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This article reports that several monovalent cations have been shown to influence aldosterone secretion by a direct action on the adrenal cortex. Adrenal arteroid infusion of KCI or a local reduction of sodium concentration in adrenal arterial plasma cause an increase of aldosterone secretion in the conscious sheep. Caesium and rubidium have been shown to increase aldosterone production in vivo and in vitro. Variation of dietary intake of magnesium or variation of plasma level of calcium due to disease, infusion of calcium or chelating agents affect renal excretion of sodium and potassium.

This article studies the effect of nephrectomy on aldosterone secretion in the conscious sodium-depleted hypophysectomized sheep. The possibility emerged that in these animals under acute experimental conditions some factor other than the pituitary, the kidney and plasma electrolytes was operative in sustaining aldosterone hyperseeretion. The studies reported in this article were designed to examine the effect of nephrectomy on aldosterone secretion when the animals were conscious and maintained under conditions as nearly normal as was feasible.

This article presents information regarding the role of circulating fluid volume and related physiological parameters in the control of aldosterone secretion. The precise role of the volume of the circulating blood in the control of aldosterone secretion remains obscure. Early studies, based on urinary aldosterone excretion, suggested existence of a definite relationship between these variables, but the subsequent observations that the hypersecretion of aldosterone due to hemorrhage and thoracic inferior caval constriction was not usually reversed by correction of the circulating blood volume, together with the presence of normal or increased blood volume in many clinical states of hyperaldosteronism, have led to a situation which is confused and in need of reappraisal.

Describes a double isotope dilution derivative method for the determination of aldosterone, cortisol, and corticosterone in adrenal vein blood of sheep. Use of 14C-labeled steroids as the indicator and ³H-acetic anhydride as the reagent for the formation of the labeled derivative; Mean secretion rates of aldosterone, cortisol and corticosterone from sodium replete and sodium deficient sheep with autotransplanted adrenals.

Studies the effect of increased adrenal arterial sodium concentration during an established large sodium deficit sleep with a sustained high aldosterone secretion. Same procedure at the onset of sodium deficiency when aldesterone secretion was beginning to increase from basal; Alternative interpretation that the increased plasma sodium concentration to some extent antagonized the effect of the non-ionic humoral stimulus of aldosterone secretion.

The article informs about the estimation of testosterone in biological fluids. It further describes a method for the estimation of testosterone in urine. This is a double isotope dilution derivative procedure similar to the method for the estimation of testosterone in peripheral plasma. Testosterone was found in three fraction from urine. In the free fraction extracted at neutral PH 1 fraction in which testosterone is released after incubation with mineral acid at PH 1 at 40 degree Celsius, and following incubation with glucoronidase.

A method is described for the estimation of free testosterone in human peripheral plasma. This method which uses the double isotope dilution derivative principle with C14testosterone as marker steroid, H3-acetic anhydride as deriving agent, shows normal male levels to range from 0.49-0.98 μg./100 ml. and females from less than 0.05 μg./100 ml. to 0.31 μg./100 ml. The results obtained by this method have been compared with those given by other techniques for the estimation of this steroid hormone. [ABSTRACT FROM AUTHOR]