Movement of Strontium in the Human Body

Journal Article · Sat Sep 22 00:00:00 EDT 1962 · BMJ

DOI:https://doi.org/10.1136/bmj.2.5307.773· OSTI ID:4747667

Carr, T. E. F.; Harrison, G. E.; Loutit, J. F.; Sutton, A.

The replacement of body strontium was investigated in single-dose experiments by injecting Sr⁸⁵ (0.5 mu C), a gamma emitter, intravenously into 2 normal subjects and following its loss from plasma for 2 days, its excretion for 4 months, and, with a whole-body counter, its retention for 1 year. Retention was not expressed as a simple exponential function but presumably the sum of many. After a few weeks it could be expressed as a power-function. From the loss of Sr⁸⁵ from plasma in the first week it was possible to deduce an exchangeable pool of about 2.75 mg of Sr and clearance into bone of 0.4 mg/day. However, the 0.4 mg/ day value was not used to calculate turnover, because while the calculation is valid for exchange mechanisms it may not be applicable to osteogenesis. About 85% of the injected isotope was excreted within the year; the remaining 15% was retained in definitive, as distinct from temporary, bone. Normally about 20% of dietary Sr (about 2 mg/day in the United Kingdom) is absorbed. Therefore replacement of Sr in bone is about 0.2 x 2 x 365 x 0.15 = 22mg/ yr. In daily-dose experiments, 3 human subjects ingested 0.5 mu C of Sr⁸⁵ daily for a month. Equilibrium was established within a week, when plasma levels were constant: 3, 7, and 3 m mu C/l, respectively; and daily urine excretions were constant: 25, 60, and 50 m mu C/day, so that renal clearances from plasma were approximately: 8, 8, 17 l/day. Balances in the second to fourth weekiy periods indicated a final retention of approximates 6% of ingested isotope. Estimates of the annual rate of replacement in the adult are only a few per cent per year, when calculated from long-term ingestion of Sr⁹⁰, somewhat more according to short-term experiments involving ingestion of Sr/sup 85/ for a month, and much less than the total turnover of bone mineral.

• Research Organization: Medical Research Council, Harwell Berks, Eng.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-017718
• OSTI ID: 4747667
• Journal Information: BMJ, Journal Name: BMJ Journal Issue: 5307 Vol. 2; ISSN 0959-8138
• Publisher: BMJ Publishing Group
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BLOOD PLASMA
BONES
COUNTERS
EMISSION
GAMMA RADIATION
MAN
METABOLISM
STRONTIUM
STRONTIUM 85
TRACER TECHNIQUES
URINE