URINARY EXCRETION OF CALCIUM AND STRONTIUM-85 IN MAN

Journal Article · Tue May 01 00:00:00 EDT 1962 · Journal of Applied Physiology (U.S.) Changed to J. Appl. Physiol.: Respir., Environ. Exercise Physiol.

OSTI ID:4774195

Samachson, J; Spencer-Laszle, H

The extent to which the urinary excretion and renal clearance of Sr/sup 85/ can be related quantitatively to the excretion and clearance of stable Ca was investigated. Urinary Sr/sup 85/ and Ca excretions were compared in 45 patients after intravenous or oral administration of Sr/sup 85/. Although correlations were found between Sr/sup 85/ and Ca excretions, there was a wide range of Sr/sup 85/ excretions at a given Ca excretion. In general, patients with a urinary Ca of 300 mg/day excreted from 50 to 60% of an intravenous Sr/sup 85/ dose in 12 days, as contrasted with an Sr/sup 85/ excretion of 15-25% in patients excreting 40 mg Ca/day. The best correlation appeared to be between Sr/sup 85/ and Ca clearances. Empirical equations and curves are given to permit an estimate of urinary Sr/sup 85/ excretion from Ca excretion. The renal tubular reabsorption of Ca was greater than that of Sr/sup 85/ in all patients, whether Ca excretion was low or high. As tubular reabsorption becomes less efficient, the Sr/sup 85/ clearance and Ca clearance increase together, but not in the same proportion, the ratio of Sr/sup 85//Ca clearance decreasing. As the clearances represent that portion of Sr/sup 85/ and of Ca in the glomerular ftltrate which escapes reabsorption, it would appear that, with decrease in the efficiency of tubular reabsorption, discrimination between 2 ions becomes less. However, the ratio of the calculated reabsorption of Ca/ Sr/sup 85/ increased from 1.008 to 1.04. It is uncertain whether the ratio of Sr/sup 85//Ca clearance or the relative reabsorption of Ca/Sr/sup 85/ better expresses the extent of renal discrimination in favor of Ca. (H.H.D.)

• Research Organization: Montefiore Hospital, New York
• NSA Number: NSA-17-001217
• OSTI ID: 4774195
• Journal Information: Journal of Applied Physiology (U.S.) Changed to J. Appl. Physiol.: Respir., Environ. Exercise Physiol., Journal Name: Journal of Applied Physiology (U.S.) Changed to J. Appl. Physiol.: Respir., Environ. Exercise Physiol. Vol. Vol: 17; ISSN JAPYA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BIOLOGY AND MEDICINE
BLOOD VESSELS
CALCIUM
DIAGRAMS
DIFFUSION
EQUATIONS
IONS
KIDNEYS
MAN
MATHEMATICS
MEMBRANES
PHYSIOLOGY
QUANTITY RATIO
STOMACH
STRONTIUM 85
TISSUES
URINE