Showing papers on "Testosterone published in 1975"
TL;DR: The results suggest that not only testosterone but also other, not yet identified, androgens may be involved in the masculinzation of the brain.
Abstract: Radioimmunological determination of serum LH, FSH, and estradiol concentrations in prepubertal female rats demonstrates the temporal coincidence of increased serum levels of these hormones between days 9 and 21. Serum FSH and estradiol levels are continuously high during that time, whereas interindividual fluctuations in LH levels were enormous. No high LH, FSH, and estradiol levels were observed between day 21 and puberty, during which time serum prolactin and progesterone gradually increased. Serum testosterone in the female immature rats stayed uniformly low. It is suggested that increased serum estradiol levels in the presence of low prolactin levels (between day 10 and 20) act in a positive feedback fashion on the CNS-pituitary axis. The resulting increased gonadotropin levels are later (between day 20 and puberty) decreased by an inhibitory action of prolactin and/or progesterone on pituitary gonadotropin release. In male rats serum FSH and prolactin, which were low during the first 3 weeks, increased later to reach high levels during puberty. Serum LH was slightly elevated during the 2nd and 3rd week of life at which time serum progesterone also increased to reach the highest levels in the prepubertal period. Serum testosterone was higher in male than in female rats for the first 3 weeks of life; the difference between both sexes was significant but not striking. Between day 21 and the prepubertal period the testosterone levels were relatively low, but they increased again during puberty. Sex differences in androgen levels (measured with a less specific antibody) were more pronounced whereas estradiol levels in males showed the same pattern between birth and puberty as in the female littermates. These results suggest that not only testosterone but also other, not yet identified, androgens may be involved in the masculinzation of the brain.
724 citations
TL;DR: In this paper, different aspects of steroid hormone receptors are discussed, and the kinetic parameters of the binding reaction of the uterine receptor-estradiol are also studied, and it is found that when estradiol, estrone, and estriol are compared, the rate of dissociation of receptor steroid complexes is similar for the three steroids.
Abstract: Publisher Summary This chapter discusses different aspects of steroid hormone receptors. Steroid hormones show different kinds of activities when examined at the physiological level. Differences may be also classified in terms of gross biological responses. Studies of the development of male secondary sex organs and hypothalamus in mammals, and of the oviduct in avians and batracians suggest that hormones such as estradiol or testosterone can promote the formation of morphologically and functionally stabilized new type of cells, enough to justify thinking in terms of differentiation processes. There are intracellular specific protein receptors for binding steroid hormones, all properties of which are compatible with the assumption that they are receptors. It is found that when estradiol, estrone, and estriol are compared, the rate of dissociation of uterine receptor steroid complexes is similar for the three steroids, but the rate of association is slower for the two lower affinity ones than for estradiol. The kinetic parameters of the binding reaction of the uterine receptor-estradiol are also studied.
333 citations
TL;DR: It is concluded that FSH regulates estrogen biosynthesis in granulosa cells of hypophysectomized rats by a specific stimulation of the aromatizing enzyme system.
Abstract: Granulosa cells isolated from the ovaries of hypophysectomized immature rats synthesize and secrete estradiol-17² and estrone when grown for 2 days in monolayer culture in a synthetic medium containing testosterone (0.5 μM) and a highly purified folliclestimulating hormone (FSH) preparation (0.25 μg/ml). Secretion is negligible in the absence of either testosterone or FSH, and a highly purified luteinizing hormone (LH) preparation (0.25 μg/ml) was without significant stimulatory effect. It is concluded that FSH regulates estrogen biosynthesis in granulosa cells of hypophysectomized rats by a specific stimulation of the aromatizing enzyme system.
324 citations
TL;DR: These studies provide direct demonstration of estradiol-17beta production by Seroli cells from normal animals, and offer evidence that the synthesis of this steroid is regulated at the level of the aromatizing enzyme system by FSH and adenosine 3':5' cyclic monophosphate.
Abstract: Sertoli cells isolated from testes of 20-day-old rats and maintained in primary culture synthesized estradiol-17beta [1,3,5(10)-estratriene-3,17beta-diol] (measured by specific radioimmunoassay) when testosterone (17beta-hydroxy-4-androsten-3-one) 0.5 muM, was added to the culture medium. No detectable estradiol synthesis occurred when cells were incubated in medium containing pregnenolone (3beta-hydroxypregn-5-en-20-one), 0.5 muM, or containing no added steroid substrate. Follicle-stimulating hormone (FSH) (NIH-FSH-S10, 5 mug/ml) stimulated estradiol synthesis 12- to 80-fold when added to medium containing testosterone, but not when added to medium containing pregnenolone or no exogenous steroid substrate. A highly purified FSH preparation, with FSH potency 50 times that of the NIH-FSH, caused a similar stimulation at a concentration of 0.25 mug/ml of medium, whereas luteinizing hormone (NIH-LH-S18, 5 MUG/ML) Caused only marginal stimulation. Dibutyryl-adenosine 3':5' cyclic monophosphate, 0.1 mM, caused a 30-fold increase in estradiol synthesis by Sertoli cells cultured in medium containing testosterone. These studies provide direct demonstration of estradiol-17beta production by Seroli cells from normal animals, and offer evidence that the synthesis of this steroid is regulated at the level of the aromatizing enzyme system by FSH and adenosine 3':5' cyclic monophosphate.
263 citations
TL;DR: 15% of the circulating testosterone is not secreted but is derived by peripheral conversion from androstenedione, which means that the increased estradiol levels in cirrhosis result, in large part, from increased peripheral Conversion from the androgens.
Abstract: The contribution, by peripheral conversion, of androstenedione and testosterone to the circulating estrogens was determined in men with cirrhosis of the liver. The conversion ratio of androstenedione to estrone, estradiol and testosterone and the conversion ratio of testosterone to estrone (but not estradiol) and androstenedione were significantly increased. The plasma concentrations of androstenedione and testosterone were increased and decreased respectively; the mean plasma concentration of androstenedione being similar to that found in normal women. The metabolic clearance rate of androstenedione was not altered in cirrhosis although the metabolic clearance rate of testosterone was decreased. The production rate of androstenedione was elevated while that of testosterone was reduced. The instantaneous contribution of plasma androstenedione to estrone and estradiol was increased in cirrhosis as was the contribution of testosterone to estrone (but not to estradiol). Thus the increased estradiol levels in cirrhosis result, in large part, from increased peripheral conversion from the androgens. The percent contribution of plasma testosterone to plasma androstenedione was decreased although the absolute amount derived by conversion was normal. The percent contribution of plasma androstenedione to plasma testosterone was increased sevenfold in cirrhosis. The fraction of the daily androstenedione production derived from the plasma testosterone pool was not significantly altered. However, a significant fraction of the daily production rate of testosterone was derived from androstenedione. Thus, 15% of the circulating testosterone is not secreted but is derived by peripheral conversion from androstenedione. Normal levels of gonadotropins were found in cirrhosis.
247 citations
TL;DR: The glycosidase-treated hormone derivatives were potent inhibitors of hCG-induced cyclic AMP accumulation, suggesting that removal of the sugars did not influence binding of the hormone to the cell as much as it reduced the ability of the bound hormone to activate adenyl cyclase.
245 citations
TL;DR: A parallel rise in LH and testosterone levels occurred from Days 30 to sexual maturity and corresponded to the development of the adult generation of intestitial cells and an LH peak and a nadir of testosterone levels was observed between Days 6 and 14 at time corresponding to regression of the fetal generation of interstitial cells.
Abstract: Serum LH, FSH and testosterone concentrations were measured by radioimmunoassays in male Sprague-Dawley rats from birth to 80 days of age. The levels of FSH were significantly elevated during the first 5 days of postnatal life. An abrupt decline in FSH concentrations occurred during this period, from levels of 800 ng/ml on day 1 to levels of 300 ng/ml on Day 6. Subsequently, FSH levels fluctuated widely until about Days 30 to 45, when a secondary peak of FSH was observed. Thereafter, a decline in FSH levels to those found in adult rats occurred. This decline in FSH levels appears to coincide with the first release of mature spermatozoa from the germinal epithelium in the testis. During the first 30 days of postnatal life, LH and testosterone values appeared to be inversely related to each other and an LH peak and a nadir of testosterone levels was observed between Days 6 and 14 at time corresponding to regression of the fetal generation of interstitial cells. A parallel rise in LH and testosterone levels occurred from Days 30 to sexual maturity and corresponded to the development of the adult generation of intestitial cells.
215 citations
TL;DR: In this article, an animal model was developed to examine perturbation in gonadal function that occurs in man as a consequence of chronic ethanol ingestion and confirms previous data which suggest that ethanol is a primary testicular toxin.
210 citations
TL;DR: Japanese quail eggs either were injected with testosterone propionate (TP), estradiol benzoate (EB), or oil, or were not injected, but either androgen or estrogen administered before hatching demasculinized males, but did not masculinize females or defeminize either sex.
Abstract: On the 10th day of incubation, Japanese quail eggs either were injected with testosterone propionate (TP), estradiol benzoate (EB), or oil, or were not injected. When sexually mature, all birds were examined for a variety of sexually dimorphic behavioral and physical characteristics, both masculine and feminine. They were then exposed to a short photoperiod (causing gonadal regression), treated with either TP or EB, and examined again. Either androgen or estrogen administered before hatching demasculinized males, but did not masculinize females or defeminize either sex. In contrast, early sex hormones masculinize and/or or defeminize mammals. This difference is discussed in relation to other differences in avian and mammalian sexuality.
206 citations
TL;DR: It is concluded that aromatization is an unnecessary prerequisite for the action of androgens on the hypothalamic-pituitary axis.
Abstract: A variety of studies in man and animals demonstrate that testosterone (T) is aromatized to estradiol (E) in the hypothalamus and limbic system. These observations suggested the possibility that conversion to E is an absolute requirement for the biologic activity of T on the hypothalamic-pituitary axis. Since this hypothesis implies a common mechanism of action of these two steroids, the demonstration of divergent effects of T and E on luteinizing hormone (LH) secretion would exclude this possibility. To test this hypothesis, the actions of T and E on three separate aspects of LH release (mean LH, pulsatile LH secretion, and responsiveness to LH-releasing hormone [LH-RH]) were contrasted. T and E, infused at two times their respective production rates into normal men, reduced mean LH levels similarly during 6 h of steroid infusion and for 6 h thereafter. However, these steroids exerted different effects on pulsatile secretion. E reduced the amplitude of spontaneous LH pulse from pre- and postinfusion control levels of 75+/-14 and 68+/-5.6% (SEM) to 39+/-5.7%. In contrast, T increased pulse amplited to 96+/-14% and decreased pulse frequency from basal levels of 3.4+/-0.31 to 1.8+/-0.31 pulses/6h. The site of suppressive action was determined by administering 25 microgms of LH-RH to the same men during T and E infusions and during three additional control periods without steroid administration. LH-RH produced similar 170-190% increments in serum LH during the three control periods and during T infusion. In contrast, E markedly blunted (76+/-31%, p less than 0.005) the LH response to LH-RH. Under the conditions of acute steroid infusion at doses (utilized in these experiments) producing similar inhibition of mean LH, E but not T acted directly on the pituitary to diminish LH-RH responsiveness. As further support that androgens can act without conversion to estrogens, the effects of a nonaromatizable androgen, dihydrotestosterone (DHT), on mean LH levels were studied. DHT, infused at the same rate as T, suppressed mean LH to a similar but somewhat greater extent than T. Since T and E produced divergent effects on LH secretion and a nonaromatizable androgen, DHT, suppressed mean LH, aromatization is not a necessary prerequisite for the action of androgens on the hypothalamic-pituitary axis.
201 citations
Journal Article•
TL;DR: In male pseudohermaphrodites born with ambiguity of the external genitalia but with marked virilization at puberty, biochemical evaluation reveals a marked decrease in plasma dihydrotestosterone secondary to a decrease in steroid 5alpha-reductase activity.
TL;DR: It is postulated that a defect in that portion of the hypothalamus involved in the receipt and/or interpretation of message might be at fault in uremia.
TL;DR: The presence of testosterone in neonatal life plays a role in the masculinisation of open-field behavior and that its effect is partly mediated by the presence of cyclic ovarian secretions in the adult female rat and their absence in the male and TP treated female.
TL;DR: A striking increase of both testosterone and androstenedione levels was noted after administration of testosterone undecanoate, which is otherwise only achieved by parenteral testosterone application, and promises to be an effective medication for oral androgen replacement.
Abstract: Plasma testosterone and androstenedione levels in men were measured after oral administration of free testosterone and testosterone undecanoate. Both androgens were determined by simultaneous, specific radioimmunoassays after separation and isolation by thin layer chromatography. While free unesterified testosterone had no effect on plasma androgen levels, a striking increase of both testosterone and androstenedione levels was noted after administration of testosterone undecanoate, which is otherwise only achieved by parenteral testosterone application. This effect of testosterone undecanoate is probably due to absorption via the lymph rather than via the portal vessels so that peripheral circulation is reached before metabolism in the liver. Testosterone undecanoate promises to be an effective medication for oral androgen replacement.
TL;DR: Propylene glycol (glycol) solutions containing either testosterone (T) or estradiol (E2) were infused directly into the preoptic area (POA) of longterm castrated rats in order to reinstate male copulatory behavior.
Abstract: Propylene glycol (glycol) solutions containing either testosterone (T) or estradiol (E2) were infused directly into the preoptic area (POA) of longterm castrated rats in order to reinstate male copulatory behavior. In addition, castrated males were administered T or E2 in the POA in combination with a steroid that has been shown to block the aromatization of testosterone to estradiol, androstl, 4,6-triene-3,17-dione (ATD). The facilitatory action of testosterone on mounting behavior was blocked when it was given in combination with ATD. Animals treated in the POA with glycol † T, glycol † E2, or ATD 4- E2 all showed significant increases in mounting behavior over preimplant levels. There was no significant rise in the number of intromissions or ejaculations in any of the treatment groups. These results support the hypothesis that, at least for mounting behavior, aromatization is necessary for the stimulation of male sexual behavior by testosterone. (Endocrinology 97: 1545, 1975)
TL;DR: It is suggested that plasma hormones rise in anticipation of mating, although not to the same extent as following mating, and that the anticipatory rise may function to initiate or facilitate mating behavior.
TL;DR: Plasma testosterone levels and 24-hr urinary excretions of unconjugated testosterone of adult homosexual men were found to be in the normal range as observed in heterosexual men, suggesting that homosexual men possess a predominantly female-differentiated brain which may be activated to homosexual behavior by normal or approximately normal androgen levels in adulthood.
Abstract: In male rats, androgen deficiency during a critical hypothalamic organizational period was shown to give rise to a predominantly female-differentiated brain, homosexual behavior, and demonstration of a positive estrogen feedback effect. A positive estrogen feedback effect was also induced in intact homosexual men in contrast to intact heterosexual and bisexual men. Thus in 21 homosexual men an intravenous injection of 20 mg Presomen (Premarin) produced a significant decrease of serum LH levels followed by an increase above initial LH values. In 20 heterosexual and in five bisexual men, by contrast, intravenous estrogen administration, while producing a significant decrease of the serum LH level, was not followed by an increase above the initial LH values. Using a radioimmunoassay, plasma testosterone levels and 24-hr urinary excretions of unconjugated testosterone of adult homosexual men were found to be in the normal range as observed in heterosexual men. This finding suggests that homosexual men possess a predominantly female-differentiated brain which may be activated to homosexual behavior by normal or approximately normal androgen levels in adulthood.
TL;DR: The results show that spermatocytes and Sertoli cells have the capacity to metabolise [14C]testosterone to 5α-reduced prodr ucts; dihydrotesterone is the major product formed by sperMatocytes, whereas in SERToli cells further metabolism to 5 α-androstane-3α, 17β-diol occurs.
Abstract: Seminiferous tubules isolated from normal adult rats converted (14C) testosterone to (14C) androstanediol and (14C) androstenedione as the major metabolites; (14C) dihydrotestosterone and (14C) androsterone were produced in lesser amounts. Tubules from immature rats (26-28 days of age) converted a higher proportion of (14C) testosterone to 5alpha-reduced products than did tubules from adult rats. Spermatocyte-enriched preparations contain 5alpha-reductase. The lower level of 5alpha-reductase activity in spermatid-spermatocyte preparations indicates that this enzyme is low or absent in spermatids. Sertoli cell-enriched preparations contain 5 alpha-reductase and a high level of 3alpha-hydroxysteroid dehydrogenase. The results show that spermatocytes and Sertoli cells have the capacity to metabolise (14C) testosterone to 5alpha-reduced products; dihydrotesterone is the major product formed by spermatocytes, whereas in Sertoli cells further metabolism to 5alpha-androstane-3alpha, 17beta-diol occurs.
TL;DR: This first report of an effect of testosterone on isolated muscle cells, coupled with the recent description of a receptor for anabolic steroids in muscle cytoplasm, indicates that the effects of male sex hormones result from a direct interaction with muscle rather than from a primary interaction with some other tissue.
Abstract: A direct effect of physiological levels of testosterone on skeletal muscle cells in tissue culture is reported. The effect is a 25% stimulation of labeling index by radioautographic analysis of cultures following incubation with [3H]thymidine at the end of a 48-h exposure to 10(-8)M testosterone in 2% gelding serum. This stimulation was observed in primary myoblasts, an established myogenic cell line (Yaffe's L6 cells), and muscle fibroblasts. The effect was specific for testosterone: the labeling index did not change significantly from control values when estradiol, 5beta-pregnanediol, androstenedione, or dihydrotestosterone were added, although small increases were noted in the latter two cases. The effect on the labeling index was localized as a decrease in time spent in the G1 phase of the cell cycle, which decreased about 30% in muscle cells exposed to testosterone. This first report of an effect of testosterone on isolated muscle cells, coupled with the recent description of a receptor for anabolic steroids in muscle cytoplasm, indicates that the effects of male sex hormones result from a direct interaction with muscle rather than from a primary interaction with some other tissue.
TL;DR: The data suggest a deficiency of hypothalamic hypophysiotropic hormones rather than a primary pituitary defect in male infants with normal birth weight and length and without gross central nervous system malformations, which is critical for prompt treatment of the life-threatening cortisol deficiency.
TL;DR: It is infer that the increased NGF concentration in male submaxillary glands is due to a 10‐fold increase in the rate constant of synthesis, similar to that seen in female glands after testosterone treatment.
Abstract: —It has long been known that the activity of nerve growth factor (NGF) in extracts obtained from the male mouse submaxillary gland is higher than in extracts from the female gland, and that the activity present in female glands can be increased by testosterone treatment. This communication presents a study of the mechanism of the testosterone effect. Of several different steroids administered to female Swiss–Webster mice only testosterone propionate led to increased gland NGF activity. The increase did not appear to be due to an enhancement of the activity of pre-existing molecules on sympathetic nerve fiber outgrowth, or due to an altered affinity for the specific antibodies used in the estimation of NGF content, but appeared rather to be due to an accumulation of NFG molecules. The kinetics of change in the male gland NGF content upon castration and secondary testosterone propionate stimulation was analyzed by application of the plateau principle. The rate of loss of NGF from this organ was not measureably different between the castrate and testosterone propionate stimulated state. On the other hand, there was estimated to be a 10-fold difference in the rate of input between the basal and steroid stimulated state. Tracer amounts of radioiodine labelled NGF administered i.v. was not accumulated by the gland, and there is no evidence for uptake of this protein from the circulation. We, therefore, infer that the increased NGF concentration in male submaxillary glands is due to a 10-fold increase in the rate constant of synthesis.
TL;DR: Fibroblasts grown from the foreskin of two patients with familial incomplete male pseudohermaphroditism, type 2, an autosomal recessive disorder of phenotypic sexual differentiation, showed a marked deficiency in the capacity to form dihydrotestosterone, while fibroblast monolayers grown from skin biopsies of foreskin, scrotum, and various nongential skins formed dihydotestosterone at a normal rate.
TL;DR: Elevated GH levels support elevated GH as secondary to starvation of anorexia nervosa and not an independent hypothalamic-pituitary disturbance, and endocrine findings indicate hypothalamic and pituitary malfunction is not confined to GH.
Abstract: We studied nine patients with anorexia nervosa: five were "undernourished" and four were "well-nourished." The undernourished patients had significantly higher plasma growth hormone (GH) levels in a fasting state and higher GH rebounds following glucose administration. In four of these patients, GH levels decreased to normal after weight restoration. Decreased urinary follicle stimulating hormone (FSH) in three and plasma luteinizing hormone in six patients were not related to nutritional status; however, positive correlation was found between duration of illness and urinary FSH. Other results included decreased plasma testosterone in the one male, elevated plasma cortisol in five, and decreased 17-ketosteroid excretion in five patients. The results support elevated GH as secondary to starvation of anorexia nervosa and not an independent hypothalamic-pituitary disturbance. Other endocrine findings indicate hypothalamic-pituitary malfunction is not confined to GH.
TL;DR: There was a change in the predominance of individual 16-androstenes in the testis during development, which closely paralleled the sequence for the biosynthesis of these compounds proposed from previous studies in vitro.
Abstract: After extraction from the testes of boars of different ages, C19 steroids including 16-androstenes were determined by gas-liquid chromatography. Similarly, 16-androstenes were determined in the submaxillary glands of these boars. A high concentration of testosterone was found in the testes of 84-day-old fetuses, and this might be significant in the differentiation of male behaviour. The amount of testosterone exceeded that of androstenedione during postnatal development, and dehydroepiandrosterone and 5-androstenediol as free and sulphates were found in high concentrations particularly in postpubertal boars, suggesting that the 5-ene pathway for the synthesis of testosterone might be important. There was a change in the predominance of individual 16-androstenes in the testis during development, which closely paralleled the sequence for the biosynthesis of these compounds proposed from previous studies in vitro. Whereas the amount of 5alpha-androst-16-en-3beta-ol exceeded that of 5alpha-androst-16-en-3alpha-ol in post-pubertal testes, 5alpha-androst-16-en-3alpha-ol was predominant in the submaxillary glands at all ages. The high concentration of 16-androstenes found in the mature boar, are discussed in relation to their release as pheromones and as factors responsible for taint in boar meat.
TL;DR: The data provide partial support for the major hypotheses that neonatal gonadectomy and opposite sex hormones administered to male and female castrated rats would reverse the normal sex-associated abilities of the white rate and supported the hypothesis that sex hormones in adults would be mainly activational and have less marked effects than the significant directional changes obtained by these neonatal sex hormones and castration techniques.
TL;DR: It is believed that the classical concept of androgen action must be enlarged to encompass central effects that require the aromatization of androgens as well as those requiring ring A reduction.
TL;DR: The metabolism of 7alpha-3H-dehydroepiandrosterone was studied in six human breast carcinomas in vitro and Observations on the relationship of androgen metabolism and hormone dependency are discussed.
TL;DR: Although no statistically significant relationships were found between the hormonal and clinical abnormalities of Klinefelter's syndrome it is probable that the hyperoestrogenism and androgen deficiency are linked to the development of the signs of feminization and hypogonadism.
Abstract: Some aspects of the hormonal abnormalities of Klinefelter's syndrome have been studied in nineteen patients. As a group the plasma production rate, the total and free levels of testosterone, and the metabolic clearance rates of testosterone and oestradiol were low. Plasma oestradiol, LH and FSH levels were elevated and there was increased peripheral conversion of testosterone to oestradiol. The production rates of oestradiol and the binding capacities of the sex steroid binding globulin were normal. There were fluctuations in the blood levels of LH, FSH, testosterone and oestradiol, but these appeared to be less marked than in healthy men. Both LH and FSH levels were suppressed by acute or prolonged testosterone administration and there was no evidence for a differential effect on LH. It is suggested that the threshold for suppression of LH and FSH is increased in hypergonadotrophic states. Although no statistically significant relationships were found between the hormonal and clinical abnormalities of the syndrome it is probable that the hyperoestrogenism and androgen deficiency are linked to the development of the signs of feminization and hypogonadism.
TL;DR: Reduced androgen binding with Tfm/Y mutants and blocking experiments with non-radioactive estradiol and testosterone indicate the existence of at least two binding components: one with high affinity only for est radiol, the other with affinity for both androgens and estrogen.
Abstract: Androgen- and estrogen-binding macromolecules from the hypothalamus plus preoptic area of 3- to 4-week-old mice have been detected and partially characterized. These components bind the respective hormones with high affinity (saturating at 4-8 nM) and sediment with rates typical of presumed steroid receptors (4.0-4.5 S in 0.15 M NaCl, 5.0-7.5 S without salt). A 90-95% reduction in androgen binding found in the androgen-insensitivity mutant mouse, testicular feminization (Tfm), provides a genetic control for the specificity of binding. This reduced androgen binding with Tfm/Y mutants and blocking experiments with non-radioactive estradiol [estra-1,3,5(10)-triene-3,17beta-diol] and testosterone (17beta-hydroxy-4-androsten-3-one) indicate the existence of at least two binding components: one with high affinity only for estradiol, the other with affinity for both androgens and estrogen. Based on these properties, a receptor mechanism that detects relative concentrations of androgens and estrogens is proposed.
TL;DR: Serum levels of DHA, DHAS, P, 17-OH-P, and A increased with the onset of genital and pubic hair growth and voice change; and testosterone increased withThe onset of penis growth, voice change and genital hair growth.
Abstract: Mean serum concentration dehydroepiandrosterone (DHA), DHA sulfate (DHAS), progesterone (P), 17-hydroxyprogesterone (17-OH-P), estrone (E1), estradiol (E2), and androstenedione (A) were compared from 43 boys followed longitudinally for as long as 4 yr during puberty. These data were also compared with serum levels of LH, FSH, and testosterone. Elevation is recognized early in puberty for DHAS, late in puberty for P and A, and gradually throughout puberty for E1, 17-OH-P, and DHA. When compared by age, the same general pattern is apparent with adult levels of E1 reached at age 12, DHAS and E2 by 13, and DHA, P, 17-OH-P, and A not until after age 15. Significant elevations of DHA occurred with the onset of pubic hair and voice change; elevations of DHAS occurred with the onset of genital and axillary hair growth; and testosterone increased with the onset of genital and pubic hair growth and voice change.