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3β-Hydroxysteroid dehydrogenase activity was studied histochemically in human, monkey, and rat adrenal glands and in human placentae. Tissue sections were incubated separately with each of the following substrates: (1) 3β-hydroxypregn-5-en-20-one (pregnenolone); (2) sodium 3β-sulphoxypregn-5-en-20-one (pregnenolonesulphate); (3) 3β-acetoxypregn-5-en-20 one (pregnenoloneacetate); (4) 3β,16α-dihydroxypregn-5-en-20-one (16α-hydroxypregnenolone); (5) 3β,17α-dihydroxypregn-5-en-20-one (17α-hydroxypregnenolone); (6) ammonium 3β-sulphoxy-17α-hydroxypregn-5-en-20-one (17α-hydroxypregnenolone ammonium sulphate); (7) 3β-hydroxyandrost-5-en-17-one (DHA); (8) 3β-sulphoxyandrost-5-en-17-one (DHA sulphate); (9) 3β-acetoxyandrost-5-en-17-one (DHA acetate); (10) androst-5-ene-3β, 17β-diol (androstenediol).

The histochemical results obtained with pregnenolone and DHA as substrates resemble those described by other workers. Using pregnenolone sulphate and 17α-hydroxypregnenolone sulphate, a strong histochemical reaction with diformazan deposition was found in the zona fasciculata of the adrenals of all species and in the placental syntrophoblast. With DHA sulphate an extremely weak histochemical reaction was obtained with the adrenal zona fasciculata, monoformazan only being deposited. The syntrophoblast, however, showed intense 3β-hydroxysteroid dehydrogenase activity when incubated with DHA sulphate. These results accord with recent findings regarding the secretion and metabolism of 3β-sulphoxysteroids.

A strong histochemical reaction was also obtained in both adrenal and placental tissues using 17α-hydroxypregnenolone, 16α-hydroxypregnenolone, androstenediol, pregnenolone acetate, and DHA acetate. These steroids have not previously been described as substrates for the histochemical demonstration of 3β-hydroxysteroid dehydrogenase in the adrenal or placenta.

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An ultramicrochemical technique has been applied to the study of the metabolism in vitro of [3H]DHA in the separated adult and foetal zones of the human adrenal gland. Evidence has been found for the formation of DHA sulphate and androstenedione in the adult and foetal zone, and whole adrenal gland preparations obtained from one newborn hydrocephalic infant and two mid-term foetuses, and also for the formation of 1 1β-hydroxyandrostenedione in the adult zone tissue from the hydrocephalic infant. In all experiments, more DHA was converted to DHA sulphate by the foetal zone (21–27% conversion) than by the adult zone (5–7% conversion), whereas more androstenedione was formed in the adult zone than in the foetal zone. At mid-term less than 0·6% of [3H]DHA was converted to androstenedione compared with 33 and 3·4% conversion by the adult and foetal zone tissue, respectively, from the hydrocephalic infant.

These results are discussed in relation to perfusion studies of the human foetus and previous in vitro and histochemical investigations of the human foetal adrenal gland.

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Sections of ovaries from 30 Swiss white mice were incubated with ten steroid substrates to demonstrate 3β-hydroxysteroid dehydrogenase activity histochemically. The substrates were: (1) 3β-hydroxypregn-5-en-20-one (pregnenolone), (2) 3β,17α-dihydroxypregn-5-en-20-one (17α-hydroxypregnenolone), (3) 3β-hydroxyandrost-5-en-17-one (DHA), (4) 3β,17β-dihydroxyandrost-5-ene (androstenediol), (5) 3β-sulphoxypregn-5-en-20-one (pregnenolone sulphate), (6) 3β-sulphoxy-17α-hydroxypregn-5-en-20-one (17α-hydroxypregnenolone sulphate), (7) 3β-sulphoxyandrost-5-en-17-one (DHA sulphate), (8) 3β-acetoxypregn-5-en-20-one (pregnenolone acetate), (9) 3β-acetoxyandrost-5-en-17-one (DHA acetate), and (10) 3β-acetoxy-17β-hydroxyandrost-5-ene (androstenediol acetate).

Pregnenolone, 17α-hydroxypregnenolone, DHA and androstenediol gave a colour reaction in the corpora lutea, interstitial tissue, theca interna and stroma of all ovaries examined. The granulosa of many follicles, some thought to be atretic, also contained diformazan granules. 17α-Hydroxypregnenolone did not give as intense a reaction as the other free steroids.

No diformazan was deposited with DHA sulphate as substrate. Pregnenolone sulphate and 17α-hydroxypregnenolone sulphate were used by the same tissues as were the free steroids, although they were much less well utilized.

Utilization of 3β-acetoxy derivatives was similar to that of the free steroids.

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V. E. Fantl and D. Y. Wang


Mice were immunized with a mixture of four steroid antigens: dehydroepiandrosterone (DHA), oestradiol, progesterone and testosterone linked to bovine serum albumin through the 7, 6, 11α and 17β positions respectively. The response to immunization varied widely with no one mouse producing an optimal response to all four steroids. In the two fusion experiments performed, antibodies to all four antigens were developed. Data are presented which show that the immune response of the spleen donor is related to the relative numbers and quality of the antibodies produced to each steroid. Despite the structural identity of the progesterone and testosterone haptens, antibodies elicited in response to their respective antigens could readily be distinguished from each other.

From the large number of monoclonal antibodies obtained those most useful for radioimmunoassay were three high affinity antibodies to oestradiol and two antibodies raised against DHA but with high affinity for DHA sulphate.

J. Endocr. (1984) 100, 367–376

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Dehydroepiandrosterone (DHA), a weak androgen with a potency one-fifth of that of testosterone, stimulates thyroid activity (Tal & Sulman, 1972). The mechanism of this effect is studied in the present paper.

DHA (1, 5, 10, 20 or 50 mg/kg/day) was administered daily i.p. to 21-day-old male rats of the Hebrew University Sabra strain. The rats received standard Purina chow and water ad libitum, were kept in a room at 23 ± 1 °C with artificial lighting for 12 h daily, and were killed after 21 days of treatment. DHA was also implanted stereotaxically (Mess, 1967) in the anterior basal hypothalamus of 42-day-old male rats (5 μg/rat), the pellets being ejected into the tissue from Rudmond's disposable glass micro-tubings and their location later confirmed histologically. The site chosen was A = 0, L = 0, H = -8 (König & Klippel, 1963). The rats were killed by decapitation 4, 24, 48 or 72 h

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The metabolism of [7α-3H]dehydroepiandrosterone (DHA) and [4-14C] androstenedione in vitro was investigated in 30-day-old (prepubertal) and adult rat testicular tissue in the presence of cyanoketosteroid, a 5-ene-3β-hydroxysteroid oxidoreductase inhibitor.

Whereas both substrates were converted to 5α-reduced steroids by the prepubertal testis, 4-ene-steroid-5α-reductase activity was negligible in the adult gland. Cyanoketosteroid prevented the formation of 5α-reduced steroids from DHA by the prepubertal testis indicating testosterone and androstenedione as intermediates in their production.

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The localization of enzymes required for dehydroepiandrosterone sulphate (DHAS) biosynthesis from pregnenolone in human foetal adrenal glands was investigated using a microtechnique to obtain serial tissue sections through the glands.

Both zones of the adrenal glands converted pregnenolone to pregnenolone sulphate and to 17α-hydroxypregnenolone, dehydroepiandrosterone and their sulphates. A higher conversion to the steroid sulphates was found in the foetal compared with the adult zone tissue incubations. In two experiments, the highest conversion to DHAS occurred with tissue from the foetaladult border zone. The relative amounts of the steroids formed during incubation with whole gland homogenates were similar to those formed in the incubations of the foetal zone.

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The levels of pregnenolone, dehydroepiandrosterone (DHA), androstenedione, testosterone, dihydrotestosterone (DHT), oestrone, oestradiol, cortisol and luteinizing hormone (LH) were measured in the peripheral plasma of a group of young, apparently healthy males before and after masturbation. The same steroids were also determined in a control study, in which the psychological anticipation of masturbation was encouraged, but the physical act was not carried out. The plasma levels of all steroids were significantly increased after masturbation, whereas steroid levels remained unchanged in the control study. The most marked changes after masturbation were observed in pregnenolone and DHA levels. No alterations were observed in the plasma levels of LH.

Both before and after masturbation plasma levels of testosterone were significantly correlated to those of DHT and oestradiol, but not to those of the other steroids studied. On the other hand, cortisol levels were significantly correlated to those of pregnenolone, DHA, androstenedione and oestrone.

In the same subjects, the levels of pregnenolone, DHA, androstenedione, testosterone and DHT in seminal plasma were also estimated; they were all significantly correlated to the levels of the corresponding steroid in the systemic blood withdrawn both before and after masturbation.

As a practical consequence, the results indicate that whenever both blood and semen are analysed, blood sampling must precede semen collection.

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The pattern of metabolites present in human benign prostatic tissue after infusion of either [7α-3H]testosterone, [7α-3H]androstenedione or [7α-3H]dehydroepiandrosterone (DHA) sulphate 30 min before prostatectomy were investigated. Infusion of [7α-3H]testosterone yielded 5α-dihydrotestosterone (17β-hydroxy-5α-androstan-3-one) as the major metabolite present in the prostatic tissue together with other 5α-androstane compounds. The major radioactively labelled steroids identified in the prostatic tissue after [7α-3H]androstenedione infusion were epiandrosterone and androsterone, and dehydroepiandrosterone after [7α-3H]DHA sulphate infusion, although various other 5α-androstane compounds were also present after both infusions. The proportion and identity of radioactive steroids present in the epithelial and stromal portions of the tissue after in-vivo infusion of [7α-3H]testosterone was investigated. Also the ability of separated epithelial and stromal elements of prostatic tissue to metabolize steriods in vitro was studied. Dehydroepiandrosterone sulphate and DHA metabolism in vitro by minced human prostatic tissue yielded various 5α-androstane compounds in addition to DHA and androstenediol (androst-5-ene-3β,17β-diol).

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EJ Giltay, EJ Duschek, MB Katan, PL Zock, SJ Neele, and JC Netelenbos

Estrogens may affect the essential n-6 and n-3 fatty acids arachidonic acid (AA; C20:4n-6) and docosahexaenoic acid (DHA; C22:6n-3). Therefore, we investigated the long-term effects of hormone replacement therapy and raloxifene, a selective estrogen-receptor modulator, in two randomized, double-blind, placebo-controlled studies. In study I, 95 healthy, non-hysterectomized, early postmenopausal women (age range 47-59 years) received one of the following treatments: daily raloxifene 60 mg (n=24), daily raloxifene 150 mg (n=23), 0.625 mg conjugated equine estrogens (CEE) plus 2.5 mg medroxyprogesterone acetate (MPA; n=24), or placebo (n=24). In study II, 30 men (age range 60-69 years) received daily 120 mg raloxifene (n=15) or placebo (n=15). In study I, plasma cholesteryl ester fatty acids were measured at baseline and after 6, 12, and 24 months in 83 (drop out rate 13%), 73 (23%), and 70 (25%) women respectively. In study II, fatty acids were measured at baseline and after 3 months in 29 men (drop out rate 3%). In postmenopausal women, administration of 150 mg raloxifene increased AA by a mean of +6.1% (P=0.055, not significant). Administration of CEE plus MPA increased AA by +14.1% (P<0.0005). Mean changes in DHA were +22.1% (P=0.003) and +14.9% (P=0.047) respectively, as compared with placebo. In men, 120 mg raloxifene for 3 months did not significantly affect AA (-5.2%; P=0.342) or DHA (+4.0%; P=0.755), but it increased testosterone levels by +19.8% (P=0.006). Administration of raloxifene 150 mg/day as well as CEE plus MPA to postmenopausal women increases the proportion of AA and DHA in plasma cholesteryl esters during a follow-up of 2 years. Short term administration of raloxifene in elderly men did not affect AA or DHA. The synthesis of AA and DHA from precursors may be enhanced through an estrogen receptor-dependent pathway.