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Clinical and biochemical investigation of a virilized woman has shown an adrenal cortical adenoma to be the source of elevated plasma testosterone levels and to be responsive to gonadotropin administration in vivo (Givens et al.) (2). In the present study, the gonadotropin responsiveness and biosynthetic potential of the adenoma were evaluated in vitro . Incubation of minced adrenal tumor with hCG resulted in increased 14C-acetate incorporation into pregnenolone, progesterone, dehydroepiandrosterone (DHA), androstenedione, and testosterone. Androstenedione and testosterone were the major products, accounting for 27% and 20% respectively of the total radio-activity added, when 3H-pregnenolone was incubated with homogenized tissue. Estrogen synthesis was not observed in the tumor. The adenoma contained 9.0 μg/g testosterone and 1.9 μg/g androstenedione as determined by radio immunoassay. 17β-hydroxysteroid oxido-reductase was active in the adenoma. Androstenedione was reduced to testosterone at a rate of 0.6 μg/100mg/hr. Under the same conditions, reduction of estrone to estradiol was undetectable. The reductase activity was present in both the mitochondrial and microsomal fractions. NADPH was the required cofactor. When NADH was substituted, the rate was less than 10% of that with NADPH in both particulate fractions. The experimental results indicate the presence of steroid path-way(s) necessary to synthesize testosterone, and represent the first in vitro demonstration of gonadotropin sensitive steroidogenesis in an adrenal cortical adenoma.

The metabolism of testosterone-4- 14 C by hamster skin and flank organ was studied; flank organ metabolized more testostrone than an equal weight of adjacent skin. Androstenedione, † androsterone, androstanedione, dihydrotestosterone (DHT), and 3α-androstanediol were identified by chromatography and reverse isotopic dilution as metabolites formed by flank organ. The metabolites of flank organ and general body skin showed identical chromatographic mobilities. Flank organ produced 4 times as much DHT as an equal weight of adjacent skin. The ratio of total 5α-metabolites formed by both tissues was the same as the DHT ratio, indicating that the greater amount of DHT formed is due to greater formation of 5α-metabolites, in general. In contrast, both tissues produced the same amount of 17-ketosteroids from testosterone and had similar DNA contents, suggesting that the observed difference in 5α-reduction was not due to differences in cellularity but to a greater capacity of the flank organ to reduce testosterone. No 3β-hydroxysteroids, the formation of which has been reported in human skin were found.

Dehydroepiandrosterone (DHA) augments the activity of human chorionic gonadotrophin (HCG) in the rat by increasing endogenous pituitary gonadotrophin secretion. The following experiments were undertaken to investigate the mechanism underlying this effect. Androstenedione (40 μg), dihydrotestosterone (200 μg) and testosterone (200 μg) augmented the rat uterine weight response to 0.5 IU of HCG. At these doses, the steroids did not affect basal uterine weight although this was increased when 1 mg of a steroid was injected. Androsterone (1 mg), 17α-hydroxypregnenolone (1 mg) and progesterone (200 μg) neither augmented HCG activity nor increased basal uterine weight. Ovarian weight differences were not significant in any of the experiments. Androstenedione, DHA, dihydrotestosterone and testosterone (200 μg dose level) did not significantly affect the uterine weight of castrated animals, and responses to 0.04 μg of oestradiol were not potentiated. The results with androstenedione, dihydrotestosterone and testosterone are identical to those obtained with DHA and suggest that these steroids may also increase pituitary gonadotrophin secretion.

This report describes a 17-yr-old female who developed acanthosis nigricans, hirsutism and amenorrhea concurrently at age 15. Plasma androstenedione (A) was extremely elevated ranging from 3500 to 5000 ng/100 ml. Plasma testosterone (T) and urinary 17-ketosteroids (17-KS) were also elevated at 357 ng/100 ml and 32–42 mg/24 hr respectively. Plasma A and T were not reduced by dexamethasone (Dex), but human chorionic gonadotropin (hCG) increased plasma A to 23,500 ng/100 ml, plasma T to 3666 ng/100 ml and the 17-KS to 156 mg/24 hr. Ethinyl estradiol (EE) plus Dex reduced LH to a nondetectable level, A to 72 ng/100 ml and T to 10 ng/100 ml. ACTH did not increase A or T. The patient was treated for 7 months with 0.15 mg/day of EE and there was marked improvement of the acanthosis nigricans associated with correction of the hyperandrogenism. Because of menorrhagia, EE was discontinued and the high levels of A and T returned and the acanthosis nigricans worsened. Exploratory laparotomy was performed and...

Different areas from brains of 7- day-old female rats were incubated with testosterone- 7-3H (T) or androstenedione- 1-23H (A). Hypothalami from 120-day-old females were also incubated with T. The conversion of these precursors to estradiol (E2) and estrone (E1) was studied using double isotope dilution technique. In addition, the conversion of E2 to E1 and E1 to E2 by brain of the immature females was studied. T was converted predominantly to E2 and A to E1. The yield of E2from T was greatest in incubations of hypothalamus and amygdala, less for the combined septal and preoptic areas and least for the cortex. Conversion of T to E2 by hypothalami of adult rats was less than by that from the immatures. The yield of E1 from A was also greater in hypothalamic than in cortical incubations. There was only minimal conversion less than 3%) of E2 to E1 and of E1, to E2.(Endocrinology 94: 616, 1974)

The annual reproductive cycle has been investigated in the male pipistrelle bat Pipistrellus pipistrellus. Spermatogenesis occurs during summer and spermatozoa are produced in August and September. The seminiferous tubules then regress rapidly but sperm are stored throughout winter in the cauda epididymidis. Little change is apparent in the morphology of the Leydig cells throughout the year, and histochemical studies have revealed no seasonal differences in the occurrence of enzymes involved in steroidogenesis. The percentage yields of testosterone and androstenedione after incubation of testis and adrenal tissues in vitro with tritiated pregnenolone have been determined and measurements made of the concentration of these hormones in testes and whole blood. Although the highest levels of these androgens are synchronous with spermatogenesis, both continue to be produced by the testes during winter. Studies in castrated bats have confirmed these observations and indicate that the activity of the accessory reproductive organs during winter is dependent on testicular androgens. The testicular cycle of the pipistrelle is not thought to be complicated by adrenal androgenesis, or storage of androgens in the brown fat. The interrelationships between reproduction and hibernation in bats are discussed.

Female rats were implanted on the day of birth with Silastic capsules containing nonesterified testosterone, androstenedione, or dihydrotestosterone. The date of vaginal opening was assessed until sacrifice. The animals were ovariectomized, treated with estradiol benzoate and progesterone, and tested for the display of lordosis. The animals were then administered testosterone propionate and the size of the phallus was taken. Testosterone and dihydrotestosterone completely inhibited vaginal opening; androstenedione was partially effective. Testosterone almost completely inhibited lordosis behavior; androstenedione was partially effective and dihydrotestosterone was ineffective. All three androgens facilitated phallic development.

The pinneal organs of orchiectomized rats incubated in vitro with 3H-testosterone took up and retained 3H-radioactivity up to a tissue concentration 18-fold that of the incubation media. Maxima in tissue/medium ratios (T/M) were observed after 2-hr incubations at 37 C. Pineal organs of castrated rats exhibited higher T/M ratios than sham-operated controls. Pineal T/M ratio was 8- and 6-fold that of the cerebral cortex and tibial muscle, respectively, and about half that of the prostate. Testosterone, β-hydroxy-5α-androstan-3-one, 5α-androstane-3α, 17β-diol, androstenedione, and 5α-androstane-3, 17-dione were identified in the incubated rat pineals by thin-layer chromatography and recrystallization to constant specific activity. At low concentrations of testosterone (up to 2 × 10−11 M), T/M ratios for 3H-radioactivity depended upon the concentration of the hormone in the incubation medium. At higher concentrations pineal T/M ratio remained constant regardless of the concentration of testosterone in the med...

Two 46 XY siblings with familial incomplete male pseudohermaphroditism, Type 2, inherited as an apparent autosomal recessive trait, were investigated. The phenotype was distinctive in that male wolffian-duct structures (epididymis, vas deferens and seminal vesicles) were present whereas tissues derived from the urogenital sinus and from the anlage of the external genitalia were female in character. Studies of estrogen and androgen dynamics revealed normal male blood testosterone and estrogen levels, production rates and interconversions. The normal blood luteinizing hormone level and normal estrogen production rate suggest that androgen resistance in this syndrome is different from that in other androgen-resistant states. The demonstration of markedly deficient dihydrotestosterone formation in slices of perineal skin, epididymis and phallus, considered with the fact that dihydrotestosterone is the fetal hormone responsible for male differentiation of the external genitalia, is compatible with the...

By judicious choice of the site of attachment of steroid haptens to a protein carrier it is possible to elicit the formation of antibodies with enhanced specificity towards selected parts of the steroid molecule. Coupling the steroid through a position remote from the functional groups responsible for its hormonal specificity preserves these substituents as antigenic determinants. This has been effected in gonadal steroids by inserting “chemical handles” (e.g. carboxymethyl oxime, carboxyethyl thioether or hemisuccinate groups) into the steroid skeleton at positions 1,6,7 or 11. Thus, immunization with oestrone, oestradiol-17β or oestriol coupled to protein at position 6 gave rise to antibodies discriminating between the three major oestrogenic hormones and closely related metabolites that are not distinguished by antibodies to oestrogens conjugated to protein at C-17. Likewise, antibodies to progesterone-6-, 7- or 11-conjugates recognize changes in the 17-sidechain more efficiently than antibodies to the corresponding 20-conjugate. However, the antiserum to progesterone-6—protein was least specific towards changes in the A-ring. This approach has been extended to key progesterone metabolites and to androgens. Thyroglobulin or BSA conjugates of 1-carboxyethyl thioethers of testosterone, 5α-dihydrotestosterone (DHT), androstenedione (Ad) and progesterone have been prepared. Antisera reacting preferentially with DHT, and antisera to testosterone showing minimal cross-reaction with DHT (8 %) and none with Ad (

SUMMARY The concentrations of luteinizing hormone (LH), progesterone, testosterone, androstenedione, oestrone and oestradiol in mixed umbilical cord blood taken from foetal calves during months 3 to 9 of gestation have been measured by radioimmunoassay. The levels of progesterone were low (compared with those in maternal plasma) and constant during pregnancy. There were large variations in the concentrations of androstenedione, oestrone, oestradiol and LH, with lower values found during months 7 to 8 of gestation. Significant differences (P < 0·05–< 0·001) in hormone levels between male and female foetuses were found for testosterone, LH, and the oestrogens during months 3 to 7, 3 and 4, and 7 and 8, respectively. No significant differences (P > 0·05) between sexes were found at any time between the concentrations of progesterone and androstenedione.

To investigate the mechanism of the increased plasma estradiol levels in spontaneous hyperthyroidism, the contribution, by peripheral conversion, of androstenedione and testosterone to the circulating estrogens was determined. The conversion ratio of androstenedione to estrone was significantly increased in both males and females (0.0396 and 0.0256, respectively). The conversion ratio of androstenedione to estradiol was increased in the male (0.0094) but not in the female (0.0051) patients. The conversion ratio of testosterone to estrone was increased in both males (0.0072) and females (0.0070). The conversion of testosterone to estradiol, however, was not increased in either sex. The plasma concentration of androstenedione was significantly increased (0.34 μg/100 ml) in the male patients with hyperthyroidism. However, the production rate of androstenedione was increased in both sexes (8.59 and 6.72 mg/day). The contribution of testosterone and androstenedione to plasma estrone and estradiol (pro...

In vitro steroid biosynthesis in the male and female gonad of Mytilus edulis was investigated. Using tritium and 14C-labeled precursors, four enzyme systems were demonstrated: a 3β-hydroxysteroid dehydrogenase-Δ5,4-isomerase comples (pregnenolone→progesterone; 17α-hydroxypregnenolone→17α-hydroxyprogesterone; dehydroepiandrosterone→androstenedione), a C17,20-lyase (17α-hydroxypregnenolone→dehydroepiandrosterone; 17α-hydroxyprogesterone→androstenedione), a 17β-hydroxysteroid dehydrogenase (dehydroepiandrosterone→androstenediol; androstenedioneαtestosterone; estradiol-17βαestrone) and a 5α-reductase (testosterone→5α-dihydrotestosterone). The yields were very low (0.2–1%) except when estrogens were used (10–50%). Radioimmunoassay techniques indicate the presence of testosterone and possibly estrogens in the gonad of the mussel at two different stages in its gametogenic cycle.

A family with incomplete male pseudohermaphroditism inherited as an apparent X-linked recessive trait was investigated. The phenotype in 11 affected family members ranged from a minimal de...

SUMMARY Human skin from forehead, cheek and axilla was incubated in vitro with [7α-3H]dehydroepiandrosterone (DHA), [7α-3H]DHA sulphate, [7α-3H]-androstenedione and [7α-3H]testosterone. The following enzyme activities were detected: 3β-hydroxysteroid dehydrogenase Δ4-5 isomerase, 17β-hydroxysteroid dehydrogenase, 3β-hydroxysteroid dehydrogenase, 3α-hydroxysteroid dehydrogenase, 5α-reductase, 5β-reductase, sulphotransferase, sulphatase, steroid hydroxylase. 5α-Reduced steroids were the major metabolites. All four substrates were converted to 5α-dihydrotestosterone and 5α-androstane-3α,17β-diol. In axillary skin, conversion of 17-oxosteroids to 17β-hydroxysteroids was favoured, 5α-dihydrotestosterone and 5α-androstane-3α,17β-diol being major metabolites. In facial skin, formation of 17-oxosteroids predominated with little accumulation of 5α-dihydrotestosterone or 5α-androstane-3α,17β-diol. 5α-Androstane-3β,17β-diol was a metabolite of DHA, androstenedione and testosterone but was found in lower amounts than 5α-androstane-3α,17β-diol. Similarly conversions to epiandrosterone were much lower than to androsterone in all the skin specimens. It was concluded that the differences in accumulation of 5α-dihydrotestosterone were determined by the differences in 17β-oxidoreduction rather than differences in 5α-reductase, the activity of which was high in all skin specimens.