Sidney L. Dale

Diagnosis and localization of aldosterone-producing adenomas by adrenal-vein cateterization.

EVEN when the diagnosis of primary aldosteronism is obvious before operation, there is no way to localize the adenoma. Preoperative demonstration of the tumor radiographically, as by retroperitonea...

Simplified radioimmunoassay for aldosterone using antisera to aldosterone-γ-lactone

Abstract A simplified, non-chromatographic method for aldosterone-γ-lactone (2) radioimmunoassay is described, using a high titer aldosterone-γ-lactone antibody. This method takes six working hours for completion; the blanks are below the sensitivity of the assay (0–10 pg), and the intra and interassay coefficient of variation is 4.9% and 8.2% respectively. There is no significant variation with different plasma volumes assayed and the plot of added and assayed aldosterone gives a slope of 0.983. The negligible cross reactivity with other steroids and lactones eliminates the problem of interference by these substances.

18-Hydroxy-Deoxycorticosterone in Human Hypertension

18-Hydroxy-ll-deoxycorticosterone (18-OH-DOC) was isolated from human adrenal vein blood in concentrations of the same magnitude as is aldosterone, and its structure was proved by a variety of methods including mass spectral analysis. Angiotensin infusions failed to evoke a rise in 18-OH-DOC secretion, whereas ACTH increased 18-OH-DOC secretion up to 20-fold. The secretion rate of 18-OH-DOC determined by isotope dilution in healthy subjects was similar to the range of aldosterone secretion. Excretion of the ring A reduced glucuronide metabolite, 18-hydroxy-tetrahydro-deoxycorticosterone (18-OH-TH DOC), in urine proved to be a valid index of secretion of 18-OH-DOC. 18-OH-DOC secretion was estimated in a variety of hypertensive disorders and found to be significantly elevated in a few (3 of 12) patients with essential hypertension, suppressed plasma renin activity, low or normal aldosterone secretion, and who had significant reduction in blood pressure with spironolactone. A single patient became normotensive on prolonged dexamethasone suppression of ACTH and 18-OH-DOC secretion. The possibility that 18-OH-DOC is a precursor of some more oxygenated and, perhaps, more active mineralocorticoid is suggested.

Activation of aldosterone secretion in primary aldosteronism

Angiotensin infusion evokes marked increases in aldosterone secretion in primary aldosteronism and little change in secondary aldosteronism. The low plasma renin activity of primary aldosteronism and the elevated plasma renin activity of secondary aldosteronism are thought to account for this differential response. The effect of angiotensin on aldosterone and 18-hydroxycorticosterone secretion was studied during adrenal vein catheterization in seven patients with primary aldosteronism (whose plasma renin activity had been elevated following spironolactone therapy), one hypertensive patient with normal plasma renin activity and normal aldosterone secretion, two patients with secondary aldosteronism who had elevated plasma renin activity, and one anephric patient whose plasma renin activity was 0. Adrenal venous aldosterone and 18-hydroxycorticosterone were measured before and after a ten min sub-pressor angiotensin infusion. The cells of the aldosterone-producing adenoma (APA) respond to small increases in plasma angiotensin with large increases in secretion of aldosterone and 18-hydroxycorticosterone. The dose of angiotensin capable of evoking this response from the aldosterone-producing adenoma produces little or no change in the secretion of the steroids from nontumorous glands. The augmentation of aldosterone secretion, induced by angiotensin, in primary aldosteronism is due solely to increased secretion by the adenoma and not by the contralateral zona glomerulosa. The increased sensitivity of the aldosterone-producing adenoma is characteristic of the tumor. This response is independent of fluctuations in endogenous plasma renin activity. This sensitivity is not blunted by high plasma renin activity, nor is it a function of tumor mass for the effect is observed in aldosterone-producing adenomas regardless of size. ACTH injection after angiotensin infusion resulted in a marked increase in aldosterone concentration in the effluent from the nontumorous adrenal, but was not capable of producing further increases in aldosterone concentration in the effluent from the APA. In view of this exquisite sensitivity to infused angiotensin, it may be that the small variations in endogenous plasma renin activity that have been observed in primary aldosteronism may be capable of evoking large changes in aldosterone secretion in patients with aldosterone-producing adenomas.

The measurement of urinary tetrahydroaldosterone by radioimmunoassay.

Abstract A simple and specific radioimmunoassay is described for measuring urinary tetrahydroaldosterone (THAldo). The antiserum used is highly sensitive to aldosterone lactone, but is sufficiently sensitive to tetrahydroaldosterone lactone when the antibody dilution is reduced from 1:500,000 to 1:20,000. Specific activities of urinary THAldo determined by the radioimmunoassay were in close agreement with values obtained by a colorimetric method (r = 0.966). Subjects treated with ACTH showed a transitory increase in THAldo excretion when THAldo was quantitated by the radioimmunoassay. These findings differ from the sustained increase in THAldo excretion in response to ACTH reported on previously by this laboratory during a time when a colorimetric method was used to measure THAldo. The radioimmunoassay appears to be more specific than the colorimetric method when steroidogenesis is increased with ACTH. The measurement of urinary THAldo excretion by radioimmunoassay serves as a useful alternative to the more time consuming colorimetric procedures.

Adrenal steroidogenesis in "low renin" or hyporeninemic hypertension.

Abstract Suppressed plasma renin activity (PRA) and volume dependent hypertension have been associated with adrenocortical structural abnormalities, excessive deoxycorticosterone, 18-hydroxydeoxycorticosterone (18-OH-DOC) hypersecretion or non-suppressible aldosterone secretion and may be observed in patients thought to have “essential” hypertension. Dale and Melby (1973) encountered an additional alteration in steroid metabolism in two such patients while studying steroidogenesis in vitro by their sectioned adrenals. Conversion of labeled 18-OH-DOC to a new structure 16α,18-dihydroxydeoxycorticosterone was demonstrated to be greatly accelerated by the adrenal tissue in these patients as compared to normal adrenal tissue (70–80% vs 15% conversion). Hypersecretion of 16α,18-dihydroxy-deoxycorticosterone occurred in each. This steroid exerted no effect on sodium metabolism in adrenalectomized rats and in the toad bladder assay, but markedly enhanced activity of subthreshold doses of aldosterone in reducing sodium excretion in urine of adrenalectomized rats. We have concluded that excessive 16α,18-dihydroxydeoxycorticosterone secretion may be important in the genesis of suppressed renin in some patients with hypertension because of the unique activity of this steroid which appears to function as a cooperative or positive allosteric effector of aldosterone.

Isolation and identification of 16α, 18-dihydroxydeoxycorticosterone from human adrenal gland incubations

Abstract Incubations of 1,2- 3 H-18-hydroxydeoxycorticosterone with human adrenal glands resulted in conversion to a more highly hydroxylated material in addition to other material. By derivative formation, gas chromatography — mass spectrometry, and nuclear magnetic resonance spectroscopy, the structure of this material was shown to be 16 α , 18-dihydroxydeoxycorticosterone. Possible biological activity of this compound is discussed.

New mineralocorticoids and adrenocorticosteroids in hypertension

Alterations in steroidogenesis have been demonstrated in experimental and human hypertension. It is highly likely that increased secretion of the nonaldosterone mineralocorticoid deoxycorticosterone (DOC) and 18-hydroxy-11-deoxycorticosterone (18-OH-DOC) may initiate or perpetuate hypertension, or both. It is possible that 16 beta-hydroxydehydroeplandrosterone (16beta-OH-DHEA) directly induces the hypertensive process in animals. The significance of the findings of increased secretion of 16 alpha, 18-dihydroxy-11-deoxycorticosterone (16alpha, 18-diOH-DOC) and dehydroepiandrosterone sulfate (DHEA-S) cannot now be appreciated. Neither has been examined experimentally for its ability to induce hypertension, and the former compound is not a mineralocorticoid. It does possess the curious property of increasing mineralocorticoid activity of other steroids, by altering either their metabolism or mode of action. Variations in the mineralocorticoid hypertensive syndrome or, more aptly, the steroid hypertensive syndrome could account for the hypertension in a substantial portion of patients with reduced plasma renin activity.

Peripheral plasma steroid concentrations in rats sacrificed by anoxia

Abstract The plasma concentrations of corticosterone, 18-hydroxy-11-deoxy-corticosterone, deoxycorticosterone, and aldosterone were determined in salt drinking male rats sacrificed by nitrogen gas with and without prior ether stress. The concentrations obtained in the unstressed rat sacrificed in this manner at 0800 h were: corticosterone 0.64 μg/dl, 18-hydroxy-11-deoxycorticosterone 0.43 μg/dl, deoxycorticosterone 10.1 nmg/dl and aldosterone 6.51 ng/dl. Those obtained in the rat at 0800h stressed by ether prior to sacrifice by nitrogen gas were: 15.7μg/dl, 7.2μg/dl, 23.9 ng/dl and 26.1 ng/dl respectively. In samples obtained at 1830 in rats sacrificed using the same procedure as the unstressed animals the concentrations were: corticosterone 5.8μg/dl, 18-hydroxy-11-deoxycorticosterone 0.73μg/dl, aldosterone 19.6 ng/dl and deoxycorticosterone 13.2 ng/dl. The basal value of corticosterone obtained in the female rat at 0800 h sacrificed in the same manner as the male animal was: 0.84 ± 0.16μg/dl. Renal tissue corticosterone concentrations were also measured under these conditions of sacrifice.

Temporal relationships among the excretory patterns of 2-hydroxyestrone, estrone, estradiol, and progesterone during pregnancy in the rat

The urinary excretion pattern of 2-hydroxyestrone, estradiol, estrone, and progesterone was examined in rats during early, mid, and late pregnancy. Progesterone increased from early to mid pregnancy and declined significantly 2 to 3 days prior to parturition, corresponding to changes observed in blood levels by others. 2-Hydroxyestrone, the major estrogen in rat urine, increased significantly 4 days prior to delivery and remained elevated until it further increased sharply the day of parturition. Urinary estradiol and estrone levels showed little change until the day of parturition, when they increased significantly. Multiple correlation analysis of the data implied that 2-hydroxyestrone and estradiol were negatively correlated at the time of implantation. The results suggest that catechol estrogens, through their effect on prostaglandin synthesis, may participate in the process of implantation as well as in the mechanism involved in the onset of labor.