Profiling steroid hormones and urinary steroids

Molecular basis of human salt sensitivity: the role of the 11beta-hydroxysteroid dehydrogenase type 2

Salt-sensitive subjects (SS) increase their blood pressure with increasing salt intake. Because steroid hormones modulate renal sodium retention, we hypothesize that the activity of the 11beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) enzyme is impaired in SS subjects as compared with salt-resistant (SR) subjects. The 11betaHSD2 enzyme inactivates 11-hydroxy steroids in the kidney, thus protecting the nonselective mineralocorticoid receptor from occupation by glucocorticoids. We performed an association study using a recently identified single AluI polymorphism in exon 3 and a polymorphic microsatellite marker of the HSD11B2 gene in 149 normotensive white males (37 SS and 112 SR). The activity of the enzyme 11betaHSD2 was assessed by determining the urinary ratio of cortisol (THF+5alphaTHF) to cortisone (THE) metabolites by gas chromatography in all the 37 SS subjects and in 37 age- and body habitus-matched SR volunteers. Mean (THF+5alphaTHF)/THE ratio was markedly elevated in SS subjects compared with SR subjects (1.51 +/- 0.34 vs. 1.08 +/- 0.26, P < 0.00001), indicating enhanced access of glucocorticoids to the mineralocorticoid receptor in SS subjects. In 58% of SS subjects this ratio was higher than the maximum levels in SR subjects. The salt-induced elevation in arterial pressure increased with increasing (THF+5alphaTHF)/THE ratio (r2 = 0.51, P < 0.0001). A total of 12 alleles of the polymorphic microsatellite marker were detected. Homozygosity for the allele A7 was higher in SS subjects than in SR subjects (41 vs. 28%, P < 0.005), whereas the occurrence of the allele A7 with allele A8 was lower in SS subjects than in SR subjects (8 vs. 15%, P < 0.03). The prevalence of salt sensitivity was 35% in subjects with allele A7/A7, whereas salt sensitivity was present in only 9% of the subjects with allele A7/A8. The (THF+5alphaTHF)/THE ratio was higher in subjects homozygous for the A7 microsatellite allele as compared with the corresponding control subjects. The prevalence of the AluI allele was 8.0% in SR subjects and 5.4% in SS subjects and did not correlate with blood pressure. The decreased activity of the 11betaHSD2 in SS subjects indicates that this enzyme is involved in salt-sensitive blood pressure response in humans. The association of a polymorphic microsatellite marker of the gene with a reduced 11betaHSD2 activity suggests that variants of the HSD 11B2 gene contribute to enhanced blood pressure response to salt in humans.

Inhibition of 11beta-hydroxysteroid dehydrogenase by bile acids in rats with cirrhosis

Renal sodium retention and potassium loss occur early, in many instances in the preascitic state of cirrhosis, an observation that cannot be fully explained by increased aldosterone concentrations. We therefore hypothesize that 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2), which protects mineralocorticoid receptors (MR) from glucocorticosteroids, is down-regulated in cirrhosis. Cirrhosis was induced by bile duct ligation in rats. The urinary ratio of (tetrahydrocorticosterone + 5alpha-tetrahydrocorticosterone)/ 11-dehydro-tetrahydrocorticosterone [(THB+5alpha-THB)/THA] was measured by gas chromatography. Cortical collecting tubules (CCT) were isolated by microdissection and used for measurements of the activity of 11beta-HSD2 by assessing the conversion of corticosterone to dehydrocorticosterone. The mRNA content of 11beta-HSD2 was determined by reverse-transcription polymerase chain reaction (RT-PCR) in CCTs. The urinary ratio of (THB+5alpha-THB)/THA increased concomitantly with the urinary excretion of bile acids following bile duct ligation. Chenodeoxycholic acid (CDCA) dose-dependently inhibited 11beta-HSD2 in CCT with a Ki of 19.9 micromol/L. Four weeks after bile duct ligation, 11beta-HSD2 activity was decreased in CCT, an observation preceded by a reduced mRNA content at weeks 2 and 3. In cirrhosis, the MR-protecting effect by 11beta-HSD2 is diminished, and therefore, endogenous glucocorticoids can induce MR-mediated sodium retention and potassium loss.

Cortisol effects on body mass, blood pressure, and cholesterol in the general population

The effects of excess cortisol secretion on blood pressure and fat deposition are well documented, but the importance of this glucocorticoid in controlling these processes in normal individuals is less clear. We studied the relationship between cortisol excretion rate (tetrahydrocortisol [THF]+allo-THF+tetrahydrocortisone [THE]) and a range of important cardiovascular risk factors in 439 normal subjects (238 male) sampled from the North of Glasgow (Scotland) population. There were marked gender differences: female subjects were lighter and had lower blood pressures and cortisol levels, whereas HDL cholesterol was higher. The pattern of cortisol metabolism was also different; the index of 11beta-hydroxysteroid dehydrogenase activity (THF+allo-THF/THE) was lower and that of 5alpha-reductase (allo-THF/THF) was higher. There was a strong correlation of blood pressure (positive), cholesterol (positive), and HDL cholesterol (negative in women, positive in men) with age. Cortisol excretion rate did not correlate with blood pressure but correlated strongly with parameters of body habitus (body mass index and waist and hip measurements [positive]) and HDL cholesterol (negative). With multiple regression analysis, there remained a significant association of cortisol excretion rate with HDL cholesterol in men and women and with body mass index in men. These results suggest that glucocorticoids regulate key components of cardiovascular risk.

Clinical applications of gas chromatography and gas chromatography-mass spectrometry of steroids

This review article underlines the importance of gas chromatography-mass spectrometry (GC-MS) for determination of steroids in man. The use of steroids labelled with stable isotopes as internal standard and subsequent analysis by GC-MS yields up to now the only reliable measurement of steroids in serum. Isotope dilution GC-MS is the reference method for evaluation of routine analysis of serum steroid hormones. GC-MS is an important tool for detection of steroid hormone doping and combined with a combustion furnace and an isotope ratio mass spectrometer the misuse of testosterone by athletes can be discovered. Finally the so called urinary steroid profile by GC and GC-MS is the method of choice for detection of steroid metabolites in health and disease.

Reversed-phase high-performance liquid chromatographic screening method for serum steroids using retention index and diode-array detection

A multisteroid screening method has been developed based on the use of 1-[4-(2,3-dihydroxypropoxy)phenyl]-1-alkanones as retention index standards and UV absorbance spectra recorded on-line with a diode-array detector using reversed-phase high-performance liquid chromatographic gradient elution with acetonitrile and water. The effect of chromatographic conditions on retention indices of steroids were studied. The method was tentatively applied to profiling of steroids in serum samples.

Altered profile of endogenous steroids in the urine of patients with prolactinoma

OBJECTIVE

The aim of this study was to investigate the possible effect of prolactin on the metabolism of androgens and estrogens in patients with prolactinoma. To accomplish this, prolactin, urinary androgen, and estrogen metabolite levels were determined. In order to indirectly evaluate the possible involvement of enzymes, the concentration ratios of precursor metabolite to product metabolite were also compared with controls.

METHODS

Urine samples were obtained from 27 female patients with prolactinoma (macro, micro, and idiopathic) and from 31 age-matched normal female subjects. Urinary metabolites of 21 androgens and corticoids and 20 estrogens were analyzed by a gas chromatography-mass spectrometry system.

RESULTS

In patients with prolactinoma, urinary 17-ketosteroids, and all estrogen metabolite concentrations were elevated. The ratios of delta 5/delta 4-steroids and 5 beta/5 alpha-hydrogensteroids were higher in the patients with prolactinoma than in normal female controls. In addition, no significant differences between patients and controls were observed in the precursor metabolite to product metabolite ratios relating to estrogen metabolism.

CONCLUSION

Our data suggests that enhanced PRL levels have a direct effect on urinary steroid secretion and metabolism, probably due to lowered activities of 5 alpha-reductase and 3 beta-hydroxysteroid dehydrogenase in the patients with prolactinoma.

Derivatization procedures for gas chromatographic-mass spectrometric determination of xenobiotics in biological samples, with special attention to drugs of abuse and doping agents

The development of low cost MS detectors in recent years has promoted an important increase in the applicability of GC-MS system to analyze for the presence of foreign substances in the human body. Drugs and toxic agents are in vivo metabolized in such a way that more polar compounds are usually formed. Derivatization of these metabolites is often an unavoidable requirement for gas chromatographic analysis. Application of derivatization methods in recent years has been relevant, especially for silylation, acylation, alkylation and the formation of cyclic or diastereomeric derivatives. Given the relevance of drug of abuse testing in modern toxicology, main derivatization procedures for opiates, cocaine, cannabis, amphetamines, benzodiazepines and LSD have been reviewed. Papers describing the analyses of drugs of abuse in matrixes other than blood, such as hair or sweat, have received special attention. Advances in derivatization for sports drug testing have been particularly relevant for anabolic steroids, diuretics and corticosteroids. Among the several methodologies applied, the formation of trimethylsilyl, perfluoroacyl or methylated derivatives have proved to be both versatile and extensively used. Further advances in derivatization for GC-MS applications in clinical and forensic toxicology will depend on the one hand on the degree of further use of GC-MS for routine applications and, on the other hand, on the alternative progress made for developments in LC-MS or CE-MS. Last but not least, the appearance of comprehensive libraries in which reference spectra for different derivatives of many drugs and their metabolites are collected will have an important impact on the expansion of derivatization in GC-MS for toxicological applications.

Seasonal changes in the production of two novel and abundant ovarian steroids in the channel catfish (Ictalurus punctatus)

Timely and appropriate changes in steroid plasma titers are necessary for successful reproduction in all vertebrates. Gonadal steroidogenesis of the most intensively cultured teleost species in North America, the channel catfish (Ictalurus punctatus), is poorly understood so a year-long study was conducted to investigate seasonal changes in ovarian steroidogenesis. Incubations of ovarian tissue were conducted monthly with [3H]pregnenolone and the medium was analyzed by high-performance liquid chromatography (HPLC) with radioactivity detection. The suite of steroids produced by the catfish ovary included the expected sex steroids (estradiol and testosterone) and 18 additional ovarian metabolites, including five steroids that have yet to be identified. Androstenedione, 20beta-dihydroprogesterone, 5|P-dihydrotestosterone, estriol, 11beta-hydroxyandrostenedione, 17-hydroxypregnenolone, 17-hydroxyprogesterone, 11beta-hydroxytestosterone, and progesterone were characterized by a combination of HPLC and thin-layer chromatography. Two of the most abundant steroids were isolated and analyzed by gas chromatography coupled with mass spectrometry (GC-MS). One of the steroids, 7alpha-hydroxypregnenolone (7P5), is a novel steroid in teleosts and was produced late in vitellogenic growth of the oocyte. Evidence suggests that the enzyme responsible for converting pregnenolone to 7P5, 7alpha-hydroxylase, is a cytochrome P450. The second abundant steroid metabolite was partially characterized by GC-MS as an hydroxylated form of 17-hydroxy-pregnenolone (chi,17P5). This steroid was most abundant when the ovary was regressed and during early vitellogenesis and rapidly decreased prior to spawning. In mammals, 7P5 has been identified as an important neurosteroid; however, the reproductive significance of 7P5 and chi,17P5 in catfish is unknown.

Prominent sex steroid metabolism in human lymphocytes

Steroid metabolism was investigated in cultured human B-lymphoblastoid cells (B-LCL), and peripheral blood T and B cells. Gene expression was examined by reverse-transcription polymerase chain reaction amplification (RT-PCR). Appropriate sized transcripts were detected in both cultured and fresh peripheral lymphocytes for CYP11A, CYP17, HSD11L (11beta-hydroxysteroid dehydrogenase I), HSD17B1 (17beta-hydroxysteroid dehydrogenase type I) and SRD5A1 (5alpha-reductase I). B-LCL, but not T and B cells, expressed CYP11B. There was minimal expression of HSD3B1 and HSD3B2 (3beta-hydroxysteroid dehydrogenase I and II) in B-LCL and T cells. Transcripts for CYP19 and HSD11K were not detected. Corresponding enzymatic activity was detectable only for 17-hydroxysteroid dehydrogenase and 5alpha-reductase, respectively producing testosterone and 5alpha-dihydrotestosterone. Steroid identities were confirmed by gas chromatography/mass spectrometry (GC/MS). One metabolite thought to be deoxycorticosterone was identified by GC/MS as 6alpha-hydroxypregnanolone. It was concluded that sex hormone metabolism, including androgen synthesis, occurs in lymphocytes, and may modulate immune response.

Emulsion formulations of testosterone for nasal administration

The nasal route has received a great deal of attention due to the many advantages of nasal delivery over parenteral administration. The male sex hormone testosterone is ineffective when administered orally due to its gut wall and first-pass metabolism. Therefore, an alternative method for delivery would be the intranasal route, if the lack of aqueous solubility can be overcome. In this study a new approach to emulsion formulations of the drug has been proposed based on the hypothesis that increased absorption is possible upon solubilization of the drug and/or prolongation of the formulation residence time in the nose. Three differently charged testosterone submicron size emulsion formulations with various zeta potentials (+24.8, -23.0 and 0.06 mV) were prepared as nasal spray formulations. A dose of approximately 3.8 mg testosterone per rabbit was administered to four rabbits and the bioavailability of the emulsion formulations was assessed and compared with an i.v. formulation via solid-phase extraction, followed by an HPLC analysis method. Statistical analysis of the normalized data indicated a bioavailability of 55, 51 and 37% for positively, negatively and neutrally charged emulsions respectively. The results of this study strongly suggest that emulsion formulations have some potential to be considered for nasal delivery. Further, both the positively and negatively charged emulsion formulations provided a better bioavailability than the neutral charged emulsion, probably indicating that the charged particle interactions between emulsion globules and the mucus layer prolong the contact of drug with nasal membrane thus enhancing drug absorption.

Convenient chromatographic prepurification step before measurement of urinary cortisol by radioimmunoassay

We applied various prepurification protocols (extraction with different solvents, liquid/solid separation on bonded silica media, Celite, and Sephadex LH20 chromatography) with a range of commercially available RIA kits to measure cortisol in urine samples. We then compared the results with the concentrations measured by a HPLC method validated with reference to isotope dilution gas chromatography–mass spectrometry. We conclude that chromatography on a commercial, prepacked diol minicolumn (Waters™ Sep-Pak Vac RC) in combination with dichloromethane extraction is a convenient and very effective purification step before RIA of urinary cortisol in patients not receiving corticoid medication. We tested numerous steroids for interference and found that free polar cortisol derivatives (hydroxylated or hydrogenated) could only partially account for the overestimations routinely encountered when free urinary cortisol concentrations are measured by direct RIA.

Direct determination of anabolic steroid conjugates in human urine by combined high-performance liquid chromatography and tandem mass spectrometry

A novel screening procedure for the sulfate and glucuronide conjugates of testosterone (T) and epitestosterone (E) in human urine was developed based on liquid-solid extraction and microbore high-performance liquid chromatography combined on-line with ion-spray tandem mass spectrometry. Confirmation of the sulfate and glucuronide conjugates of testosterone and epitestosterone isolated from normal human urine was achieved by selected reaction monitoring of characteristic product ions of the parent compounds. Endogenous levels of the steroid conjugates are detected in normal male urine and an increase is observed when the sample is fortified with authentic analytical standards of the conjugates. Calibration curves of all steroid conjugates in urine are linear over a range of twenty. Deuterated internal standards of testosterone glucuronide and epitestosterone sulfate were used for quantitation of the endogenous conjugates. T/E ratios were determined based on the glucuronide fractions of six replicates from a normal male and were shown to be statistically reproducible and below the accepted T/E threshold of 6:1. Sulfate conjugates were shown to be present at significantly lower levels in the urine. The method has potential as an alternative for monitoring anabolic steroid conjugates in human urine.

Direct measurement of steroid sulfate and glucuronide conjugates with high-performance liquid chromatography-mass spectrometry

Direct detection of several steroid glucuronide and sulfate conjugates was achieved with electrospray reversed-phase HPLC-mass spectrometry. Separation of steroid 17-OH or 5-H epimers conjugated with glucuronide or sulfate could be achieved using gradient elution. Testosterone glucuronide, testosterone sulfate, epitestosterone sulfate and epitestosterone glucuronide were chromatographically resolved, although significant variation in solvent strength was observed between methanol and acetonitrile. Positive ionization mode MS and MS-MS spectra were employed to obtain both quantitative and structural information. Some differences were noted with respect to steroid structure and adduct formation, including significant differences in the stability of epimers in the declustering region of the interface. Negative ionization mode, although having lower limits of detection, did not provide useful structural information in either the MS or MS-MS mode. Using a packed capillary column (300 microns I.D.), a detection limit of 25 pg was achieved for epitestosterone glucuronide.

A comparison of nebulized budesonide with oral prednisolone in the treatment of exacerbations of obstructive pulmonary disease

Nebulized corticosteroids in acute bronchospasm may offer topical anti-inflammatory activity while minimizing undesirable systemic effects. We compared the side-effect profile of nebulized budesonide (2 mg twice daily) with that of oral prednisolone (30 mg once daily) in a randomized parallel-group study of 19 adults with severe acute airway obstruction. Over the 5 days of the study, baseline forced expiratory volume in 1 second (FEV1) increased from 1.8 (95% confidence interval [CI], 0.7) to 2.1 (95% CI, 0.7) L in the group that received oral corticosteroids compared with 1.9 (95% CI, 0.7) to 2.0 (95% CI, 0.7) L in the group that received nebulized corticosteroid. All biochemical variables were similar at day 1. Comparison of budesonide treatment with prednisolone on day 5 showed that urinary corticosteroid metabolites were significantly higher (2012 [95% CI, 812] compared with 1079 [95% CI, 346] mg/24 hr [p < 0.05]), urinary androgen metabolites were not different, serum osteocalcin was elevated (2.3 [95% CI, 1.4] compared with 0.6 [95% CI, 0.6] ng/ml [p < 0.05]), and 24-hour urinary calcium to creatinine ratios were lower (0.28 [95% CI, 0.1] compared with 0.53 [95% CI, 0.2]), whereas urinary hydroxyproline to creatinine ratios were similar. The biochemical markers associated with corticosteroid side effects improve in patients treated with nebulized corticosteroids compared with patients who receive conventional treatment.

Pyrene sulphonyl chloride as a reagent for quantitation of oestrogens in human serum using HPLC with conventional and laser-induced fluorescence detection

A highly sensitive HPLC method with conventional and laser-induced fluorescence detection for the analyses of oestrogens is described. beta-oestradiol (beta-ES) was chosen as a model and derivatized with pyrenesulphonyl chloride (PSCL), a novel derivatizing reagent, using a two-phase system with tetrapentylammonium bromide (TPABR) as a phase transfer catalyst. Derivatization was complete in 30 s at room temperature and concentrations as low as 5 x 10(-10) M could be derivatized and detected. The concentration detection limit PSCL derivatized beta-ES was 2 x 10(-11) M which corresponds to an on-column detection limit of one femtomole using conventional chromatography and detection. The relative standard deviation (n = 6) of the derivatization carried out at 2.5 x 10(-9) M was 4%. No significant loss of peak-height of the derivative was observed at room temperature over 24 h period. Baseline resolution of PSCL derivatized oestrone, equilin and beta-oestradiol was achieved with ACN:H2O (75:25 v/v) using a Bondclone C-18 column. The method described here is sufficiently sensitive for analyses of beta-oestradiol at low pg/mL concentrations in 1 mL of human serum. The PSCL derivatives of oestrogens demonstrate excellent potential for excitation by laser-induced fluorescence using the 351 nm line of an Ar ion laser or the 325 nm line of He-Cd laser. A concentration limit of detection of 4 x 10(-12) M for beta-oestradiol was achieved using the 325 nm line of an He-Cd laser. This corresponds to 0.2 fmol of derivatized beta-oestradiol on-column.

Proposed definitive methods for measurement of plasma testosterone and 17 alpha-hydroxyprogesterone

OBJECTIVES

This report provides the results of the development and evaluation of definitive isotope dilution/mass spectrometry (ID/MS) methods for the determination of testosterone and 17 alpha-hydroxyprogesterone in human plasma at concentrations ranging from 1.4 to 37.9 nmol/L and 1.5 to 45.4 nmol/L, respectively. The internal standards were 16, 16, 17-2H-testosterone and 21,21,21, -2H-17 alpha-hydroxyprogesterone. The development of optimum extraction and derivatization procedures, and studies of storage time, temperature effects, accuracy, and precision are presented.

RESULTS

The results indicate that the methods employing the TBDMS derivative of testosterone and MO-TMS derivative of 17 alpha-hydroxyprogesterone are capable of generating accurate and precise data at the inherently low concentrations given, with recovery greater than 95%. Accuracy of testosterone in the fortified steroid-free and pooled plasma by ID/MS measurement was good because the relative error ranged from +3.1% to -0.7, with a mean of 0.9% over the concentration levels of 1.4 to 37.9 nmol/L testosterone, and the imprecision ranged from 4.2% to 0.7% CV, with a mean of 1.9%. Accuracy of 17 alpha-hydroxyprogesterone in the fortified steroid-free and pooled plasma was also good, considering the inherently low concentrations. The relative error ranged from -2.1% to +1.5%, with a mean of 1.1%, and the imprecision ranged from 3.8% to 0.8% CV with a mean of 1.3% over concentration levels of 1.5 to 15.1 nmol/L. The high precision and accuracy and absence of statistically significant bias qualifies these methods as candidate definitive methods for plasma testosterone and 17 alpha-hydroxyprogesterone.

Sodium status, corticosteroid metabolism and blood pressure in normal human subjects and in a patient with abnormal salt appetite

1. A patient with severe hypertension was found to have mildly impaired 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) activity on the basis of urinary steroid metabolite ratios, low plasma aldosterone, angiotensin II and renin levels and marginally low levels of plasma potassium. 2. The patient also had a compulsively high salt intake. 3. We tested the hypothesis that high salt intake may affect 11 beta-HSD activity. 4. High salt intake in normal subjects did not significantly alter either blood pressure or 11 beta-HSD activity. 5. We suggest that the potentially small hypertensive effect of the partial enzyme deficiency in our patient, also reported in patients with essential hypertension, has been markedly amplified by the very high salt intake.

Facile synthesis of [16,16,17-2H3]-testosterone, -epitestosterone and their glucuronides and sulfates

The analysis of trace components in complex biological matrices requires the use of reliable internal standards. For the gas chromatography/mass spectrometry (GC/MS) and high performance liquid chromatography/mass spectrometry (HPLC/MS) analyses, the stable isotope-labelled analogues of the analyte molecules are the most appropriate internal standards. In this work high-yield synthetic procedures for stably labelled and isotopically pure [16,16,17-2H3]-testosterone and- epitestosterone are reported. Synthetic methodologies for the glucuronidation and sulfation were established with the commercially available epitestosterone. Structure characterization of 4-androsten-17 alpha-ol-3-one methyl-2',3',4'-tri-O-acetyl-beta-D-glucuronate was made by two-dimensional nuclear magnetic resonance (COSY). Subsequently glucuronidation of [16,16,17-2H3]-testosterone and sulfation of [16,16,17-2H3]-epitestosterone were carried out at greater than 60% yield. However, the yield from the glucuronidation of epitestosterone was not as high. Electrospray mass spectrometry of four conjugates: testosterone sulfate, epitestosterone sulfate, testosterone glucuronide and epitestosterone glucuronide was carried out in the positive ion mode at a number of orifice voltages (50-95 V). Studies of the collisionally induced dissociation at both the interface and in the collision cell (MSMS) confirmed that the glycosidic bond of epitestosterone glucuronide was more labile than that of testosterone glucuronide. Use of the deuterated internal standards is reported to demonstrate the direct analysis of the steroid conjugates by HPLC/MS.

Extra-adrenal effects of metyrapone include inhibition of the 11-oxoreductase activity of 11 beta-hydroxysteroid dehydrogenase: a model for 11-HSD I deficiency

BACKGROUND AND OBJECTIVE

Previous studies suggesting effects of metyrapone on extra-adrenal corticosteroid metabolism have involved significant alterations in plasma cortisol. We have therefore studied effects of metyrapone on urinary excretion of steroids in a group of patients treated concurrently with hydrocortisone so that changes in plasma cortisol were minimized.

DESIGN

Replacement doses of hydrocortisone (30 mg/day) were given concurrently with metyrapone (2-4 g/day) for 2 weeks. Blood samples were taken and 24-hour urinary steroid collections were made at baseline and after 1 and 2 weeks of treatment.

PATIENTS

Subjects were 6 female patients with major depression from a trial of metyrapone as an antidepressant.

MEASUREMENTS

Urinary steroid profiles were measured by gas chromatography; plasma cortisol and urinary free cortisol were measured by fluorescence immunoassay.

RESULTS

Plasma cortisol levels were not significantly decreased by treatment, while excretion of 11-deoxycortisol metabolites increased eightfold after 2 weeks indicating that concurrent hydrocortisone administration had not suppressed the adrenal. Ratios reflecting 11 beta-hydroxy/11-oxo metabolites of cortisol were significantly decreased, consistent with inhibition of the 11-oxoreductase activity of 11 beta-hydroxysteroid dehydrogenase (11-HSD). Other changes included significant decreases in the rates of 5 alpha vs 5 beta and of 20 alpha vs 20 beta reduction of corticosteroids.

CONCLUSIONS

Metyrapone has multiple effects on extra-adrenal corticosteroid metabolism and is the only agent we know of which selectively inhibits 11-oxoreductase. Metyrapone thus provides a model for 11-HSD I deficiency and a tool for in-vitro studies of cortisol-cortisone interconversion. The results also suggest mechanisms whereby corticosteroid effects can be regulated separately from corticosteroid synthesis.

High-performance liquid chromatographic analysis of corticosteroids

This review presents recent developments in high-performance liquid chromatographic (HPLC) analysis of corticosteroids for the determination of clinically important steroids in biological specimens. Various sample preparation techniques are described.

Methods for urinary testosterone analysis

Urinary testosterone analysis requires a multistep procedure to achieve a good degree of sensitivity and specificity in the dosage. Hydrolysis, extraction, purification and quantification are usually performed in sequence, and several options can be chosen for each of them. After introductory remarks on the applications of urinary testosterone measurement and a short description of the metabolic pathway of the hormone, an overview of the techniques most commonly used in each step is presented. Advantages and disadvantages of each of them are outlined, and a procedure for urinary testosterone analysis is suggested. The procedure consists of: enzymatic hydrolysis with Helix pomatia juice, followed by solid-phase extraction of hydrolyzed urine by a C18 cartridge coupled with an NH2 cartridge and high-performance liquid chromatography cleanup of the extract. Then, quantification can be achieved by gas chromatography or radioimmunoassay.

A novel nonhepatic hydroxycholesterol 7 alpha-hydroxylase that is markedly stimulated by interleukin-1 beta. Characterization in the immature rat ovary

During studies on the regulation of rat ovarian steroidogenic enzymes by interleukin-1 beta (IL-1 beta), we observed substantial metabolism of 25-hydroxycholesterol to two unusual polar products. This unexpected effect was observed both in isolated granulosa cells and in whole ovarian dispersates and was also induced by tumor necrosis factor alpha, but not by insulin-like growth factor I or follicle-stimulating hormone. The effect was dependent on time and the dose of IL-1 beta and was blocked by and IL-1 receptor antagonist. The formation of the polar metabolites was inhibited by ketoconazole and trilostane, but not by aminoglutethimide. Subsequent purification of these novel metabolites and analysis by gas chromatography/ mass spectrometry, NMR, and high performance liquid chromatography revealed them to be related 7 alpha-hydroxylated hydroxycholesterols (cholest-4-ene-7 alpha,25-diol-3-one and cholest-5-ene-3 beta,7 alpha,25-triol). IL-1 beta-stimulated ovarian 7 alpha-hydroxylase activity (3-10 pmol/min/mg of cellular protein) was nearly 4-fold that of control levels using 25-hydroxycholesterol as substrate. Activities at or below control levels were observed when IL-1 beta-treated cell sonicates were boiled or assayed in the presence of NADH (rather than NADPH), indicating that involvement of a nonenzymatic process was unlikely. IL-1 beta-stimulated 7 alpha-hydroxylase activity was inhibited to basal levels by a 10-fold excess of unlabeled 25- or 27-hydroxycholesterol, but not by cholesterol, pregnenolone, progesterone, testosterone, or dehydroepiandrosterone, suggesting that ovarian 7 alpha-hydroxylase is specific for hydroxycholesterols. Furthermore, when IL-1 beta-treated ovarian cultures were incubated with radiolabeled cholesterol or testosterone, no 7 alpha-hydroxylated products were observed. We were also unable to detect any mRNA transcripts for liver cholesterol 7 alpha-hydroxylase in IL-1 beta-stimulated ovarian cultures. This study describes an ovarian hydroxycholesterol 7 alpha-hydroxylase that differs from liver cholesterol 7 alpha-hydroxylase and from other nonhepatic progestin/ androgen 7 alpha-hydroxylases. The novel finding of the regulation of a 7 alpha-hydroxylase by IL-1 beta (and tumor necrosis factor alpha) suggests a unique role for cytokines in the regulation of cholesterol metabolism in the ovary and possibly other tissues.

Chemometric evaluation of urinary steroid profiles in doping control

Ten endogenous steroid hormones and metabolites were determined according to the screening procedure for anabolic steroids in spot urine samples from 105 healthy young male athletes (control samples) and 23 males that tested positive for anabolic steroids in the doping control (positive samples). The GC-MS peak areas for each sample were normalized to total area. Multivariate data analysis by Partial Least Square Regression (PLSR) and using a coded Y-variable (positive samples: +1 and control samples -1) allows projection of the most systematic profile structures into a 2D plot revealing a clear distinction between the control and misuser groups. The most important determinants of the location in the loading plot were the ratios of testosterone to epitestosterone and androsterone to etiocholanolone. The ratio between 11-beta-hydroxyandrosterone and 11-beta-hydroxy-etiocholanolone was less important, in accordance with the fact that anabolic-androgenic steroid intake primarily affects the excretion of testosterone from the testis and to a much lesser degree adrenal steroid genesis. We present a preliminary validation of this model (PLS1-DISCRIM) for analysing steroid profiles in doping control samples from several categories of athletes, some of which are suspected for drug misuse, and results from a one dose excretion study in healthy volunteers. Our findings suggest that use of multivariate PLS-regression may give valuable information about anabolic androgenic steroid misuse in sport. When appropriately calibrated, this methodology may delineate drug misusers directly from the screening procedure for anabolic steroids in spot urine tests.

Evidence of coexisting changes in 11 beta-hydroxysteroid dehydrogenase and 5 beta-reductase activity in subjects with untreated essential hypertension

We compared corticosteroid metabolite excretion rates and patterns in a group of 68 subjects with untreated essential hypertension and a matched group of 48 normotensive control subjects. The ratio of tetrahydrocortisol plus allotetrahydrocortisol to tetrahydrocortisone and the ratio of allotetrahydrocortisol to tetrahydrocortisol were significantly higher in the hypertensive group. This is qualitatively similar to the situation found in patients with the syndrome of apparent mineralocorticoid excess or subjects treated with licorice or carbenoxolone where hypertension is known to arise from deficiencies of 11 beta-hydroxysteroid dehydrogenase and 5 beta-reductase activities. The equivalent ratios for corticosterone metabolites were not different between groups, but total corticosterone metabolite excretion was higher in the hypertensive group. Plasma cortisol levels were lower in hypertensive than in control subjects, but corticosterone levels were higher. This evidence supports a previous suggestion that the activities of these two enzymes may be reduced in essential hypertension, but the contribution of these changes to hypertension is not known.

Routine high-performance liquid chromatographic determination of urinary unconjugated cortisol using solid-phase extraction and ultraviolet detection

An HPLC method with solid-phase extraction for the specific determination of urinary free cortisol is described. A 3-ml urine sample is cleaned up on a disposable cartridge C 18. After successive washing with 0.025 mol/l borate buffer (pH 7.5) and a mixture of acetone and water, retained cortisol and 6 alpha-methylprednisolone (internal standard) are eluted with ethyl acetate. The recovery of cortisol is 92.9 +/- 4.4%. The reversed-phase chromatographic procedure uses an octadecyl-bonded column with a mobile phase composed of methanol, tetrahydrofuran and water with UV detection at 245 nm. The calibration curve is linear up to a cortisol concentration of 356 nmol/l. Coefficients of variation show good reproducibility of the assay. The detection limit is 9 nmol/l (16 pmol injected). The normal range of urinary free cortisol excretion was found to be 17-132 nmol/24 h. This simple and convenient method is suitable for routine use.

HLA haplotypes and hormonal studies in 25 Italian families of patients with classical and non-classical 21-OH deficiency

To investigate the genetic polymorphisms of the HLA region and the molecular defect of the P450c21B gene in congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, we studied 89 individuals from 25 families of CAH patients (14 classical forms, 11 non-classical forms). The following immunogenetic and hormonal investigations were performed: HLA-A and B typing, restriction fragment length polymorphism (RFLP) analysis of 21-hydroxylase A and B genes, and serum 17-OH-progesterone values determined basally and 60 min after ACTH stimulation. In the patients affected by the classical form, RFLP analysis revealed 5 deletions and 1 gene conversion in 6 haplotypes and no molecular defect in the others, who probably carry point mutations. In the patients with non-classical form we found P450c21A duplication in 11/18 haplotypes; 9 of the 11 patients shared the HLA-B14 allele. Utilizing both hormonal and genetic data we identified two cryptic forms; hormonal data alone failed to differentiate heterozygous from normal individuals.

Optimization of the high-performance liquid chromatrographic separation of a mixture of natural and synthetic corticosteroids

Systematic optimization of the HPLC separation of a mixture of natural and synthetic corticosteroids was carried out for screening purposes. The method involves binary, ternary or quaternary mixtures containing water, methanol, acetonitrile and tetrahydrofuran. It was possible to separate thirteen out of fourteen corticosteroids contained in a sample in about 26 min, with a 5-microns Hypersil-C18 (250 mm x 4.6 mm I.D.) column thermostated at 30 degrees C, using a mobile phase composed of water-tetrahydrofuran (72:28, v/v). This separation was not improved using other C8 or C18 columns. The effect of temperature on the separation of these compounds was also studied. Calibration graphs were established for each corticosteroid up to 8 micrograms/ml using indapamide as internal standard. The detection limits were in the range 0.02-0.14 ng. The optimized method was applied to urine samples spiked with corticosteroids and showed potential for future applications.

Quantification of mammalian lignans in biological fluids using gas chromatography with ion mobility detection

A method is presented to quantify selected mammalian lignans in human physiological fluids by gas chromatography (GC) coupled with ion mobility spectrometry (IMS). The use of IMS following GC permitted the selective and sensitive measurement of 2,3-bis(3-hydroxybenzyl)butane-1,4-diol (i.e., enterodiol) and trans-2,3-bis(3-hydroxybenzyl)-gamma-butyrolactone (i.e., enterolactone) concentrations in urine and plasma following dietary supplementation with whole wheat/flaxseed bread high in mammalian lignan precursors. Following six weeks of flaxseed feeding, urinary and plasma levels of enterodiol and enterolactone were elevated, exceeding the amounts found at baseline by a factor of 3-5. The approach to mammalian lignan methodology presented herein provides novel analytical phytochemical procedures for assessing the impact of lignan consumption in human health and disease.

Determination of estrogens in plasma by high-performance liquid chromatography after pre-column derivatization with 2-(4-carboxyphenyl)-5,6-dimethylbenzimidazole

A sensitive method for the determination of estrogens by high-performance liquid chromatography with fluorimetric detection was reported. The estrogens were derivatized with 2-(4-carboxyphenyl)-5,6-dimethylbenzimidazole to their esters in the presence of 4-piperidinopyridine and 1-isopropyl-3-(3-dimethylaminopropyl)carbodiimide perchlorate. The resulting esters were extracted with a Sep-Pak C18 plus cartridge, and then esters were separated on a Wakosil 5C18 column with water-methanol (10:90, v/v) as the mobile phase. The esters were detected by fluorimetric detection (excitation wavelength = 336 nm, emission wavelength = 440 nm). The within-day relative standards deviations (n = 6) for each estrogen (1.0 ng per 100 microliters of plasma) were 8.7-13.0%, and day-to-day relative standard deviations (n = 6) were 8.3-11.8%. The limits of detection for estrogens (estrone, estradiol, estriol, estetrol, ethynyl-estradiol, 2-hydroxyestradiol, 4-hydroxyestradiol) were 0.1-0.2 pg per 100 microliters of plasma (signal-to-noise ratio 3).

Steroid hormone secretion by testicular tissue from African catfish, Clarias gariepinus, in primary culture: identification and quantification by gas chromatography - mass spectrometry

With the final aim of identifying the testicular steroids involved in the feedback mechanism of the hypothalamus-pituitary-gonad axis, steroid secretion by the testis of African catfish, Clarias gariepinus, was studied in vitro, by means of gas chromatography followed by mass spectrometry. Testicular fragments of sexually mature catfish raised in captivity were incubated in L-15 medium with and without catfish pituitary extract (cfPE). Without adding cfPE, 22 steroids could be identified, amongst which 11β-hydroxyandrostenedione, 11β-hydroxytestosterone, 11-ketotestosterone and 11-ketoandrostenedione were dominating. After incubation in the presence of cfPE, the concentrations of the four 11-oxygenated steroids were increased about 4-fold. The amounts of pregnane derivatives in the incubation medium showed the largest increases in the presence of cfPE. 5β-Pregnane-triol levels, for example, were 60-fold higher than in the medium from control incubations. The secretion of 5α- and 5β-androstanes was also stimulated by cfPE.The stimulation was not equal for all steroids, indicating that cfPE not only stimulates total steroidogenesis by increasing the availability of cholesterol, but also by influencing specific steroid converting enzyme activities.

Corticosteroidogenesis in the toad Bufo arenarum H: evidence for a precursor role for an aldosterone 3 beta-hydroxy-5-ene analogue (3 beta, 11 beta, 21-trihydroxy-20-oxo-5-pregnen-18-al)

A material isolated following pregnenolone incubations with toad (Bufo arenarum) inter-renal tissue at 28 degrees C has been identified as a 3 beta-hydroxy-5-ene analogue of aldosterone (3 beta, 11 beta, 21-trihydroxy-20-oxo-5-pregnen-18-al). The initial identification was made by enzymic and m.s. methods, and structural confirmation was achieved through comparison with chemically synthesized authentic material. The relative efficacy of corticosterone, 18-hydroxycorticosterone and the 3 beta-hydroxy-5-ene aldosterone analogue as aldosterone precursors was evaluated. In the in vitro situation studied, the 3 beta-hydroxy-5-ene steroid was by far the best precursor.

The timing of placental competence in pregnancy after oocyte donation

OBJECTIVE

To test the timing of placental support of pregnancy.

DESIGN

Steroid levels in blood and urine were determined in pregnancy after ET into women with ovarian failure.

SETTING

The study was carried out in a private IVF clinic and a university endocrine department.

PATIENTS

Four patients with ovarian failure were treated by IVF using donor oocytes.

INTERVENTIONS

Estrogen and P were given, up to the point of ET, to achieve the hormonal levels in the ranges for normal menstrual cycles. Pregnancy was supported in the first trimester by exogenous steroids.

OUTCOME

The four pregnancies went to term, and each resulted in singleton livebirths.

RESULTS

Increases in plasma P concentrations and in urinary pregnanediol excretion rates were indications for a placental contribution to the hormone pool.

CONCLUSIONS

One hundred mg of P were probably a supraphysiological dose to support pregnancy 6 to 8 weeks after conception. The fetoplacental unit was competent from 10 to 12 weeks' gestation.

Urinary testosterone measurement by gas chromatography after solid-phase extraction and high-performance liquid chromatography

A method was developed for the rapid determination of testosterone in urine. The procedure consists of solid-phase extraction (SPE) followed by high-performance liquid chromatographic (HPLC) clean-up before gas chromatographic determination. Recovery was evaluated by adding [3H]testosterone (10(4) cpm) to urine samples; the mean recovery of radioactivity after SPE and HPLC was 82%. Precision was estimated by repeated measurement of testosterone in four different urine samples; the coefficient of variation was 7.9% (95% confidence limits 6.1-11.4%). Accuracy was evaluated by standard addition and dilution assays; a linear relationship was found between the expected and observed values (r2 = 0.982). The method is rapid, effective and suitable for routine analysis.

Regulation of pregnenolone synthesis in C6-2B glioma cells by 4'-chlorodiazepam

An experimental model to study synthesis of cholesterol and pregnenolone from the precursor mevalonolactone (MVA) was developed in C6-2B glioma cells. The steroidogenic capability of this cell line and the regulation of pregnenolone production by 4'-chlorodiazepam (4'CD), a specific ligand for the mitochondrial diazepam binding inhibitor (DBI) receptor (MDR), were investigated. Cells maintained in serum-free media were incubated with lovastatin (20 microM) and two inhibitors of pregnenolone metabolism, trilostane (25 microM) and 1,2,3,4-tetrahydro-4-oxo-7-chloro-2-naphthylpyridine (10 microM). Under these conditions the incorporation of [3H]MVA into cholesterol and pregnenolone formation was biphasic, with an initial rapid phase (within 1 min) followed by a slower phase. Cholesterol and pregnenolone were identified by coelution with authentic steroids from a Si 60 Lichrosorb column and gas chromatography/mass spectrometry. Pregnenolone synthesis in intact C6-2B glioma cells was stimulated by nanomolar concentrations of 4'CD after 5 min of incubation with MVA. The stimulatory effect was dependent on drug concentration and the maximal effect was achieved at 10 nM. The time course showed that the incorporation of MVA into pregnenolone is accelerated by the MDR ligand. Cholesterol synthesis is only slightly and not significantly affected by 4'CD. These results support the view that steroid synthesis occurs in a glioma cell line. Moreover, we provide evidence for a rapid steroid synthesis in C6-2B glioma cells, which in turn appears to be accelerated by 1-100 nM 4'CD, a MDR ligand.

The methyl-5 alpha-dihydrotestosterones mesterolone and drostanolone; gas chromatographic/mass spectrometric characterization of the urinary metabolites

Before including the detection of the methyl-5 alpha-dihydrotestosterones mesterolone (1 alpha-methyl-17 beta-hydroxy-5 alpha-androstan-3-one) and drostanolone (2 alpha-methyl-17 beta-hydroxy-5 alpha-androstan-3-one) in doping control procedures, their urinary metabolites were characterized by gas chromatography/mass spectrometry. Several metabolites were found after enzymatic hydrolysis and conversion of the respective metabolites to their trimethylsilyl-enol-trimethylsilyl ether derivatives. The major metabolites of mesterolone and drostanolone were identified as 1 alpha-methyl-androsterone and 2 alpha-methyl-androsterone, respectively. The parent compounds and the intermediate 3 alpha,17 beta-dihydroxysteroid metabolites were detected as well. The reduction into the corresponding 3 beta-hydroxysteroids was a minor metabolic pathway. All metabolites were found to be conjugated to glucuronic acid.

Adrenal cortex, tumor, and peripheral production of deoxycorticosterone

A method is reported for the measurement of the urine excretion rates of tetrahydro-11-deoxycorticosterone (3 alpha,5 beta-THDOC), an important metabolite of 11-deoxycorticosterone (DOC). Quantification using gas chromatography/mass spectrometry (GC/MS) was achieved by comparing the ion fragment response for the molecular ion (m/z 507) of the analyte (as methyloxime trimethylsilyl ether derivative) to that of a fixed amount of an isomer of THDOC added to urine as internal standard. To improve the specificity of measuring THDOC in clinical samples, an additional Sephadex LH-20 chromatography step was introduced to separate 11-deoxycortisol and some progesterone metabolites. In the luteal phase of the menstrual cycle, THDOC excretion was higher than in the follicular phase; it was also higher than in women taking oral contraceptives. The correlation of THDOC with progesterone production, independent of a constant cortisol output, supports an ovarian or peripheral conversion of progesterone to DOC. The assay proved useful (1) in monitoring for the recurrence of a mineralocorticoid-secreting tumor and (2) when adrenal production of DOC was not fully suppressed in congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency. Under the latter circumstances, the renin-angiotensin system seemed to be an important regulator of DOC production.

The analysis of trenbolone and the human urinary metabolites of trenbolone acetate by gas chromatography/mass spectrometry and gas chromatography/tandem mass spectrometry

The electron impact mass spectrometric properties of trimethylsilyl ether and fluoroacyl ester derivatives of trenbolone, combined or not combined with a methoxime group, are presented. Some derivatization problems were observed and were due to the formation of enol derivatives at the 3C-position in several tautomeric forms, which in their turn were not stable and lost two or four hydrogens under the conditions studied. The enolization could be minimized by carefully selecting the reaction conditions or could be prevented by the introduction of a methoxime group at the 3C-position. The limits of detection and identification of the methoxime heptafluorobutyryl ester and the methoxime trimethylsilyl ether derivative of trenbolone were determined using a mass selective detector in the electron impact mode and a triple-stage quadrupole in the methane positive chemical ionization mode. Selected reaction monitoring in tandem mass spectrometry did not improve the limit of detection, but because of the gain in selectivity did improve the limit of identification. The glucuronides of trenbolone and epitrenbolone could be identified in three urine specimens out of 200 samples in routine doping control.

A gas chromatographic method for the determination of neutral steroid profiles in urine, including studies on the effect of oxytetracycline administration on these profiles in men

A capillary gas chromatographic method for the determination of 'total' metabolic profiles of urinary neutral steroids was developed. The method is based on anion exchange chromatographic separation and purification of monoglucuronide-, monosulphate- and double-conjugated neutral steroids on DEAE-Sephadex A-25 microcolumns and the final analysis of the individual steroids in these conjugate groups is carried out by capillary column gas-liquid chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The method was shown to provide a convenient and accurate determination of total metabolic profiles of neutral steroids in urine and thus, can be used for metabolic studies of steroids and for diagnostic purposes. In the present investigation the effect of a tetracycline antibiotic on the production and metabolism of neutral steroids in men was studied during a 5-day oral administration of oxytetracycline. The results showed that the influence of oxytetracycline on neutral steroids was minor and mainly restricted to the changes in urinary neutral steroid glucuronide excretion. Oxytetracycline decreased the mean daily excretion of total neutral steroid monoglucuronides by 20% and a statistically significant decrease was found in the urinary excretion of 3 alpha-hydroxy-5 beta-androstan-17-one-glucuronide (etiocholanolone, 31%, P less than 0.05), 5 beta-pregnan-3 alpha,20 alpha-diolglucuronide (pregnanediol, 32%, P less than 0.05) and corticosteroid glucuronides, including 3 alpha,11 beta,17 alpha,20 beta,21-pentahydroxy-5 beta-pregnan- and 3 alpha,17 alpha,20 beta,21-tetrahydroxy-5 beta-pregnan-11-one-glucuronides (beta-cortol and beta-cortolone, 36%, P less than 0.05). The reason for this effect is unknown, but may be partly due to inhibition of intestinal hydrolysis of biliary steroid conjugates, which previously was shown to result in an interruption of enterohepatic circulation of steroids and an increased excretion of steroid conjugates by the faecal route.

Test strip enzyme immunoassays and the fast screening of nortestosterone and clenbuterol residues in urine samples at the parts per billion level

The preliminary results of an investigation into the development of "on-site" test strip enzyme immunoassays for the screening of urine samples for the presence of growth promoters, such as 17 beta, 19-nortestosterone and clenbuterol at the parts per billion level are described. Urine samples, enzyme-labelled analyte and a nitrocellulose test strip, containing immobilized antibodies, are incubated together, after which the strip is placed in a chromogen-containing substrate solution for colour reaction. Using prefabricated strips, the tests can be performed in 45-60 min. A similar assay was worked out using a dot-blotting device, allowing the test to be performed in 20-50 min. The tests are simple and easy to perform outside the laboratory. Urine samples identified positive by gas chromatography mass spectrometry were also found to be positive with these test strips and, so far, no false-positive results have been encountered. With standard additions to blank urine samples, positive samples could be distinguished above the 5 ng ml level. However, samples from treated calves contain one or more metabolites of the parent compound, which increase the sensitivity of the assays. Although the tests described can be improved and still have to be evaluated further by analysing more urine samples, the preliminary results are very promising and give a lead to further research into the applicability of such "on-site" tests in residue analysis.

The determination of 11 beta-hydroxyandrostenedione in human follicular fluid and plasma

The development of a chromatographic/immunoassay method is presented for the measurement of 11 beta-hydroxyandrostenedione (11 beta-OH-A4) in ovarian follicular fluid (FFL) and plasma from women undergoing embryo transfer for in vitro fertilization. This method incorporates high-performance liquid chromatography (HPLC) and permits the simultaneous measurement of other steroids from a single sample in order to assess the intraovarian environment. Authenticity of 11 beta-OH-A4 in follicular fluid was confirmed using selected ion monitoring (SIM) gas chromatography/mass spectrometry (GC/MS). Our results demonstrate a mean concentration of 18.6 nmol/l in follicular fluid compared with 3.2 nmol/l in plasma. The origin of 11 beta-OH-A4 in follicular fluid requires further investigation but these findings supports the hypothesis of ovarian 11 beta-hydroxylase activity on C19 steroids.

Severe hypoaldosteronism due to corticosterone methyl oxidase type II deficiency in two boys: metabolic and gas chromatography-mass spectrometry studies

Infection-triggered, life-threatening salt-loss and hyperkalaemia developed in two male infants with wasting, inappropriately low plasma aldosterone concentrations and elevated plasma renin activity. The presumptive diagnosis of a defective terminal step in aldosterone biosynthesis was made by the presence of large amounts of 11-dehydrotetrahydrocorticosterone and its 18-hydroxylated metabolite (18-OH-THA), free 18-hydroxycorticosterone (18-OH-B) and 18-hydroxytetrahydrocorticosterone in the urine of both patients. The diagnosis of corticosterone methyl oxidase type II (CMO II) deficiency was confirmed by an elevated urinary 18-OH-THA to tetrahydroaldosterone ratio in one boy and by an elevated plasma 18-OH-B to aldosterone ratio in the other boy. Unknown steroids responsible for the salt-loss were not identified. Sodium supplementation but not short-term high dose oral 9 alpha-fluorcortisol (FF) normalized the hyponatraemia in one patient, in whom sodium (Na+)/potassium (K+) co-transport was decreased. Both patients eventually received long-term FF treatment to prevent impairment of longitudinal growth caused by chronic salt-loss. The diagnosis of CMO II deficiency should always be confirmed by elevated precursor-product ratios in urine or plasma, using radioimmunoassays with prior chromatographic separation. Metabolic studies as the short-term response of serum Na+ to high dose FF may not be helpful in differentiating aldosterone biosynthetic defects from end-organ resistance to mineralocorticoids.

Metabolites of estradiol in serum, bile, intestine and feces of the domestic cat ()

We wished to develop an efficient, noninvasive method for monitoring ovarian function in domestic and nondomestic Felidae. We hypothesized that the method could be based on measurement of one of the major excreted estrogen metabolites. To identify and characterize the major excreted metabolites, a bolus of (14)C-estradiol was administered into the femoral vein of adult female cats. We measured the amounts of total radioactivity per unit time contained in unconjugated and conjugated estradiol metabolites, in conjugated metabolites that were hydrolyzable, and in those not hydrolyzable by beta Glucuronidase / aryl sulfatase (the enzyme). Radionuclide levels were determined in voided feces and urine, in jugular vein plasma, bile, contents of the duodenum, and in the small intestine. Metabolites of (14)C-estradiol were voided preferentially in feces and in equal amounts either as unconjugated estradiol or as conjugates not hydrolyzable by the enzyme. In plasma, conjugated estrogens comprised an increasing proportion of the total radioactivity during the first 40 min after administration. Plasma pools of samples from 0.5 to 30 min and 40 to 360 min contained a monoconjugate and a diconjugate, respectively; both were hydrolyzable by the enzyme. Bile and intestinal samples were collected at 360 min after administration. In the bile, 99% of the total radioactivity was in conjugated compounds, only 20% of which were not hydrolysable by the enzyme. The proportion of unconjugated metabolites increased to 18% in the duodenum and to 45% in the small intestine. The major conjugates contained in voided feces not hydrolyzable by the enzyme were estradiol sulfate (m/z = 351.6836), distributed as the 3-sulfate (20%) and 17-sulfate (80%); of the latter, 70% were 17alpha- and 30% 17beta-estradiol sulfates. These data document the fate of estradiol in the circulation of the cat, they demonstrate that a large portion of the voided estradiol metabolites are not hydrolyzable by the enzyme, and account for those conjugates previously termed nonhydrolyzable.

Adrenal function in asthma

A dose dependent suppression of daily cortisol excretion was shown in 25 children with asthma being treated with beclomethasone dipropionate. Cortisol metabolites tended to occur below the normal range when doses of beclomethasone of more than 400 micrograms/m2/day were given. Androgen excretion below the normal range was apparent in asthmatic children aged 8-13 years regardless of whether they were receiving inhaled steroids. This may be the reason for growth delay often seen in asthmatic children. These side effects of beclomethasone are not enough reason to discourage its prescription for the treatment of asthma, but endocrine assessment is desirable when the dose exceeds 400 micrograms/m2/day.