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Search for other papers by V. H. T. JAMES in
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SUMMARY
A double isotope derivative assay technique for the simultaneous estimation of aldosterone, corticosterone and cortisol in human peripheral plasma is described. With this method, concentrations of the corticosteroids in plasma from adrenalectomized subjects were not significantly different from zero. Further evidence of specificity for aldosterone was obtained by measuring the disappearance rate of a single intravenous injection of unlabelled aldosterone from peripheral plasma, by demonstrating a rapid rise in aldosterone concentration in normal subjects acutely depleted of sodium, and by a comparison of aldosterone levels in patients with primary aldosteronism before and after surgical treatment. A study has also been made of the variation of the ratio of cortisol to corticosterone in normal subjects and of the effect upon this ratio of corticotrophin administration and haemorrhage.
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The urinary excretion levels of individual 17-oxosteroids in eight patients with Cushing's syndrome have been determined quantitatively. Using these values approximate secretion rates of cortisol and 11β-hydroxyandrostenedione were calculated and found to be elevated above the normal range. The excretion values for 11-deoxy-17-oxosteroids were highly variable, being below normal, normal or elevated in different patients. The excretion patterns in adrenocortical hyperplasia and carcinoma showed no characteristic differences; however, the patients with adrenal adenoma showed steroid excretions which suggested that these tumours secreted cortisol almost exclusively, together with small quantities of 11β-hydroxyandrostenedione, and minimal amounts of 11-deoxy-C19-steroids. The majority of patients excreted aetiocholanolone and androsterone in an abnormally high ratio; this also occurred after administration of androst-4-ene-3:17-dione, and it is suggested that in Cushing's syndrome the hepatic enzymes preferentially reduce adrenal androgen to metabolites with the 5β configuration.
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SUMMARY
The urinary excretion of individual 17-ketosteroids by a series of eighteen normal female subjects has been determined using enzyme hydrolysis and quantitative paper chromatography. The results are compared with those obtained by other workers, and their significance is discussed. In two cases, the results of stimulation with adrenocorticotrophic hormone were studied; the most striking effect was a disproportionate increase in the excretion of dehydroepiandrosterone.
Search for other papers by HANNELORE BRAUNSBERG in
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Search for other papers by V. H. T. JAMES in
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SUMMARY
A simple method for the determination of cortisol in human plasma has been improved and studied in detail. The specificity for cortisol was increased by an additional partition of the extract between benzene and water. This did not obviate the use of a preliminary petrol partition to remove some material interfering with the determination. Quenching or potentiation of fluorescence by impurities is common, and an 'internal standard' technique, consisting of addition of cortisol to parallel plasma samples, was adopted in an attempt to improve the accuracy of the method. Careful cleaning of all glassware is essential for satisfactory accuracy. A preliminary estimate of precision indicates that plasma cortisol concentrations of 2 μg./100 ml. are distinguishable from zero, but satisfactory precision (error ≤ 15%, P = 0·05), at concentrations of 10 μg./100 ml. or greater, still requires samples of 8 ml. of plasma.
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Search for other papers by V. H. T. JAMES in
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SUMMARY
A method has been described for the extraction, chromatographic purification and fluorimetric determination of cortisol and corticosterone from human peripheral blood plasma. Data are presented on specificity, sensitivity, precision and accuracy, and results for normal individuals and persons with adrenal hyperfunction are given and discussed.
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Search for other papers by J. LANDON in
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Search for other papers by V. WYNN in
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SUMMARY
Adrenocortical suppression tests, based on the fall in urinary 17-hydroxy-corticosteroid excretion during the oral administration of dexamethasone, were found to be of value in the diagnosis of Cushing's syndrome, but less useful in differentiating bilateral adrenal hyperplasia from adrenal tumour. Such tests have the disadvantage of requiring accurate urine collections and of taking several days to perform. A test is described, based on the decrease in plasma cortisol concentration during i.v. infusion of dexamethasone at a rate of 1 mg./hr. The results obtained in 12 patients with Cushing's syndrome and bilateral adrenal hyperplasia differed from those found in control subjects in that there was a delay between the start of the infusion and the fall of plasma cortisol, and the rate of fall was less rapid. The values found after 180 min., expressed either as μg./100 ml. or as a percentage of the resting level, differed significantly (P < 0·001) in the two groups. The test proved valuable as an aid to the diagnosis of Cushing's syndrome, was easy to perform, and could be completed in 3 hr.
In some patients with Cushing's syndrome, the administration of synthetic glucocorticoids appeared to result in an increased urinary steroid excretion. A transient increase in plasma cortisol levels was also observed in some of these patients during the early period of dexamethasone infusion. It is thought that this finding reflects an alteration in steroid metabolism induced by dexamethasone and fluorocortisol.
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Search for other papers by V. WYNN in
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Search for other papers by V. H. T. JAMES in
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SUMMARY
The adrenocortical response to stress as shown by an increase of the plasma cortisol concentration during insulin-induced hypoglycaemia has been studied. The response was found to depend upon the degree and duration of the hypoglycaemia and upon the integrity of the entire hypothalamo-pituitary-adrenal axis. Thus, there was no response in subjects in whom the blood sugar did not fall below 40 mg./100 ml., nor in patients with severe hypothalamic or pituitary disorders.
The test was quick and simple to perform and did not require admission to hospital; it would seem to be of considerable value in the investigation of patients with suspected endocrine disease.
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Search for other papers by V. H. T. JAMES in
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SUMMARY
The effect of methandienone administration on urinary steroid excretion has been studied in subjects with normal pituitary-adrenal function and in patients with various endocrine diseases.
In the control subjects, a marked suppression of urinary 17-KS and 17-OHCS excretion occurred, which persisted throughout even prolonged periods of methandienone administration. Upon cessation of methandienone treatment a prompt rise in urinary steroid excretion occurred, on occasions to levels slightly higher than those seen before treatment.
Similar results were obtained in subjects with acromegaly and Cushing's syndrome, but in patients with anorexia nervosa and a low basal steroid excretion, the suppressive effect of methandienone was less marked.
During treatment with methandienone, pituitary response to metopirone was depressed, but adrenal response to corticotrophin was unaltered.
It was concluded that methandienone diminishes the rate of production of adrenocortical steroid by inhibiting corticotrophin production or release. Unlike the inhibition observed during treatment with glucocorticoids, it was not associated with atrophy of the adrenal glands.
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Search for other papers by R. P. MICHAEL in
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Few data are available on the metabolism of progesterone in infra-human primates. Using gas chromatography, Chamberlain, Knights & Thomas (1964) detected 5β-pregnane-3α,20α-diol in the urine of pregnant rhesus monkeys and in the urine of a male injected with a large dose of progesterone, although quantitative data were lacking. While it would appear that the metabolism of progesterone in an anthropoid ape, such as the chimpanzee, is similar to that in man (Romanoff, Grace, Sugarman & Pincus, 1963), the observations of Jeffery (1966) have indicated that this may not be the case in a catarrhine monkey. We have therefore studied the excretion of progesterone metabolites in the urine and faeces of the rhesus macaque (Macaca mulatta).
Five adult, female rhesus monkeys (4·6–7·1 kg. body weight) each received approximately 25 [4-14C]progesterone i.v. (Table 1), and were then placed either in primate restraining chairs or metabolism cages in order to make
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Search for other papers by V. H. T. JAMES in
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Search for other papers by R. P. MICHAEL in
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SUMMARY
Labelled progesterone was administered intravenously to five, adult female rhesus monkeys and urine and faeces were collected every 24 h. Excretion of radioactivity in urine occurred most rapidly in the first 24-h period and then declined exponentially. The excretion of radioactivity in faeces reached maxima during the 2nd, 3rd or 4th 24-h periods depending on the animal studied. 76–94% (mean 86%) of the radioactivity administered was recovered within 9 days, but small quantities continued to be excreted in urine up to 16 days after injection. Generally, greater amounts of radioactivity were recovered from faeces (41–57%) than from urine (26–48%). Using different hydrolytic and extraction procedures, some 50% of the radioactivity in urine was recovered in the neutral extracts. The major metabolite in urine was androsterone which accounted for 1·1–12·2% (mean 6·0%) of the progesterone administered. Pregnanediol was not an important urinary catabolite in this species. Differences in the extent to which progesterone is metabolized to C-19 compounds in macaques, baboons, great apes and man may reflect the phylogeny of a catabolic desmolase system in anthropoid primates.
