EFFECT OF HIGH CALCIUM INTAKE ON STRONTIUM85 METABOLISM IN MAN*

Abstract

The prolonged use of orally administered Ca was studied on radiostrontium absorption and excretion in man. Sr85 was given as the tracer by the oral or intravenous route. The duration of the calcium gluconate administration ranged from 3 to 691 days before the Sr85 studies were performed during high Ca intake. The absorption of Sr85 from the intestine was of similar magnitude in 7 of 11 patients during low and high Ca intake and was somewhat lower in 4 patients. The addition of Ca to the diet led to an increase of urinary Ca excretion in most patients studied, which was accompanied by a somewhat higher urinary radiostrontium excretion after intravenous doses of Sr85, while the urinary Sr85 excretion generally did not increase following the oral administration of the tracer.