The syndromes of androgen resistance revisited

A revisit to the existing complexities of the androgen resistance syndromes within the frame of our current knowledge was undertaken. Recent contributions of these and other laboratories are presented according to the topographic intracellular location of the underlying abnormalities causing these inherited disorders. Thus, the clinical spectrum, inherited pattern and biochemical features of defective androgen action at the pre-receptor, receptor, and post-receptor levels are examined. In addition, the effects of androgens on the development of gender role is discussed, with particular focus on patients with pre-receptor defects. It was concluded that a better understanding of the nature of the altered events in these syndromes has been achieved over recent years, although several important issues still remain unsolved.

Induced hyperprolactinaemia does not alter FSH binding or ABP secretion in the rat testis

The effects of induced hyperprolactinaemia in male Wistar rats were studied by grafting two pituitary glands under the kidney capsule. Transplants were performed at 15 and 60 days of age, and rats killed 4 weeks later when tissue and serum samples were obtained. Serum concentrations of LH were reduced significantly in rats grafted at 60 days of age, whereas no change was observed in rats grafted at 15 days of age. Serum testosterone levels were slightly suppressed only in the older group of grafted rats. Testicular FSH receptors and the epididymal content of androgen-binding protein (ABP) were not modified by induction of hyperprolactinaemia. The results indicate that hyperprolactinaemia was not associated with changes in at least two functional parameters of the tubular compartment of the rat testis.

Binding and effects of catecholestrogens on adenylate cyclase activity, and adrenoceptors, benzodiazepine and GABA receptors in guinea-pig hypothalamic membranes

Catecholestrogen (CE) binding to guinea-pig hypothalamic membranes was assessed by using [3H]2-hydroxyestrone (2-OHE1) as a ligand. Binding was maximal at pH 7.4 and 37 degrees C, and after 10 min incubations. A high affinity binding site with dissociation constant (KD) = 0.20 +/- 0.02 nM and site concentration (Bmax) = 38 +/- 2 fmol/mg protein, and a low affinity binding site with KD = 235 +/- 10 nM and Bmax = 4.2 +/- 1.0 pmol/mg protein (n = 7) were detected. The order of affinity (Ki, microM) for displacement of 10 nM [3H]2-OHE1 from hypothalamic binding sites was 2-OHE1 (0.8), 2-hydroxyestradiol (2-OHE2) (1.0), epinephrine (5.9), norepinephrine (NE) (7.7), dopamine (270), estradiol, estrone, propranolol, phentolamine, domperidone (greater than 10 000). NE inhibition of 2-OHE1 binding was non-competitive, Only 0.5 mM 2-OHE2 depressed in a non-competitive way the hypothalamic beta-adrenoceptor binding (measured by using [3H]dihydroalprenolol) without affecting alpha-adrenoceptor binding (measured by using [3H]dihydroergocryptine). Both 2-OHE2 and 2-OHE1 impaired NE-stimulated adenylate cyclase activity in hypothalamic membranes with EC50 of about 5 and 10 microM, respectively. CE decreased [3H]gamma-aminobutyric acid binding by hypothalamic membranes with Ki = 8 microM (2-OHE2) and 50 microM (2-OHE1). The binding of [3H]flunitrazepam to the same membrane preparation was not affected by CE. These results support the existence of significant CE binding and effects in guinea-pig hypothalamic membranes.

Endocrine evaluation in a patient with MURCS association and ovarian agenesis

A new case of Mullerian duct aplasia, renal aplasia, and cervicothoracic somite dysplasia (MURCS association) in a 16-yr-old female patient is reported. In addition, agenesis of the right ovary plus hypoplasia of the right craniofacial bones were also present. Dynamic tests of anterior pituitary reserve (LH-RH, TRH and hypoglycemia) showed normal responsiveness of this gland in terms of LH, FSH, TSH, prolactin and growth hormone secretion, whilst a subnormal plasma cortisol response to hypoglycemia and exogenous ACTH (in the presence of unilateral adrenal agenesis) was found. Functional integrity of the hypothalamic-pituitary-ovarian axis was also documented. The presence of two additional and previously unreported congenital anomalies in this patient with MURCS association underlines the wide spectrum of the syndrome.

A-ring reduction enhances the antigonadotropic potency of norethisterone

To assess whether structural modifications on the A-ring of norethisterone (NET) could modify its antigonadotropic potency, comparative studies using NET, 5 alpha-dihydro NET (5 alpha-NET) and its 3 beta,5 alpha and 3 alpha,5 alpha tetrahydro derivatives in castrated adult rats were undertaken. The antigonadotropic effect of these compounds was evaluated by measuring the serum and pituitary immunoreactive concentrations of LH and FSH following their chronic sc administration to animals depleted of progesterone receptors. The results demonstrated that 3 beta,5 alpha-NET and 5 alpha-dihydro-NET exhibited a significantly greater gonadotropic inhibiting activity as compared with that of their parent compound. The simultaneous administration of tamoxifen with 3 beta,5 alpha-NET resulted in a significant diminution of its antigonadotropic potency, particularly for LH. These data indicate that the potent antigonadotropic effect of 3 beta,5 alpha-NET metabolite was mediated via oestrogen receptors. The LH inhibitory activity of 5 alpha-dihydro-NET was not suppressed by the non-steroidal antioestrogen administration, thus suggesting that 5 alpha-NET might exert its effect via androgen receptors. The overall data were interpreted as demonstrating that metabolic conversion products of NET exhibit potent antigonadotropic effect. The data are consistent with an A-ring enhancement of the antigonadotropic potency of this synthetic progestin and open an alternate approach to the development of fertility regulating agents.

Prediction and detection of ovulation by the measurement of urinary pregnanetriol-3 alpha-glucuronide. A multicentre study

The urine excretion pattern of pregnanetriol 3 alpha-glucuronide (PT-3G) throughout the menstrual cycle in 26 normal ovulating women was evaluated in a multicentre study. The concentration of PT-3G was measured by radioimmunoassay in daily samples of early morning urine (EMU) from 20 women for three consecutive cycles and from 6 women who conceived during the period of study. PT-3G was also measured in 24-h urine samples from 5 additional women. The peak of urine LH was used as a reference point for ovulation (Day 0). The EMU concentration of PT-3G in the follicular phase of 60 normal ovulatory cycles was 5.10 mumol/l +/- 0.11 (arithmetic mean +/- SE). The first PT-3G defined rise (CUSUM analysis) occurred during the late follicular phase (Days -3 to 0) with a PT-3G maximum excretion (9.69 mumol/1 +/- 0.55) on Day 0, whereas a PT-3G excretion peak occurred during mid-luteal phase (Days +5 to +9). The overall PT-3G excretion during the luteal phase (8.06 mumol/1 +/- 0.17) was significantly higher than that of the follicular phase (P less than 0.001). A further sustained increase in PT-3G excretion was noted after day +11 in the conceptional cycles. The 24-h excretion profile of PT-3G was similar to that obtained in EMU samples. No inter-centre significant variation was noticed in terms of PT-3G concentration values. The results were interpreted as demonstrating that the PT-3G excretion profile throughout the cycle exhibits a close resemblance to that of serum 17-OH progesterone. The data also indicates that although the immunoanalytical measurement of this urine steroid metabolite does not give an early sign for the occurrence of ovulation, it can be used for both the immediate prediction and the detection of ovulation.

Evidence that a non-aromatizable metabolite of norethisterone induces estrogen-dependent pituitary progestin receptors

Neutral reduced metabolites of norethisterone (NET) specifically interact with intracellular estrogen receptors in target organs. To determine if this interaction can effectively initiate estrogen-dependent cellular responses, the effects of an A-ring-reduced NET derivative upon the induction of cytosol-located pituitary progestin receptors (PR) and uterine growth were studied in adult castrated female rats. Different doses of 17 alpha-ethynyl-5 alpha-estran-3 beta, 17 beta-diol (3 beta, 5 alpha-NET) were s.c. administered to ovariectomized animals for 6 days. 17 beta-Estradiol (E2) and oil-treated rats served as experimental controls. Pituitary PR were labeled in vitro by a post-gradient technique using [3H]ORG-2058 as the ligand. PR binding specificity was determined by the use of an excess of radioinert steroids. The results demonstrated that administration of 3 beta, 5 alpha-NET induced specific 8-9S pituitary cytosol PR in a dose-dependent manner. Binding properties of the 3 beta, 5 alpha-NET-induced progestin binding sites (Kd = 1.0 X 10(-9) M; NBS = 1.2 X 10(-9) M) appear indistinguishable from those induced by E2. In addition, 3 beta, 5 alpha-NET administration resulted in a significant increase in uterine weight at the expense of myometrium and endometrium growth in a similar fashion to that observed in the E2-treated group. When 3 alpha, 5 alpha-epimeric alcohol (3 alpha, 5 alpha-NET) was administered, induction of pituitary PR and uterine growth were also observed although to a lesser extent. Inasmuch as the results demonstrate that neutral non-aromatizable NET metabolites induce biochemical and morphological estrogenic responses, they offer an alternative explanation for the mechanism of estrogen-like action of this synthetic contraceptive progestin.

The presence of Müllerian remnants in the complete androgen insensitivity syndrome: a steroid hormone-mediated defect?

A new patient with CAIS who presented Müllerian remnants has been described. Based on recently reported data in experimental animals and considering that human embryos carrying the X-linked CAIS mutation do not express any androgenic effect, we propose that the unopposed estrogenic action in the CAIS-developing embryo might interfere with the mechanism of action of the AMH inhibiting the regression of the female ducts.

Self-priming effect of luteinizing hormone-human chorionic gonadotropin (hCG) upon the biphasic testicular response to exogenous hCG. I. Serum testosterone profile

The present study was conducted to investigate whether the early (2-8 h) testicular response to a single dose of exogenous hCG depends on previous exposure to LH activity. Four different groups of subjects were studied: 1) four normal adult men [Tanner stage-G5 (T-G5)] and one late pubertal subject (T-G4); 2) normal prepubertal (T-G1) and early- and midpubertal boys (T-G2 and T-G3) (n = 4-6 each); 3) five patients with hypogonadotropic hypogonadism (HH); and 4) two patients with the complete form of the androgen insensitivity syndrome. Each subject received an im injection of hCG (40 IU/kg) on day 1 and blood samples were drawn before and 1-8, 24, 48, and 72 h after injection. At 96 h, a second dose of hCG was given (80 IU/kg) and blood samples were obtained at the same times as after the first hCG dose. Serum testosterone (T) was measured by RIA. The first dose of hCG evoked a biphasic response of serum T in groups T-G2 to T-G5 as well as in the two patients with the complete form of the androgen insensitivity syndrome. The early peak was at 2-7 h, whereas the late T peak was at 48-72 h after injection. In T-G1 children and in patients with HH, the early response did not occur [T-G1, from 129 +/- 43 (SEM) to 288 +/- 127 pg/ml (P greater than 0.05); HH, 79 +/- 18 to 107 +/- 12 (P greater than 0.05) pg/ml], and the late peak was attenuated as compared with the pubertal boys. There were not significant differences in the responses of the T-G1 and the HH groups. After the second dose, all groups had biphasic T responses, although they varied in magnitude. These results demonstrate that previous exposure to LH activity is an obligatory prerequisite for the early peak of the hCG-mediated biphasic testicular response, and that a single dose of hCG has a priming effect that is sufficient to ensure a biphasic response to a second dose of hCG given 96 h later.

Endocrine and biochemical studies in a 46,XY phenotypically male infant with 17-ketosteroid reductase deficiency

A 46,XY phenotypically male patient with 17-ketosteroid reductase deficiency is described. The patient was a 6-month-old infant who presented with micropenis and bilateral cryptorchidism. Baseline plasma levels of testosterone (T), delta 4-androstenedione (delta 4A), and 5 alpha-dihydrotestosterone (5 alpha-DHT) were within the normal range [patient: 0.17 (T), 0.12 (delta 4A), and 0.032 (5 alpha-DHT) ng/ml; normal infants: 0.03-0.55 (T), 0.14-0.45 (delta 4A), and 0.01-0.23 (5 alpha-DHT) ng/ml]. hCG administration induced a significant rise in plasma delta 4A levels (up to 8.39 ng/ml) and a slight increase in T and 5 alpha-DHT levels. The delta 4A/T ratios before and during the hCG challenge were 0.86 and 55.61, respectively (controls: 0.83 and 0.13). Incubation of genital skin-derived fibroblasts from the patient with either [3H]T or [3H] delta 4A revealed normal formation of delta 4A from T and diminished conversion of delta 4A to T. The development of a male phenotype despite both a testicular and peripheral 17-ketosteroid reductase deficiency is difficult to explain. It is possible that the fetal testes were the source of sufficient amounts of T during the early periods of embryonic life, and that late onset of the enzyme deficiency prevented the development of completely normal male genitalia. The in vitro finding of normal T to delta 4A conversion by the mutant fibroblasts suggests that in this particular tissue 17 beta-reduction and dehydrogenation of androgens are mediated by two isoenzymes with distinct substrate and/or cofactor specificities.

Endocrine and immunogenetic evaluation of an XX male infant with perineoscrotal hypospadias

To clarify the origin of the genital ambiguity occasionally associated with the XX male syndrome, a series of endocrinological studies were undertaken in an affected 6 months old infant with perineoscrotal hypospadias. The patient fulfilled all the diagnostic criteria of the syndrome: the testes were descended bilaterally, the Mullerian derivatives were absent, the 46,XX chromosome complement was ascertained in different cell lines, and male levels of H-Y antigen were detected in cultured skin fibroblasts. Circulating gonadotrophin levels and pituitary LRH responsiveness were within normal limits for the age group. Serum testosterone (T) levels were normal, and gonadal stimulation with hCG caused a significant rise on serum T. Incubations of [3H]T with fibroblasts from genital skin revealed normal activity of steroid 5 alpha-reductase. Moreover, normal concentrations of thermostable cytosol androgen receptors were revealed in cultured fibroblasts. Altogether the results indicated that ambiguity of the external genitalia in this patient was the result of neither abnormal T biosynthesis, peripheral A-ring T reduction, nor androgen intracellular specific binding, and suggested that the nature of the incomplete virilization could be a non-endocrine independent event associated to this disorder. The data are also consistent with the notion that testicular impairment observed in adult XX males develops later in life.

Stereospecificity of the intracellular binding of norethisterone and its A-ring reduced metabolites

The interaction of norethisterone (NET) and four A-ring reduced metabolites of NET with cytosol receptors for progesterone (PR), androgen (AR), and estrogen (ER) was investigated. Cytosol preparations from: uteri of adult estrogen-primed castrated rats, ventral prostates of adult castrated rats and uteri of immature rats were used as the source of PR, AR, and ER respectively. 3H-Labeled ORG-2058, R-1881, and 17 beta-estradiol were used as the radioligands. The results of competitive studies disclosed that: the most efficient competitor for PR binding sites was NET (Ki = 1.1 X 10(-7) M) followed by 5 alpha-dihydro NET (5 alpha-NET), whereas the 3 alpha,5 alpha; 3 beta,5 alpha and 3 alpha,5 beta-tetrahydro NET derivatives were ineffective the most efficient competitor for AR binding sites was 5 alpha-NET (Ki = 1 X 10(-8), immediately followed by NET, while the three tetrahydro NET derivatives were not competitors and remarkable competition for ER binding sites was only exhibited by the 3 beta,5 alpha-tetrahydro NET derivative (Ki = 4.6 X 10(-8) M) and to a lesser extent by its 3 alpha,5 alpha-epimeric alcohol, while NET and 5 alpha-NET were completely ineffective. These findings demonstrate the stereospecificity of the intracellular binding of NET and its reduced metabolites with cytosol steroid putative receptors, and provide biochemical support to the understanding of the variety of hormone-like effects observed after the in vivo administration of NET.

Estrogen-like effects of norethisterone on the hypothalamic pituitary unit of ovariectomized rats

The acute and chronic effects of norethisterone (NET) upon gonadotropin dynamics were studied in long-term ovariectomized adult Wistar rats. Time course studies showed that plasma LH declined within 1 h following a single NET sc injection and remained low for the next 4 h duration of the experiment. Pre-treatment with tamoxifen prevented the acute anti-gonadotropic effect of NET and GnRH administration to NET treated rats resulted in an abolishment of the pituitary responsiveness in terms of LH. Chronic administration of NET but not progesterone to castrated animals induced a significant decrease of plasma and pituitary LH with a concomitant replenishment of hypothalamic GnRH in an identical fashion to that observed with chronic administration of 17 beta-estradiol. Furthermore, administration of NET and 17 beta-estradiol but not progesterone diminished the number of GnRH pituitary binding sites to levels found prior castration. These results indicate that the effects of this 19-nor synthetic progestin upon gonadotropin modulation in the long-term gonadectomized rat do not resemble those of progesterone and suggest that NET is acting through different mechanisms. The data are consistent with an estrogen-like mode of action.

Nuclear translocation of estradiol receptors by the in vivo administration of norethisterone: an alternate mechanism for gonadotropin inhibition

In order to investigate the anti-gonadotropic effect of norethisterone (NET) in long-term ovariectomized rats, we studied the interaction of this synthetic progestin with intracellular steroid receptors in the anterior pituitary by a nuclear exchange assay. The results demonstrated that the administration of NET to long-term ovariectomized rats resulted in nuclear translocation of estradiol cytosol receptors in the pituitary and uterus with a rate of accumulation and nuclear retention being similar in both tissues. Accumulation of nuclear estradiol receptors in the pituitary was in agreement with the rate of LH inhibition in NET-treated rats. The results presented in this communication may explain the anti-gonadotropic activity of NET in long-term ovariectomized rats in addition to its well known progestational activity.

Interaction of medroxyprogesterone acetate with cytosol androgen receptors in the rat hypothalamus and pituitary

The binding of medroxyprogesterone acetate (MPA) with cytosol androgen receptors from rat pituitary and hypothalamus was studied. The pituitary and hypothalamic cytosol androgen receptors from adult castrated female rats were in vitro labeled using 3H natural (testosterone (T) and 5 alpha-dihydrotestosterone (DHT] and [3H]synthetic (methyltrienolone) androgens as radioligands. The [3H]androgen-receptor complexes sedimented with a coefficient of 8S in linear sucrose gradients. When incubated with an excess of radioinert MPA, specific binding was abolished indicating interaction of MPA with androgen receptors. Furthermore specific [3H]MPA-androgen cytosol receptor complexes could be identified in these neuroendocrine tissues when a post-gradient receptor labeling technique was used in the absence or presence of radioinert MPA, DHT, and triamcinolone acetonide. A study of binding kinetics disclosed that the equilibrium dissociation constant and saturation binding capacity for the MPA binder, were similar to those exhibited by DHT binding to androgen receptors in both studied tissues under identical experimental conditions. The overall results were interpreted as demonstrating that MPA interacts with cytosol steroid receptors other than those of progesterone in the rat hypothalamus and anterior pituitary. The data are consistent with MPA binding to androgen receptors.

Hypergonadotrophic hypogonadism in an XX female subject due to 17,20 steroid desmolase deficiency

A 22 year old XX female patient with primary amenorrhoea and sexual infantilism was studied. Persistently elevated serum LH and FSH concentrations and exaggerated LRH pituitary responsiveness indicated deficient ovarian hormonal production. Serum levels of C21 and C19 steroids measured by specific radioimmunoassays before and after appropriate stimulations demonstrated an impairment of adrenal and ovarian steroid biosynthesis. Baseline levels of androstenedione (delta 4-A), testosterone (T), and oestradiol-17 beta (E2) were persistently below the normal range for healthy women at early follicular phase, whereas progesterone (P) and 17 alpha-OH-progesterone (17-OH-P) serum levels were significantly higher than those observed for normal women. Adrenal and gonadal stimulation with ATCH and hCG, respectively, resulted in a considerable rise in serum P and 17-OH-P without any significant change in circulating levels of delta 4-A, T, and E2. These findings were consistent with the diagnosis of 17,20 steroid desmolase deficiency at both adrenal and ovarian levels. This is the first report of a 17,20 desmolase deficiency in an XX individual, and is in line with previous suggestions that familial occurrence of the disorder would fit an autosomal recessive pattern of inheritance.

Effects of synthetic steroid contraceptives on biliary lipid composition of normal Mexican women

The effects of two hormonal contraceptives upon the biliary lipid composition of Mexican women were evaluated in a prospective study. Twenty-one healthy volunteers of reproductive age were allocated into three groups (7 subjects each). Group I served as the experimental control (all subjects were bearing a non-medicated IUD), group II received i.m. norethisterone enanthate (NET-e) 200 mg every two months, and group III received an oral combination of 1-norgestrel 150 micrograms and ethinyl estradiol 30 micrograms. The bile lithogenic index as assessed by the relative proportion of cholesterol to bile acids and lecithin was determined in duodenal bile samples obtained before (baseline), during (4 months), and after (12 months) contraceptive administration. The results indicated that NET-e administration resulted in a slight although significant increase of the lithogenic index while the oral formulation did not. The overall data were interpreted as demonstrating that administration of these steroid contraceptives does not constitute a risk factor in terms of gallstone formation in the population studied. The estrogen-like behavior exhibited by NET-e is discussed.

46,XX gonadal absence: a variant of the XX pure gonadal dysgenesis?

Two unrelated 46,XX individuals with female phenotype and sexual infantilism were studied. Endocrine findings showed anoestrogenism and hypergonadotrophism with a normal pituitary response to LRH. Laparotomy disclosed ovarian absence with normal Mullerian derivatives and no gonadal streaks were found within the true pelvis or inguinal canals. This condition represents the 46,XX counterpart of the 46,XY gonadal absence syndrome. Whether the XX agonadism reported here is a different and distinctive entity or is a variant of the XX pure gonadal dysgenesis syndrome can not be ascertained at present.

Clinical and endocrine spectrum in patients with the 45,X/46,XY karyotype

Cytogenetic and endocrine studies were performed in five unrelated 45,X/46,XY individuals in an attempt to correlate them with their clinical expression and gonadal morphology. A lack of a consistent pattern between cytogenetic findings and phenotype was observed. Endocrine studies revealed a wide spectrum of hypothalamic, pituitary, and gonadal hormone production as assessed by the base line levels of LH, FSH, T, and delta 4-A and their responses to appropriate exogenous stimulation (LH-RH and HCG). An adequate correlation between endocrine findings with gonadal morphology and phenotype could be established; thus demonstrating that patients with this particular chromosome complement have a functional integrity of the gonadotropin hypothalamic pituitary activity modulated accordingly with the gonadal function of each particular case.

Inherited male pseudohermaphroditism due to gonadotrophin unresponsiveness

An inherited form of incomplete male pseudohermaphroditism was studied in two post-pubertal and one pre-pubertal sibling. All patients presented a 46XY karyotype infantile female external genitalia, lack of breast development and sexual hair. Persistently elevated serum levels of gonadotrophins with normal pituitary responsiveness to LRH were found. Serum 17-OH progesterone, androstenedione, and testosterone levels were extremely low before and after gonadal stimulation with hCG. Laparotomy revealed absence of Wolffian and Mullerian derivatives. Testes were small and cryptorchidic. Microscopic and ultrastructural examination revealed seminiferous tubules with absence of spermatogenesis and normal Sertoli cells. The interstitial spaces were mainly occupied by poorly differentiated cells although in the post-pubertal patients there were small and randomly distributed nodules of Leydig cells without crystaloids. Incubation of testicular tissue from one post-pubertal patient with [14C]acetate showed lack of 14C-incorporation into appropriate steroid carriers. These data were interpreted as demonstrating that gonadotrophin resistance was the underlying abnormality of this syndrome, representing the human counter part of the "vet" pseudohermaphroditic rat.

Gonadotropin dynamics in XX males

Hypothalamic-pituitary gonadotropin function was evaluated in two postpubertal XX males. Serum levels of LH and FSH were moderately elevated, and the serum testosterone level was low. A subnormal response by testicular Leydig cells to hCG was observed. The LH and FSH responses to LRH were normal. A significant LH increase was observed after castration. Weekly administration of testosterone enanthate (250 mg) for 10 consecutive weeks caused a reduction (greater than 75%) in gonadotropins and abolishment of the LRH pituitary response. No differences were observed in terms of gonadotropin dynamics compared with other forms of hypergonadotropic hypogonadism. These results indicate that XX males exhibit hypergonadotropic hypogonadism secondary to testicular failure with a preserved androgen responsiveness of the hypothalamic-pituitary unit.

On the mechanism of action of progestins

The effect of two synthetic injectable progestins, norethisterone oenanthate3 (NET-e) and medroxyprogesterone acetate (MPA) upon the hypothalamic pituitary unit was evaluated in post-menopausal women (PMW) and in castrated individuals with androgen un-responsiveness in order to gain insight into their mechanism of gonadotrophin inhibition. Continuous administration of natural progesterone (P4) to PMW by medicated vaginal rings was used as the experimental control. Elevated base line levels of serum immunoreactive gonadotrophins and normal pituitary LRH responses were found in PMW and pseudohermaphrodites. Progesterone did not affect circulating gonadotrophin levels or the pituitary LRH response in PMW.

Administration of MPA 150 mg induced a clear decrease in serum gonadotrophins and a significant decrease in LRH pituitary responsiveness in a post-menopausal woman whereas no effect was observed on serum gonadotrophins and pituitary response to LRH in a patient with androgen unresponsiveness. Administration of NET-e 200 mg resulted in a significant decrease in circulating gonadotrophins in PMW and pseudohermaphrodites, while LRH pituitary sensitivity was diminished in all subjects except one post-menopausal woman.

These results demonstrated that two structurally different synthetic progestins (NET-e and MPA) had a potent gonadotrophin inhibitory activity in PMW while natural progesterone did not, thus indicating a different mode of action. Furthermore their differing effect on individuals with complete androgen unresponsiveness suggested that antigonadotrophic activity of NET-e is mediated by its oestrogenic-progestational effect, while MPA acts through its androgenic potency and therefore requires the presence of androgen receptors.

Induction of ovulation in a true hermaphrodite with male phenotype

Ovulation was induced in a 16-yr-old 46 XX/47 XXY true hermaphrodite with a male phenotype. The presence of testicular tissue was assessed by a normal androgen response to hCG. Administration of FSH and LH for 8 consecutive days, followed by a single dose of hCG, induced a biphasic serum profile of 17 beta-estradiol and progesterone similar to that observed in normal menstrual cycles. In addition, a significant rise in serum testosterone was noticed during the luteal phase. Laparotomy revealed the presence of a uterus, with evidence of endometrial bleeding and absence of a vagina. These results demonstrated that gonadotropins were able to induce follicular maturation, ovulation, and endometrial bleeding in a true hermaphrodite resembling a normal ovulatory cycle. Gonadotropin administration can be used as a diagnostic tool for establishing the presence of ovarian tissue in this gonadal development abnormality.

The role of oestrogens on gonadotrophin secretion in the testicular feminization syndrome

The role of oestrogens on gonadotrophin secretion was assessed in three related patients with the complete form of testicular feminization syndrome. Serum LH and FSH levels were measured before and after LRH stimulation as well as before, during and after chronic clomiphene citrate administration. Moderately elevated LH basal levels with a significant LH rise following LRH were observed. Normal or even low FSH level with poor response to LRH were found in all subjects. Administration of clomiphene citrate resulted in a significant serum LH increase without any change of FSH. Following castration both LH and FSH rose and a normal response to LRH was observed. These results were interpreted as demonstrating that, while endogenous oestrogens modulate LH secretion in patients with androgen unresponsiveness, it plays no role in regulating FSH secretion and suggested that a factor of testicular origin without androgenic or oestrogenic activity is responsible for FSH regulation.

Endocrine studies and successful treatment in a patient with true hermaphroditism

A 12-year old, 46 XX true hermaphrodite born with genital ambiguity was studied and successfully treated. The serum LH and FSH profile resembled that of a pubertal normal individual, and LH-RH administration induced a normal LH response. Baseline testosterone serum levels were within the range for normal children. Exogenous HCG stimulation induced a significant serum testosterone increase up to values similar to those observed in normal post-pubertal males. Surgical examination disclosed the presence of bilateral ovotestis, normal Mullerian derivatives, epididymis, and vas deferens. A complete ovotestis with testicular predominance and the testicular portion of the contralateral ovotestis as well as the Wolffian derivatives, were removed. A further HCG stimulation 3 months after surgery, failed to induce serum testosterone increase. Spontaneous menarche was observed 6 months after surgery and ovulation was well documented. At present the patient has several characteristics of female sex including those of chromosome complement, gonad, internal and external genitalia, hormone levels and gender identity, thus demonstrating that treatment was successful and that reproductive function could be obtained. The finding of spontaneous ovulation following removal of the testicular portion suggests normal cyclic gonadotrophic release implying a difference between animal models and man in regard to hypothalamic virilization.

Cytogenetic and endocrine studies in a 45,X female subject with spontaneous sexual development

Cytogenetic and endocrine evaluation of a postpubertal 45,X female subject with Turner's stigmas and spontaneous sexual development was performed. A 45,X chromosomal complement was found in the peripheral blood lymphocytes, bone marrow, and fibroblasts derived from skin and ovaries. Menarche, pubarche, and thelarche occurred at age 12; at age 16 she developed menstrual irregularities, with endometrial bleeding occurring every 60 to 90 days. The ovaries were normal in size, and histologic examination revealed a marked paucity of primordial follicles, increased collagenization, and absence of corpora albicans. Anovulatory cycles with moderately elevated levels of luteinizing hormone (LH) and low follicle-stimulating hormone (FSH) levels were observed. LH-releasing hormone pituitary stimulation induced a normal LH release with a very slight FSH increase. Administration of clomiphene citrate successfully induced a normal-length ovulatory cycle. Similarities in the hormonal situation of this patient and that seen in the Stein-Leventhal syndrome are pointed out.

Anorchia and persistent Müllerian duct: a variant of the embryonic testicular regression syndrome

A 20-yr-old phenotypical male with a 46, XY chromosome complement, a hernia uteri inguinale, and bilateral anorchia was studied. Eunochoidal body proportions, infantile type of male external genitalia with empty scrotum, underdeveloped sexual characteristics, and delayed bone age suggested the existence of inadequate testicular function. Extremely low levels of circulating testosterone and a lack of response to hCG stimulation was found. Persistently elevated blood levels of LH and FSH with an adequate pituitary response to an iv bolus of synthetic LRH was demonstrated, thus indicating inadequate endocrine gonadal function as well as functional integrity of the hypothalamic-pituitary unit. At the time of an inguinal hernioplasty, a small but well developed uterus was removed. No gonads were found within the true pelvis, inguinal canals, or along the anatomical pathways of testicular descent. A cord-like structure found in the left inguinal canal contained only fibrous tissue without gonadal elements. It is proposed that the occurrence of two altered events during embryogenesis, failure of Müllerian duct regression and late testicular regression, may explain the underlying defect in this unusual abnormality of sexual differentiation.

Gynecomastia as a familial incomplete male pseudohermaphroditism type 1: a limited androgen resistance syndrome

Four postpubertal 46 XY male patients with an inherited form of bilateral gynecomastia were studied to delineate the nature of the disease. Normal serum FSH and moderately elevated serum LH with concomitantly increased circulating levels of testosterone (T) and estradiol (E2) were found persistently in all cases in blood samples drawn at frequent intervals. LRH pituitary stimulation resulted in an exaggerated LH response and a normal FSH response. Chronic administration of T-cyclopentylate failed to decrease serum LH levels. The peripheral conversion rate of androstenedione to estrone was within normal limits. All patients had low ejaculate volumes with relatively normal spermatozoa counts. Testicular biopsies revealed normal Leydig cells and complete spermatogenesis. Urological examination disclosed that the prostate gland was extremely small. The breast tissue demonstrated the presence of tubular structures as well as the specific binding of [3H]T and [3H]dihydrotestosterone (DHT), which was inhibited by nonlabeled T, DHT, E2, and progesterone, but not by cortisol. The pedigree suggested a recessive X-linked inherited trait. A patient with a nonfamilial form of gynecomastia served as a control in all studies. These data were interpreted as demonstrating that this inherited type of gynecomastia represents the mildest expression of the androgen resistance syndromes and, therefore, belongs to the type 1 form of familial incomplete male pseudohermaphroditism.

Inherited congenital normofunctional testicular hyperplasia and mental deficiency. A corroborative study

Three 46,XY unrelated individuals out of 84 postpubertal male inpatients with severe mental deficiency in a psychiatric hospital were found to have megalorchidia and macrogenitosomia. One of the cases had a similarly affected brother. Endocrine studies were performed in two of the cases with similar results. Normal plasma levels of pituitary gonadotropins were found. A normal testicular function was demonstrated by the finding of normal: (a) baseline plasma testosterone levels and a significant rise following human chorionic gonadotropin administration, (b) sperm analysis, and (c) morphology and cell architecture of the testes. These results were compatible with normofunctional testicular hyperplasia confirming previous observations and allowing the definite individualization of a syndrome with mental deficiency probably due to an X-linked recessive mutation.

Suprahypophyseal dysfunction in a patient with asexual ateleiosis

The neuroendocrine function of a 19 years old female dwarf with primary amenorrhoea and lack of sexual development (asexual ateleiosis) was studied. Undetectable fasting plasma levels of growth hormone (GH) and a lack of response to three different provocative stimuli was observed. Oestrogen administratin did not modify the GH response. Thyroid and adrenal function were within normal limits. Undetectable plasma levels of immunoreactive oestradiol and lack of oestrogenic activity in vaginal smears indicated absence of ovarian function. Low levels of circulating gonadotrophins with a significant rise after synthetic LH-RH administration was demonstrated, while clomiphene citrate failed to induce ovulation. Following 6 months of continuous GH administration a significant increase in the growth rate was evident, whereas no pubertal development was observed. These data are interpreted as demonstrating the suprahypophyseal origin of the sexual infantilism in a patient with inappropriate GH secretion. It is suggested that a combined deficiency of LH-RH and GH-RH may account for the aetiology of this disorder.

In vitro conversion of 5-androstenediol to testosterone by the central nervous system and pituitary of the male rat

The in vitro metabolism of 7-3H-5-androstenediol by the pituitary, some brain structures, and ventral prostate of adult castrated male rat was studied. Conversion of 5-androstenediol to radiochemically pure testosterone was demonstrated in all tissues studied in the presence of a NADPH generating system. Formation of dihydrotestosterone and dehydroepiandrosterone was also detected. The higher conversion rates were found in the pituitary, hypothalamus and mesencephalic tegmentum. These results demonstrate the presence of 3beta-hydroxy steroid oxidoreductase, delta4- delta5 isomerase, 5alpha-reductase, and 17beta-ol dehydrogenase in the rat brain which may in part explain the behavioral and brain virilization effects of 5-androstenediol.

Pituitary and gonadal function in patients with the Laurence-Moon-Biedl syndrome

Pituitary and gonadal functions were evaluated in two pre-pubertal male siblings and in one unrelated adult male with the complete form of the Laurence-Moon-Biedl syndrome. The adult patient (19 years old) presented lack of secondary sex characteristics, azoospermia, and sub-normal external genitalia development. Testicular biopsy showed an arrest of spermatogenesis and diminished number of Leydig cells. Low plasma testosterone levels and normal responsiveness to HCG administration were found. A significant rise of pituitary gonadotrophin after LH-RH stimulation and a lack of response to clomiphene citrate was demonstrated. The pre-pubertal siblings (9 and 11 years old) had genital hypoplasia and undetectable plasma levels of testosterone, though there was a significant rise after HCG stimulation. Plasma gonadotrophin levels were within the assay sensitivity limits and a normal pituitary responsiveness following LH-RH stimulus was noted. Slightly low excretion of urinary 17-OH-corticosteroids which increased significantly after ACTH and metyrapone was demonstrated in both patients. Elevated levels of serum lipoproteins and triglycerides were found in all cases. These results are interpreted as demonstrating the suprahypophyseal origin of the dysfunction thus producing hypogonadism observed in the adult patient, and suggesting that a similar dysfunction might account for the genital hypoplasia in the pre-pubertal boys with this inherited disorder.

Inherited congenital normofunctional testicular hyperplasia and mental deficiency

Four 46,XY siblings with congenital bilateral megalorchidia, marcogenitosomia, and severe mental deficiency were investigated. The testicular size was significantly larger than age-matched normal males. A normal hypothalamic-pituitary gonadotropin function was demonstrated by the finding of normal levels of luteinizing and follicle-stimulating hormones in blood samples drawn at frequent intervals and by normal responses to gonadotropin-releasing hormone and testosterone administration. A normal testicular function was shown by the finding of normal (a) plasma testosterone and estradiol levels, (b) gonadal response to human chorionic gonadotropin, (c) sperm analysis, and (d) morphology and cell architecture of the testes. Adrenal function was found to be within normal limits. These results demonstrated the existence of normofunctional testicular hyperplasia. The family studies suggested that this distinct congenital disorders is inherited as an X-linked recessive trait.

Pseudohermaphroditism due to XY gonadal absence syndrome

A 21-year-old phenotypic female with a 46,XY chromosome complement and gonadal absence was studied. Basal levels of plasma immunoreactive luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone, and oestradiol were measured. Pituitary sensitivity and reserve was evaluated by the exogenous administration of synthetic luteinizing hormone-releasing hormone. The episodic release of gonadotrophins was assessed by measuring plasma LH and FSH in plasma samples obtained at 20-minute intervals for a 4-hour period. Endocrine gonadal function was evaluated by a stimulation test with human chorionic gonadotrophin for 3 days. The results showed: a) persistently raised plasma levels of both LH and FSH; b) a pulsatile pattern of release of both gonadotrophins and a normal pituitary response to the synthetic hypothalamic decapeptide; and c) extremely low levels of circulating testosterone and oestradiol with a lack of response to the HCG stimulus. A careful exploratory laparotomy revealed absence of uterus, Fallopian tubes, the Mullerian portion of the vagina, and gonads. No Wolffian derivatives were found. A dissociation of testosterone and the so-called Jost substance effects during early sexual development may explain the findings in this unusual abnormality. The term 'XY gonadal absence syndrome' including five types of variants to designate this condition is proposed.

Pituitary LH and FSH secretion and responsiveness in women of old age

The plasma concentrations and episodic fluctuations of immunoreactive FSH and LH as well as the pituitary sensitivity to LH-RH stimulation were evaluated in post-menopausal women. The subjects were divided into 4 groups according to age. Group 1: 60-70 years old (n = 11), group 2: 70-80 years old (n = 22), group 3: 80-90 years old (n = 31) and group 4: 90-100 years old (n = 8). Standards used in gonadotrophin radioimmuno-assays included the LER-907 preparation and a pooled post-menopausal serum. Since it was found that circulating gonadotrophins have an immunological pattern different from that shown by the pituitary preparation, the results were expressed in mIU/ml calculated accordingly to the immunological behavior of pooled post-menopausal sera. The mean (+/- SE) plasma levels of FSH (mIU/ml) were: group ): 105 +/- 9.5, group 2: 149.3 +/- 10.5, group 3: 124.8 +/- 7.1 and group 4: 149.4 +/- 25.3. The mean (+/- SE) plasma levels of LH (mIU/ml) were: group 1: 81.9 +/- 12.5, group 2: 95.4 +/- 9.9, group 3: 84.3 +/- 7.7 and group 4: 113.5 +/- 19.1. No statistically significant differences were observed among the 4 groups. One patient from each group was randomly selected in order to evaluate their LH and FSH episodic release as well as their pituitary responsiveness to exogenous stimulation. A pulsatile plasma pattern of gonadotrophin and a normal pituitary response to LH-RH injection were observed in the 4 patients studied. The results are interpreted as demonstrating that normal pituitary gonadotrophin function and pituitary reserve and responsiveness to exogenous stimulation are maintained in women of advanced age.

The Stein-Leventhal syndrome: a neuropituitary disorder

Hypothalamic and pituitary gonadotropin function and responsiveness in four patients with well-documented Stein-Leventhal syndrome were studied. All patients were of reproductive age and had had menstrual disorders since menarche. Estrogen production was assessed by measuring the circulating levels of immunoreactive estradiol, by vaginal smears, and by the progestogen-induced menses test. Gonadotropin function was evaluated by measuring the serum levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in blood samples obtained at 15-minute intervals for 150 minutes. Pituitary gonadotropin reserve and responsiveness were studied by giving an intravenous bolus of synthetic LH-releasing hormone (LH-RH) and measuring the circulating gonadotropin levels before and after the injection.