text] efflux. During RA, urine pH did not change, but net H+ excretion increased as a result of a modest rise in [Formula: see text] and substantial elevation in [TA −[Formula: see text]] efflux accompanied by a large increase in inorganic phosphate excretion. However, during MA, urine pH fell, and net H+excretion was 3.3-fold greater than during RA, reflecting a similar increase in [TA −[Formula: see text]] and a smaller elevation in phosphate but a sevenfold greater increase in[Formula: see text] efflux. In urine samples of the same pH, [TA − [Formula: see text]] was greater during RA (reflecting phosphate secretion), and[Formula: see text] was greater during MA (reflecting renal ammoniagenesis). Renal activities of potential ammoniagenic enzymes (phosphate-dependent glutaminase, glutamate dehydrogenase, α-ketoglutarate dehydrogenase, alanine aminotransferase, phospho enolpyruvate carboxykinase) and plasma levels of cortisol, phosphate, ammonia, and most amino acids (including glutamine and alanine) increased during MA but not during RA, when only alanine aminotransferase increased. The differential responses to RA vs. MA parallel those in mammals; in fish they may be keyed to activation of phosphate secretion by RA and cortisol mobilization by MA.

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The secretion of inorganic phosphate by the kidney.—II. Influence of the pituitary gland and of the wall of the third ventricle

Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character ◽

10.1098/rspb.1925.0069 ◽

1925 ◽

Vol 99 (694) ◽

pp. 70-91 ◽

Cited By ~ 9

Keyword(s):

Pituitary Gland ◽

Inorganic Phosphate ◽

Third Ventricle ◽

Inorganic Phosphorus ◽

Inorganic Salts ◽

Potassium Ions ◽

Separate Study ◽

The Third ◽

Phosphate Excretion

In previous experiments on the diuretic properties of calcium and potassium ions (1), we tried the effect of removing various organs from the whole animal, in order to investigate whether they exert some influence on the secretory functions of the kidney. We were struck by the fact that after removal of the pituitary body, the kidney may lose in the following few hours its power of secreting inorganic phosphorus. Since in those experiments inorganic salts, which may have an influence on P secretion, were injected, we started a separate study of the action of the pituitary on phosphate excretion.

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Parathyroid hormone-induced phosphate excretion following preequilibration with 32P

AJP Renal Physiology ◽

10.1152/ajprenal.1984.246.4.f373 ◽

1984 ◽

Vol 246 (4) ◽

pp. F373-F378 ◽

Cited By ~ 1

Author(s):

R. F. Wideman

Keyword(s):

Parathyroid Hormone ◽

Inorganic Phosphate ◽

Fractional Excretion ◽

Secretory Component ◽

Experimental Animals ◽

Phosphate Excretion ◽

Pi Transport

Parathyroid hormone (PTH) stimulates a secretory component of avian renal inorganic phosphate (Pi) transport, but the secreted Pi does not appear to be derived directly from peritubular (plasma) Pi. In the present study, experiments were conducted to determine whether differences in parathyroid status during 32P infusion influenced entry of the isotope into the Pi secretory pool. Fractional excretion values for Pi (FEPi) and 32P (FE32P) were compared in normal and parathyroidectomized (PTX) anesthetized birds that had been preinfused with 32P for 0, 90, and 240 min before PTH infusion. The results demonstrate that in the absence of exogenous PTH, FEPi is identical to FE32P in normal and PTX birds, reflecting full equilibration of 32P with excreted Pi under these conditions; and, regardless of the duration of 32P preequilibration or the parathyroid status of the experimental animals, exogenous PTH always causes FEPi to exceed FE32P. It is concluded that the Pi secretory pool is inaccessible to 32P under conditions that should markedly alter cellular Pi influx and efflux.

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THE EFFECT OF PARATHYROID HORMONE ON PHOSPHATE EXCRETION IN THE RAT

Journal of Endocrinology ◽

10.1677/joe.0.0090292 ◽

1953 ◽

Vol 9 (3) ◽

pp. 292-300 ◽

Cited By ~ 15

Author(s):

BERYL M. A. DAVIES ◽

A. H. GORDON

Keyword(s):

Parathyroid Hormone ◽

Inorganic Phosphate ◽

Phosphate Level ◽

Aluminium Sulphate ◽

Phosphate Excretion ◽

Serum Inorganic Phosphate ◽

Serum And Urine

The magnitude of the decrease in serum inorganic phosphate and the increase in urine phosphate of parathyroidectomized rats caused by injected parathyroid hormone has been studied. About 3 u.s.p. units of this hormone have been found to cause maximum changes in both serum and urine phosphate. Both responses depend on the respective initial phosphate level. Urine phosphate levels too high for more than minimal changes in phosphate excretion have been reduced by diets containing aluminium sulphate.

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Changes in inorganic phosphate excretion induced by renal arterial infusion of calcium

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1963.205.5.1025 ◽

1963 ◽

Vol 205 (5) ◽

pp. 1025-1032 ◽

Cited By ~ 57

Author(s):

A. R. Lavender ◽

Theodore N. Pullman

Keyword(s):

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Filtration Rate ◽

Renal Plasma Flow ◽

Tubular Reabsorption ◽

Water Excretion ◽

Phosphate Excretion ◽

Constant Rate ◽

Calcium Infusion ◽

Inorganic Phosphate Excretion

Calcium chloride in varying concentrations was infused at a slow and constant rate into the renal artery of one kidney in the dog. The opposite kidney served as a control. In 20 experiments, the mean glomerular filtration rate and effective renal plasma flow diminished in the infused relative to the noninfused kidneys. Mean phosphate excretion was decreased in the infused relative to the control kidneys by both a fall in filtered phosphate and a rise in the net tubular reabsorption of phosphate. Mean calcium, sodium, and water excretion did not change in the infused relative to the control kidneys during calcium infusion. The data indicate that hypercalcemia acts directly on the kidney to decrease phosphate excretion by decreasing glomerular filtration rate and increasing net tubular reabsorption of phosphate.

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URINARY TRACT STONE DISEASE

The Professional Medical Journal ◽

10.29309/tpmj/2011.18.02.2060 ◽

2011 ◽

Vol 18 (02) ◽

pp. 243-245

Author(s):

MUHAMMAD ISHAQ ◽

ISRAR AHMED AKHUND ◽

MAULA BUX LAGHARI ◽

Muhammad Sabir

Keyword(s):

Inorganic Phosphate ◽

Renal Stone ◽

Stone Formation ◽

Mean Value ◽

Stone Disease ◽

Stone Formers ◽

The World ◽

Urinary Tract Stone ◽

Inorganic Phosphate Excretion ◽

The Mean

Aims & Objectives: Geographical variation in the rates of kidney stones has been observed for many years. Pakistan is situated in stone belt. Calculus diseases is endemic in Pakistan, perhaps the incidence in Pakistan is highest in the world. Purpose: To evaluate etiology and biochemical risk factors (inorganic phosphate) in the Peshawar. Subjects & Methods: Study was conducted at LHR and Hayatabad Hospitals of Peshawar for the period of nine months. Two hundred patients and same number of controls were selected. Results: The mean value of mean inorganic phosphate in non stone formers were less than that of stone formers. The mean of urinary inorganic phosphate excretion in stone formers was greater than that of non-stone formers. Conclusions: We conclude that inorganic phosphate is an independent risk factor for renal stone formation.

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Renal responses to parathyroid hormone in young chickens

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1994.267.1.r295 ◽

1994 ◽

Vol 267 (1) ◽

pp. R295-R302

Author(s):

J. Q. Feng ◽

N. B. Clark

Keyword(s):

Parathyroid Hormone ◽

Inorganic Phosphate ◽

Age Groups ◽

Perinatal Period ◽

Receptor Interaction ◽

Calcium Loading ◽

Late Embryogenesis ◽

Intermediate Response ◽

Inorganic Phosphate Excretion ◽

Renal Responses

Renal clearance studies were performed in chicks 1, 5, and 9 days after hatching. Calcium gluconate was infused to block endogenous parathyroid hormone (PTH) secretion, whereas ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) was infused to stimulate endogenous PTH secretion. PTH, dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP), or vehicle was administered intravenously. In 9-day-old birds, urinary cAMP and inorganic phosphate excretion fell dramatically after calcium loading and rose significantly after PTH, DBcAMP, or EGTA administration. These manipulations had no significant effect on excretion of calcium or inorganic phosphate in 1-day-old hatchlings. Five day-old-chicks gave an intermediate response. All three age groups, as well as 15-day-embryos, showed sharp increases in urinary cAMP values after PTH administration. Thus the adult response pattern to PTH appears to develop gradually during the first week after hatching or to be suppressed during the perinatal period, whereas the second-messenger response to the hormone, indicating hormone-receptor interaction, is present from late embryogenesis onward.

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Plasmalemma localisation of inorganic phosphate in B cells pancreas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083515 ◽

1978 ◽

Vol 36 (2) ◽

pp. 528-529

Author(s):

F. B. P. Wooding ◽

K. Pedley ◽

N. Freinkel ◽

R. M. C. Dawson

Keyword(s):

Electron Microscope ◽

B Cells ◽

B Cell ◽

Pancreatic Islets ◽

High Glucose ◽

Lead Acetate ◽

Inorganic Phosphate ◽

Slight Modification ◽

Uranyl Acetate ◽

Lead Phosphate

Freinkel et al (1974) demonstrated that isolated perifused rat pancreatic islets reproduceably release up to 50% of their total inorganic phosphate when the concentration of glucose in the perifusion medium is raised.Using a slight modification of the Libanati and Tandler (1969) method for localising inorganic phosphate by fixation-precipitation with glutaraldehyde-lead acetate we can demonstrate there is a significant deposition of lead phosphate (identified by energy dispersive electron microscope microanalysis) at or on the plasmalemma of the B cell of the islets (Fig 1, 3). Islets after incubation in high glucose show very little precipitate at this or any other site (Fig 2). At higher magnification the precipitate seems to be intracellular (Fig 4) but since any use of osmium or uranyl acetate to increase membrane contrast removes the precipitate of lead phosphate it has not been possible to verify this as yet.

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