Clinical Applications of Aldosterone In Vivo Secretion Rate

Abstract

Several investigators have described procedures for the indirect measurement of the aldosterone secretion rate in man [^1–5]. The general method is dependent on intravenous administration of a dose of radioactive aldosterone, the resultant in vivo dilution of the tracer by endogenous steroid, and measurement of this dilution by isolation of a specific metabolite fraction from the urine excreted during a measured time interval. The process of dilution is influenced by the presence of a body pool of steroid at the beginning and end of the study. The apparent secretion rate is therefore more representative of the amount of steroid removed rather than that secreted during the chosen time period. Despite these and other factors, the method has become useful as an approximation of secretion rate. The methods in current use differ mainly in the metabolite fraction chosen, the purification method, and the means of measurement of total steroid in the isolated sample. This discussion will be based on the method of Peterson [²]

Presented at the Sixth Symposium on Advances in Tracer Methodology, November, 1962.