Radioimmunoassay of 17-hydroxyprogesterone in serum with or without thin-layer chromatographic purification.

A radioimmunoassay for the measurement of 17-hydroxyprogesterone (17-OHP) is described. The antigen 11-desoxycortisol-21-hemisuccinate-bovine serum albumin has been used to produce two antisera of different antibody populations in the same animal. The thin-layer chromatographic system described can be used to separate all the cross-reacting steroids investigated from 17-OHP. A simplified method is also presented using preliminary solvent extraction only. The mean 17-OHP levels measured, using this method, were, for normal men, 0.86 +/- 0.19 ng/ml (SD), for normal females 0.30 +/- 0.19 ng/ml in the follicular phase and 1.72 +/- 0.18 ng/ml in the luteal phase of the menstrual cycle, and 0.45 +/- 0.17 ng/ml in normal postmenopausal women.     

An adrenocortical tumor secreting weak mineralocorticoids

An adrenocortical carcinoma (15.5 g) secreting excessive amounts of steroids with weak mineralocorticoid activity in a 25-year-old woman was studied with particular reference to its in vivo and in vitro secretions of steroids. Severe hypertension, occasional low serum potassium and suppressed PRA were the major clinical findings, and were improved with removal of the tumor. In the preoperative stage, plasma levels of 11-deoxycorticosterone, 18-hydroxy-11-deoxycorticosterone, corticosterone and 18-hydroxycorticosterone were all increased. However, the plasma level of aldosterone was repeatedly normal. Although plasma levels of pregnenolone, 17-hydroxypregnenolone, progesterone and 17-hydroxyprogesterone were very high, those of other late step steroids, i.e. 11-deoxycortisol, cortisol, dehydroepiandrosterone, androstenedione and testosterone were almost normal. From these findings, a major etiological role of weak mineralocorticoids such as 11-deoxycorticosterone, 18-hydroxycorticosterone and corticosterone in her hypertension was suggested. Pregnenolone and 17-hydroxypregnenolone in tumor tissue were increased, but 11-deoxycorticosterone, corticosterone, aldosterone, cortisol and adrenal androgens such as dehydroepiandrosterone, androstenedione and testosterone were below normal or low normal. In vitro production of 11-deoxycorticosterone, aldosterone or cortisol by the tumor tissue slices was very low and scarcely responded to synthetic ACTH.     

Changes in steroid pattern following acute and chronic adrenocorticotropin administration in premature adrenarche

Biochemically adrenarche is characterized by increased production of 5-ene steroids, in particular Dehydroepiandrosterone (DHA) and its sulphate (DHA-S). It is still not clear if ACTH is responsible for this adrenal steroid production. The aim of the present study was to evaluate the effect of acute and chronic ACTH administration, without dexamethasone pretreatment, on hormonal patterns in 20 patients (5 males aged between 6 8/12 and 7 10/12 years and 15 females aged between 5 9/12 and 7 6/12 years) with idiopathic premature adrenarche. Pregnenolone (5P), DHA, DHA-S, 17-hydroxyprogesterone (17-OHP), androstenedione (A), 11-deoxycortisol (S) and cortisol (F) have been determined by Radioimmunoassay. The results of the hormonal evaluation (means +/- standard error) showed high plasma levels of DHA [329.2 +/- 41.7 ng/100 ml (dl)] and DHA-S (169.1 +/- 54 micrograms/dl) and slightly increased levels of 5P (74.4 +/- 7.1 ng/dl), of A (45.4 +/- 4.6 ng/dl) and 17-OHP (69.3 +/- 11.3 ng/dl) in comparison to those of controls, thus indicating a decrease in 3 beta-hydroxysteroid dehydrogenase activity and an increase in 17-20-lyase and 17-hydroxylase activities, characteristic for adrenarche. Acute and chronic ACTH stimulation did not amplify the characteristic basal hormonal pattern, but they induced a shift of adrenal steroid metabolism to 4-ene pathway, suggesting that the basal hormonal pattern in premature adrenarche may be independent or, at least, not exclusively dependent on ACTH control.     

17,20-desmolase deficiency in a female newborn, paradoxically virilized in utero

The patient was born with ambiguous genitalia (stade III of Prader). The karyotype revealed a normal female genotype. A defect in 21-hydroxylase, at first suspected, was denied by the hormonal studies. Indeed, extremely high levels of pregnenolone, pregnenolone sulfate, progesterone were found in association with low plasma levels of delta 4-androstenedione, testosterone, dehydroepiandrosterone and its sulfate, while cortisol 17OH-progesterone and ACTH levels and plasma renin activity were normal. The hormonal pattern was thus consistent with 17,20-desmolase deficiency. The dynamic studies further supported this contention: all the progestagens rose further after ACTH stimulation and were suppressed by dexamethasone. Meanwhile, all androgens failed to rise after ACTH: the responses of cortisol were normal. The in utero virilization of the female fetus was not understood until an history of virilization was allegedly found in the mother (luteoma of pregnancy). This is the first case of 17-20 desmolase defect recognized in a female newborn. This child, born with ambiguous genitalia had presented the concurrence of two very rare conditions. The in utero virilization of maternal origin enabled us to make the diagnosis of the 17-20 desmolase defect, which otherwise would have been ignored in a XX subject in the neonatal period because it would obviously be unsymptomatic at this age.     

Effect of acute ACTH administration on plasma steroid levels in the dog

Production of adrenal steroids in intact and castrated dogs is stimulated acutely by ACTH. While the increase in plasma cortisol, 17-hydroxypregnenolone and 17-hydroxyprogesterone is not affected by castration, the increment of dehydroepiandrosterone is totally abolished. On the other hand, administration of 17-hydroxypregnenolone in adrenalectomized dogs caused an increase in plasma C-19 steroids such as dehydroepiandrosterone, androstenedione and testosterone indicating that this C-21 progestin in plasma is rapidly converted. The site of this conversion is likely the testis. Furthermore, acute hCG administration in adrenalectomized dogs resulted in a marked increase in the levels of plasma 17-hydroxypregnenolone and dehydroepiandrosterone. However, our data show an ACTH-induced rise in 5-androstene-3 beta. 17 beta-diol in intact and castrated dogs, thus suggesting that this steroid is a good parameter to assess in the stimulation of adrenal steroidogenesis by ACTH.     

Comparison of saliva and plasma 17-hydroxyprogesterone time-course response to hCG administration in normal men

17-Hydroxyprogesterone (17-OHP) time-course response to hCG (5000 IU) was studied simultaneously in the saliva and the plasma of 12 adult healthy men. Baseline levels in plasma and saliva were: 1.0 +/- 0.1 ng/ml (mean +/- SEM) and 24 +/- 2 pg/ml respectively. After hCG, a biphasic pattern was observed in both fluids with a similar early response but the peak elicited at 33 h in plasma was not observed in saliva where the levels were lower than those recorded at 24 h. Since saliva steroids are believed to reflect the plasma non-protein bound fraction, this difference was assumed to be due to the decrease of the unbound fraction of plasma 17-OHP in the late afternoon as a consequence of the increase of CBG-bound fraction since at that time cortisol levels are low. The ratio of saliva to plasma 17-OHP levels was significantly correlated with plasma cortisol levels: r = 0.44 (P less than 0.01; n = 140). However the similar response in saliva at 24 and at 48 h after hCG allows the evaluation of the endocrine testicular function using saliva instead of plasma.     

Effects of insulin-like growth factor I (IGF-I) on enzymatic activity in human adrenocortical cells. Interactions with ACTH

Cells obtained from 6 adult human adrenals or adrenal fragments were cultured in serum-free synthetic medium (McCoy's) in order to study the isolated effects of IGF-I on steroidogenesis and its interactions with ACTH. After addition of peptide, changes in the activities of steroidogenic enzymes were assessed by measuring certain steroids in the spent medium. These included pregnenolone, 17-hydroxypregnenolone (17-OH-Preg), dehydroepiandrosterone (DHA), 17-hydroxyprogesterone (17-OH-P), androstenedione (AD), 11-deoxycortisol and glucocorticoids (chiefly cortisol and its immediate precursors, 11-deoxycortisol and 17-OH-P) and cortisol itself.

The steroid responses obtained with repeated doses of IGF-I (40 ng/ml ≈ 10⁻⁹ M), added at 0, 48 and 72 h, over 4 days' culture were quite different from those obtained with repeated doses of ACTH (0.25 ng/ml ≈ 10⁻¹⁰ M). All the steroids measured increased with time of culture under the influence of ACTH and, apart from pregnenolone which peaked, tended to reach a plateau. With IGF-I, by contrast, DHA, AD, 11-deoxycortisol and glucocorticoid production increased initially, then decreased progressively, whereas pregnenolone, 17-OH-Preg and 17-OH-P production was either absent or negative.

Cumulative steroid production over 4 days reached similar levels in response to a single dose of IGF-I and/or ACTH, with two major exceptions: pregnenolone dropped significantly with IGF-I [46% ± 6 (SEM) as opposed to 93% ± 11 with ACTH, P < 0.005, N = 5], as did 17-OH-P (48% ± 11 vs 113% ± 8 with ACTH, P < 0.001, N = 6). Increased formation of down-stream metabolites (DHA, AD, 11-deoxycortisol and glucocorticoids) would suggest that IGF-I induced stimulation of the 17-, 21- and 11β-hydroxylases.

The responses to ACTH stimulation of cells which 4 days previously had been pre-treated with an initial and single dose of IGF-I and/or ACTH emphasized the impact of IGF-I on the 3-hydroxylation steps in cortisol biosynthesis. Compared with ACTH pre-treatment, the effects of which faded in the long term, pre-treatment with IGF-I resulted in a significantly increased steroidogenic response (P between < 0.05 and < 0.01). With the single exception of pregnenolone (43% ± 4.7), production of all the metabolites was amplified: 17-OH-Preg: 348% ± 88; DHA: 643% ± 127; 17-OH-P: 193% ± 36; AD: 725% ± 200; 11-deoxycortisol: 573% ± 110; cortisol: 1000%.

Our findings strongly suggest that IGF-I plays a major rôle in the regulation of steroidogenesis by promoting and maintaining enzymatic activity (17, 21- and 11β-hydroxylases) via which the function of ACTH is achieved, viz., biosynthesis of cortisol.     

Steroid biosynthesis by zona glomerulosa-fasciculata cells in primary culture of guinea-pig adrenals

Steroidogenesis was studied in guinea-pig glomerulosa-fasciculata cells maintained in primary culture for up to 7 days. The basal secretion which remained stable for the first 2 days in culture rapidly rose to reach a plateau on day 4 at levels 6-7-fold higher than those observed during the first 2 days of culture while the maximal response to ACTH in terms of cortisol and androstenedione secretion was fairly stable throughout the 7-day period. Exposure of glomerulosa-fasciculata cells to ACTH caused a stimulation of pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone, corticosterone, 11-deoxy-corticosterone, 11-deoxycortisol, cortisol, dehydroepiandrosterone, androstenedione, 11 beta-hydroxyandrostenedione and aldosterone while, after 48 h of incubation, a marked accumulation of end-products, namely cortisol and 11 beta-hydroxyandrostenedione, was observed. The half-maximal steroidogenic response to ACTH occurred at concentrations varying between 1.7 x 10(-11) and 1.1 x 10(-10) mol/l for the 12 steroids examined. Addition of 8-bromoadenosine 3', 5'-cyclic monophosphate stimulated steroid secretion in a dose-dependent manner. Maximal response to 8-bromoadenosine 3', 5'-cyclic monophosphate was obtained at 1 mmol/l, and no further rise of steroid secretion was observed after addition of ACTH. Incubation of glomerulosa-fasciculata cells with labeled corticosterone, cortisol and androstenedione indicates that only androstenedione can be converted into 11 beta-hydroxyandrostenedione, thus suggesting that this end-product is a good parameter of the C-19 steroid production by guinea-pig glomerulosa-fasciculata cells in primary culture. The present data confirm that guinea-pig glomerulosa-fasciculata cells in primary culture provide an interesting model for the study of the regulation of C-19 steroid formation by the adrenals.     

Value of 17-hydroxyprogesterone determination in exploration of adrenal cortex enzyme deficiencies]

17-hydroxyprogesterone (17-OH-P) was measured in various populations by radioimmunoassay, using a highly specific antibody produce in the rabbit. Dynamic tests were performed with ACTH, dexamethasone and estroprogestative drugs and the role played by the adrenals and the ovaries in 17-OH-P production could be assessed. 17-OH-P determination is of interest in that, it allows the diagnosis of 21-hydroxylase deficiency, where values above 10 ng/ml are often found. Associated with the measure of testosterone and delta 4-androstenedione, it is also useful in the management of the disease. In the mild form of congenital adrenal hyperplasia with late revelation of the symptoms, determination of 17-OH-P following ACTH stimulation allows of relative diagnosis.     

Low sodium intake enhances sensitivity of 11-deoxycortisol and deoxycorticosterone to ACTH in ACTH-suppressed normal subjects.

Continued administration of ACTH to patients with hypopituitarism produced normal increases in steroids dependent on microsomal cytochrome P450(21) and P450(17 alpha) but reduced responses of steroids dependent on mitochondrial cytochrome P450(11 beta-18). To explore possible mechanisms and to determine whether this dissociation occurs with short-term ACTH suppression, we have examined the steroid responses to ACTH after 1 h in 12 normal subjects after equilibration on sodium intakes of 124 mmol/d [normal sodium diet (NSD)], 22 mmol/d [low sodium diet (LSD)], and 240 mmol/d [high sodium diet (HSD)] before and during continued ACTH suppression with dexamethasone (DEX). Two distinct patterns of steroid responses were observed. Deoxycorticosterone (DOC) responses were initially reduced during LSD-DEX but eventually returned to the NSD-control (NSD-CONT) values; in contrast 18-hydroxydeoxycorticosterone and corticosterone remained suppressed. 11-Deoxycortisol and 21-deoxycortisol showed patterns similar to DOC, with a return to normal ACTH responses on LSD-DEX. Basal cortisol levels were reduced and the ACTH response was unchanged by LSD. HSD-DEX reduced basal levels of all steroids as well as their ACTH responses. LSD and/or increased activity of the renin-angiotensin system have a significant impact on 17 alpha- and 21-hydroxylation functions in the zona fasciculata to maintain a normal ACTH response of microsomally dependent steroids under these conditions. In contrast, on HSD-DEX with the renin-angiotensin system suppressed, there is generalized impairment of steroid responses to ACTH.     

Effects of synthetic ovine corticotropin-releasing factor (CRF) on plasma ACTH and cortisol in 31 normal human males

Responses of plasma ACTH and cortisol to corticotropin-releasing factor (CRF) were evaluated in 31 normal human males. 1.0 micrograms/ks of sterilized synthetic ovine CRF was administered to the subjects, aged 19 to 53 yr and weighing 50 to 78 kg, at between 9:30 a.m. and 10:30 a.m. as an intravenous bolus injection after an overnight fast. Blood specimens were drawn before and 15, 30, 60, 90 and 120 min after injection for later determination of plasma ACTH and cortisol concentrations by radioimmunoassays. Plasma ACTH and cortisol levels for all subjects rose significantly (p less than 0.001) from the basal level (mean +/- SEM, 26.8 +/- 4.5 pg/ml and 12.6 +/- 0.9 micrograms/dl) to peak levels (58.4 +/- 5.5 pg/ml and 22.9 +/- 1.0 micrograms/dl) at 30 min and at 60 min, respectively. Although the plasma concentrations of ACTH and cortisol thereafter declined gradually, the levels at 120 min (43.4 +/- 5.2 pg/ml and 18.9 +/- 0.9 micrograms/ml, respectively) were still significantly higher than the basal levels (p less than 0.001). Significant inverse correlations were observed between the basal levels of each hormone and the ratio of the peak level to the basal level (p less than 0.01), and the increases in plasma ACTH and cortisol concentrations were either not significant or much smaller for the individuals in whom the basal levels were higher than 65 pg/ml and 17.0 micrograms/dl, respectively. No serious subjective symptom was observed during the experimental period in any of the subjects.(ABSTRACT TRUNCATED AT 250 WORDS)     

Adrenal glands of mouse and rat do not synthesize androgens.

Human adrenal glands produce considerable amounts of the C-19 steroids dehydroepiandrosterone (DHEA) and androstenedione. To investigate the capability of rodent adrenals to produce these steroids, cell suspensions of mouse and rat adrenal glands were incubated in the absence and presence of adrenocorticotropic hormone (ACTH). Corticosterone levels in the incubation medium increased dramatically in the presence of ACTH, but no significant amounts of 17-hydroxyprogesterone or androstenedione could be detected. This indicates that the adrenals of rat and mouse lack the enzyme 17 alpha-hydroxylase. Absence of plasma cortisol in the presence of high levels of corticosterone confirmed these data. Plasma levels of androstenedione were significantly decreased in castrated male rats as compared to levels observed in intact males, showing the contribution of the testes to the plasma content of androstenedione. Very low levels of androstenedione were observed in female, male and castrated male mice. Plasma concentrations of DHEA were not detectable in intact and castrated male mice and rats. It is concluded that rat and mouse lack the enzyme necessary to synthesize adrenal C-19 steroids and that the adrenals in these animals, therefore, do not contribute to plasma levels of androstenedione and DHEA.     

Steroid hormones in the adrenal venous effluents in idiopathic hirsutism under basal and stimulated conditions

Steroid hormone concentrations in the peripheral blood and the adrenal veins were measured in the basal state and after ACTH stimulation in 5 patients with idiopathic hirsutism. The basal concentrations of the steroids in the adrenal veins of the patients with idiopathic hirsutism were not significantly different from a control group of 5 patients catheterized for investigation of pheochromocytoma. Following ACTH stimulation, the concentrations of the steroids in the adrenal veins were also not significantly different in the hirsute and the control groups except for the concentrations of DHA and DHAS which were higher in the patients with idiopathic hirsutism. 17-hydroxyprogesterone (17-OHP) concentrations after ACTH stimulation were lower in the hirsute group compared to the control population. It is concluded that patients with idiopathic hirsutism have a defect in the biosynthesis of cortisol proximal to the action of the 11 beta- and 21-hydroxylase enzymes, deficiencies of which have been previously considered to be the usual causes of hirsutism due to an adrenocortical abnormality. The lower 17-OHP concentrations in the hirsute group can be explained on the basis of deficiency of substrate for the action of the 17-hydroxylating enzyme, consequent to the postulated deficiency of 3 beta-hydroxysteroid dehydrogenase.     

Inhibition of cortisol production in isolated guinea-pig adrenal cells

Cortisol, added to 1 ml incubation medium containing 3-4 X 10(5) isolated guinea-pig adrenal cells, provoked a decrease in basal and ACTH (250 pg)-stimulated cortisol production, in correlation with the amounts used (50 ng-2,000 ng). A decrease in aldosterone production could be seen when cortisol concentrations reached or exceeded 1,000 ng/ml. There were no variations in either androgens (delta 4-androstenedione, dehydropiandrosterone) or 17-hydroxyprogesterone. Only 11-deoxycortisol was slightly increased. Using increasing concentrations of ACTH (50-250 pg), both in the absence and in the presence of 1,000 ng cortisol, it was noted that the inhibition induced by cortisol was of a competitive type and could be overcome by ACTH. This decrease in cortisol was concomitant with an increase in 11-deoxycortisol. Neither corticosterone nor dexamethasone reduced cortisol production. In addition, it was shown that the conversion of tritiated 11-deoxycortisol to radioactive cortisol increased significantly under the influence of 250 pg ACTH (mean relative variation of 21.7% +/- 7.7 (SEM), n = 6, P less than 0.05); but decreased significantly under the combined effect of 1,000 ng exogenous cortisol and the same dose of ACTH: (mean relative variation of 4.3% +/- 1 (SEM), n = 8, P less than 0.005). There is therefore reason to believe that the concentrations of cortisol at the adrenal level modulate the stimulation induced by ACTH and that this self-adjustment forms part of the control mechanisms involved in corticosteroidogenesis.     

Adequacy of saliva 17-hydroxyprogesterone determination using various collection methods

Steroids determination in saliva offers several advantages. The collection of saliva is a noninvasive, less stressful technique than blood withdrawal and reflects the circulating unbound fractions. The suitability of saliva for 17-hydroxyprogesterone and cortisol determinations has been documented in healthy subjects as well as in diseases like Congenital Adrenal Hyperplasia and Cushing syndrome. The aim of the study was to compare the influence of different collection methods on the results of 17-hydroxyprogesterone measurement in saliva collected by different ways, using commercially available RIAs developed for plasma. 17-hydroxyprogesterone was determined in 64 healthy adult volunteers (30 males, 34 females) in serum (Group SE) and in saliva collected before meals at 8-10 p.m. by directly spitting into a plastic tube (Group SP), using a cotton swab (Group SA) and using a polyester swab Salivette (Group SB). We used a commercially available direct radioimmunoassay without separation technique. The 17-hydroxyprogesterone mean values (ng/ml) were 1.16+/-1.3 (Group SE), 0.056+/-0.046 (Group SP), 0.089+/-0.048 (Group SA) and 0.058+/-0.049 (Group SB). The detection limit was 0.010 ng/ml. The correlations between the values in serum (Group SE) and in saliva were: r=0.77, p<0.05 (Group SP); r=0.62, p<0.05 (Group SA); r=0.70, p<0.05 (Group SB). The saliva values corresponding to the serum cut-off point of 3 ng/ml upper limit of normal values were in ng/ml 0.13 (Group SP), 0.16 (Group SA) and 0.11 (Group SB). In conclusion, 17-hydroxyprogesterone determinations in saliva using commercially available RIAs primarily developed for serum, is a reliable and easy to perform procedure. The three different methods of saliva collection showed 17-hydroxyprogesterone concentrations to have good agreement.     

Increased adrenal steroid secretion in response to CRF in women with hypothalamic amenorrhea

OBJECTIVE: To evaluate adrenal steroid hormone secretion in response to corticotropin-releasing factor (CRF) or to adrenocorticotropin hormone in women with hypothalamic amenorrhea. DESIGN: Controlled clinical study. SETTING: Department of Reproductive Medicine and Child Development, Section of Gynecology and Obstetrics, University of Pisa, Italy. PATIENT(S): Fifteen women with hypothalamic amenorrhea were enrolled in the study. Eight normal cycling women were used as control group. INTERVENTION(S): Blood samples were collected before and after an injection of ovine CRF (0.1 microg/kg iv bolus) or after synthetic ACTH (0.25 mg iv). MAIN OUTCOME MEASURE(S): Plasma levels of ACTH, 17-hydroxypregnenolone (17OHPe), progesterone (P), dehydroepiandrosterone (DHEA), 17-hydroxyprogesterone (17OHP), cortisol (F), 11-deoxycortisol (S) and androstenedione (A). RESULT(S): Basal plasma concentrations of ACTH, cortisol, 11-deoxycortisol, DHEA and 17OHPe were significantly higher in patients than in controls, whereas plasma levels of progesterone and 17-OHP were significantly lower in patients than in controls. In amenorrheic women the ratio of 17-OHPe/DHEA, of 17-OHPe/17-OHP and of 11-deoxycortisol/cortisol were significantly higher than in controls, while a significant reduction in the ratio of 17-OHP/androstenedione, of 17-OHP/11-deoxycortisol was obtained. In response to corticotropin-releasing factor test, plasma levels of ACTH, cortisol, 17-OHP, 11-deoxycortisol, DHEA and androstenedione were significantly lower in patients than in controls. In response to adrenocorticotropin hormone, plasma levels of 17-OHP, androstenedione and androstenedione/cortisol were significantly higher in patients than in controls. CONCLUSIONS: Patients suffering for hypothalamic amenorrhea showed an increased activation of hypothalamus-pituitary-adrenal (HPA) axis, as shown by the higher basal levels and by augmented adrenal hormone response to corticotropin-releasing factor administration. These data suggest a possible derangement of adrenal androgen enzymatic pathway.     

Exposure to ovarian steroids elicits a female pattern of plasma cortisol levels in castrated male macaques.

Our recent observations (1) that there is a difference in circadian patterns of plasma cortisol levels between male and female macaques and (2) that after gonadectomy these differences in the patterns and in the levels of cortisol were reduced prompted us to investigate how 17 beta-estradiol (E2) and progesterone affect cortisol secretion in orchidectomized male rhesus macaques. Five male macaques, castrated as adults, were implanted subcutaneously with segments of silastic tubing filled with E2 and with progesterone in a manner such that the levels and the sequence of these hormones mimicked those that occur during the menstrual cycle of intact female macaques. Since previous studies had shown that the difference in cortisol patterns was due to higher levels in females during the day, these studies were conducted from 0800 to 2000 hours. Blood samples were collected in an adjacent room at 15-minute intervals. Separate trials were conducted 2 weeks after E2 was implanted and levels were 110 +/- 14 pg/ml and again 2 weeks later after progesterone was implanted and E2 levels were 59 +/- 15 pg/ml; progesterone levels averaged 4.0 +/- 0.65 ng/ml. Mean plasma concentrations of cortisol (microgram/100 ml) for the 12-hour period were three-fold higher in orchidectomized males treated with E2 (17.2) and with E2 + progesterone (18.0) than in intact males (4.9). Levels in males treated with ovarian steroids were double that (8.5 micrograms/100 ml) observed for intact females.(ABSTRACT TRUNCATED AT 250 WORDS)     

Atrial natriuretic factor inhibits the CRH-stimulated secretion of ACTH and cortisol in man.

Corticotrophic secretion of ACTH is stimulated by corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP), and suppressed by glucocorticoids. In vitro and preclinical studies suggest that atrial natriuretic factor (ANF) may be a peptidergic inhibitor of pituitary-adrenocortical activity. The aim of this study was to elucidate a possible role of ANF as a modulator of ACTH release in humans. A bolus injection of 100 micrograms human CRH (hCRH) during a 30 min intravenous infusion of 5 micrograms/min human alpha atrial natriuretic factor (h alpha ANF) was administered at 19:00 to six healthy male volunteers. In comparison to saline, a blunted CRH-stimulated secretion of ACTH (mean maximum plasma level +/- SD 45 min after hCRH: saline 46.2 +/- 14.2 pg/ml, h alpha ANF 34.6 +/- 13.8 pg/ml, p-value = 0.007) and a delayed rise (10 min) in cortisol were detected. The maximum plasma cortisol levels remained nearly unchanged between saline and h alpha ANF administration (mean maximum plasma level +/- SD 60 min after hCRH: saline 182 +/- 26 ng/ml, h alpha ANF 166 +/- 54 ng/ml). No effects of h alpha ANF on basal cortisol levels were observed; in contrast, basal ACTH plasma levels were slightly reduced. Basal blood pressure and heart rate remained unaffected. In the control experiment, infusion of 3 IU AVP in the same experimental paradigm increased basal and stimulated ACTH and cortisol levels significantly in comparison to saline. These observations suggest that intravenously administered haANF inhibits the CRH-stimulated release of ACTH in man.     

Stimulation of the pituitary adrenocortical system in man by cerulein, a cholecystokinin-8-like peptide

The responses of plasma adrenocorticotropin hormone (ACTH) and cortisol to intravenous injection of cerulein (ceruletide), a decapeptide closely related to cholecystokinin octapeptide, were investigated in healthy men. In response to 16 ng/kg cerulein, plasma ACTH rose from a preinjection level of 42 +/- 11 pg/ml (mean +/- SEM) to a peak level of 81 +/- 16 pg/ml after 15 min. This ACTH increase was followed by a rise in plasma cortisol from a preinjection value of 10.3 +/- 0.9 microgram/dl to a peak value of 17.7 +/- 1.7 microgram/dl after 30 min. This is the first report of the potent stimulating effect of a cholecystokinin-8-related peptide on the pituitary-adrenal system in man.     

Serum 17-hydroxypregnenolone and 17-hydroxypregnenolone sulfate concentrations in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Serum concentrations of 17-hydroxypregnenolone, 17-hydroxypregnenolone sulfate and 17-hydroxyprogesterone were measured simultaneously in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency, using a combined radioimmunoassay method. All these precursor steroids were found to be markedly elevated in the sera of untreated patients with a salt-losing form of the disease, whereas, in untreated patients with a simple virilizing form, only the concentration of unconjugated steroids was increased and the 17-hydroxypregnenolone sulfate concentration remained within the normal range. Among the patients with a salt-losing form under maintenance therapy, these steroids were all still significantly increased in those on insufficient control, whereas only 17-hydroxyprogesterone was significantly but slightly increased in those on adequate control. Although the mechanism whereby the serum 17-hydroxypregnenolone sulfate concentration is not increased in the untreated simple virilizers is unknown, both a milder degree of 21-hydroxylase deficiency and a role of 17-hydroxypregnenolone sulfate in adrenal steroid production as a kind of supplier are suggested as possible explanations, especially in the neonatal period and early infancy. Thus, this study showed the serum concentrations of 17-hydroxypregnenolone and its sulfate together with 17-hydroxyprogesterone in patients with 21-hydroxylase deficiency in various conditions.