Showing papers on "Testosterone published in 1972"
TL;DR: It appears that stress causes an increase in the weak adrenal androgen, androstenedione, from the maternal or fetal adrenal cortices, or from both, and a concurrent decrease in the potent gonadal androgens, testosterone.
Abstract: Male rats were exposed to prenatal or postnatal stress, or both. The prenatally stressed males showed low levels of male copulatory behavior and high rates of female lordotic responding. Postnatal stress had no effect. The modifications are attributed to stress-mediated alterations in the ratio of adrenal to gonadal androgens during critical stages of sexual differentiation. Specifically, it appears that stress causes an increase in the weak adrenal androgen, androstenedione, from the maternal or fetal adrenal cortices, or from both, and a concurrent decrease in the potent gonadal androgen, testosterone.
533 citations
TL;DR: It was observed that plasma testosterone levels and the apparent free plasma testosterone concentration remain within the same range from adolescence until the age of 50 yr, but that from the 6th decade on, the mean plasma levels decrease rather rapidly, with a wide range of individual values.
Abstract: The influence of aging on plasma testosterone levels and testosterone metabolism in males was studied. It was observed that plasma testosterone levels and the apparent free plasma testosterone concentration (AFTC) remain within the same range from adolescence until the age of 50 yr, but that from the 6th decade on, the mean plasma levels decrease rather rapidly, with however a wide range of individual values. As the metabolic clearance rate (MCR) decreases in male senescence, the net result is an important decrease in the testosterone blood production rate. Within the group of subjects studied, a statistically significant correlation between the free testosterone fraction and the MCR was found. It was observed that testosterone metabolism in male senescence is characterized by a relative decrease of the formation of androstanediols, with a relative increase of 5β over 5α metabolites;moreover a statistically significant correlation between the formation of 5α-androstane-3α,17β-diol and the free testosteron...
525 citations
TL;DR: Gonadal hormones have important effects on the behaviors that determine body weight in laboratory rats, and may act directly on separate neural loci to inhibit food intake and stimulate locomotor activity, possibly by lowering the set-point of a hypothalamic lipostat.
371 citations
TL;DR: A rapid and simple method for the measurement of testosterone-estradiol-binding globulin in human plasma is described, and normal values were observed in abstinent alcoholics and in pregnant subjects with diabetes or hypertension.
Abstract: A rapid and simple method for the measurement of testosterone-estradiol-binding globulin in human plasma is described. The bind- ing protein is saturated with dihydrotestosterone (DHT), precipitated with 50% ammonium sul- fate, and the mass of bound DHT determined from the known specific activity of the added steroid. Normal values, expressed as M-g DHT bound/100 ml serum are: men, 0.93 ±. 0.06 (SEM); women, 1.85 ± 0.13; pregnancy, 12.4 ± 0.67. Elevated values were observed in men with cirrhosis of the liver and patients with thyrotoxi- cosis. Normal values were observed in abstinent alcoholics and in pregnant subjects with diabetes or hypertension. (/ Clin Endocrinol Metab 34: 983, 1972)
350 citations
TL;DR: A comparative study in castrated rats revealed that Sch 13521 was equipotent to cyproterone acetate (CPA) as an antiandrogen, but unlike CPA, it did not effect parturition time.
Abstract: Sch 13521 (4'–nitro–3'–trifluoromethylisobutyranilide) at daily doses from 1–50 mg/kg reduced seminal vesicles and ventral prostate wt of intact male rats treated orally for 1–3 weeks. No alterations in sex structures of female rats were observed with doses as high as 50 mg/kg. Sch 13521 antagonized the effects of testosterone, testosterone propionate, androstenedione, and dihydrotestosterone on seminal vesicles and ventral prostate wt in castrated rats as well as the effects of hCG in hypophysectomized rats. A comparative study in castrated rats revealed that Sch 13521 was equipotent to cyproterone acetate (CPA) as an antiandrogen. However, when Sch 13521 was given to gravid rats, days 16–19, it reduced the anogenital distance in male fetuses and altered the normal development of the scrotum and penis, but unlike CPA, Sch 13521 did not effect parturition time. In the majority of these male rats, hypospadias and vaginal tracts were present and ventral prostates and seminal vesicles were absent or markedly...
338 citations
TL;DR: The role of the human testis in the production of 17beta-estradiol (E(2)) was investigated by determining the concentration of E(2) and testosterone in peripheral and spermatic vein plasma samples.
Abstract: The role of the human testis in the production of 17beta-estradiol (E(2)) was investigated by determining the concentration of E(2) and testosterone in peripheral and spermatic vein plasma samples. Specimens were obtained from eight normal men, three men with hypogonadism, and two patients with the incomplete form of the feminizing testes syndrome. For comparison, similar studies were performed in four monkeys, 10 mongrel dogs, and 4 additional dogs who were given 1000 IU of human chorionic gonadotropin/day for 5 days. Plasma E(2) was measured by radioimmunoassay utilizing sheep anti-E(2) serum preceded by ether extraction and thin layer chromatographic separation of plasma steroids. Procedural blanks, which were subtracted from all reported values were 14.1+/-0.74 (SEM) pg for deionized water and 13.1+/-0.66 pg for charcoaladsorbed pooled male plasma. Pooled male and pooled female control plasmas averaged 17+/-0.71 pg/ml and 95+/-6.9 pg/ml, respectively; individual adult male specimens ranged between 8 and 28 with a mean of 18+/-1.4 pg/ml. In the eight normal men, the mean peripheral vein E(2) concentration was 20+/-1.6 pg/ml, while the spermatic vein concentration was 50 times as great, 1049+/-57 pg/ml. All three patients with testicular abnormalities had low spermatic vein E(2) concentrations (160, 280, and 416 pg/ml). Lesser E(2) gradients were found across the simian (3-fold) and canine (approximately 12-fold) testes. Testicular testosterone gradients (human 110-, simian 10-, and canine 77-fold) were greater than the E(2) gradients in all three species. In four dogs, HCG treatment elicited a 6-fold increase in peripheral and a 9-fold increase in spermatic vein testosterone concentrations; however, peripheral and spermatic vein E(2) concentrations did not differ from control values. Spermatic vein E(2) concentrations were > 4600 and 2210 pg/ml (post-HCG) in two patients with the incomplete form of the feminizing testes syndrome. Postorchiectomy, peripheral E(2) and testosterone concentrations fell precipitously in both patients, confirming the major contribution of the testes, in this syndrome, to circulating E(2) and testosterone. These studies provide direct evidence that the human testic secretes estradiol.
224 citations
TL;DR: It is shown that estrogen can directly stimulate the uterus without the requirements of intact vascular or nervous systems and shows a strict hormonal specificity.
208 citations
TL;DR: A novel biological role for a specific plasma-binding protein in the regulation of oestrogen and androgen activity in man is suggested.
Abstract: WE suggest a novel biological role for a specific plasma-binding protein in the regulation of oestrogen and androgen activity in man. The biological activity of oestradiol and testosterone, as with other steroids1, is probably exerted by the unbound fraction in plasma; this is only 1–3% of the total concentration. The plasma proteins that bind testosterone and oestradiol include sex-hormone-binding β globulin (SHBG)2, which has high affinity for both steroids; and albumin, which has low affinity but is present in three thousand times the concentration. Further, corticosteroid-binding globulin (CBG) binds testosterone3 though its main affinity is for cortisol and progesterone.
205 citations
TL;DR: Following chemotherapy, testicular damage was restricted to the germinal tissue, and this in turn was associated with a selective increase in FSH, since FSH levels are only half as high as those reported for castrate men, other testicular factors may modify FSH secretion.
Abstract: The interaction of the testis and gonadotropin secretion was studied in 15 men surviving chemotherapy for lymphoma. Azoospermia and complete destruction of all testicular germinal elements were present in 10 of the 15 men; however, Sertoli cells and Leydig cells were present. In these 10 men plasma follicle-stimulating hormone (FSH) levels were fourfold higher than in normal men of similar age whereas luteinizing hormone (LH) levels were normal. In contrast, both FSH and LH were normal in the remaining five men. Three had a full complement of spermatogenic tissue on biopsy and normal sperm concentrations. The other two men were azoospermic; one demonstrated full spermatogenesis in 30% of his tubules; the other had only a few spermatogonia in all tubules. In those patients with lower levels of gonadotropins pituitary insufficiency was excluded by the demonstration of appropriate responsiveness of FSH and LH to clomiphene administration. Similarly, Leydig cell function was normal since plasma testosterone was within the normal range in 13 of the 15 men and only slightly decreased in two. Thus, following chemotherapy, testicular damage was restricted to the germinal tissue, and this in turn was associated with a selective increase in FSH. The source of the FSH inhibitor is either the Sertoli cell or early germinal elements. However, since FSH levels are only half as high as those reported for castrate men, other testicular factors may modify FSH secretion.
190 citations
TL;DR: The surprising finding of luteal range serum progesterone levels in many early postmenarchal girls suggests that anovulatory cycles may not be characteristic of these years, and reported relative infertility of adolescent girls may relate to factors other than ovulation.
Abstract: Extract: Data are provided which concern daytime levels of circulating follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol and progesterone in healthy female children and adolescents. These findings are correlated with sexual and skeletal maturation. Serum estradiol and testosterone levels were low in childhood, but rose to adult levels coincident with the appearance of secondary sexual characteristics. Serum LH levels did not rise above prepubertal levels until these characteristics were already apparent. Serum FSH levels showed a biphasic pattern with age; widely scattered values, some into the adult range, were seen in infancy. Mean FSH levels then declined throughout childhood until the onset of clinical puberty at which time they increased again to adult levels. Serum progesterone concentrations remained low (below 150 ng/100 ml) until menarche. Levels of serum progresterone which suggested possible ovulation and corpus luteum formation (over 200 ng/100 ml) were found in 9 of 30 girls who were less than 3 years postmenarchal. Speculation: The finding of high serum FSH levels in female, but not in male, infants suggests that the infantile ovary may be relatively resistant to FSH stimulation. The decline in FSH levels during early childhood may represent increasing ovarian maturation, at least in terms of ability to secrete as yet unidentified gonadotropin-inhibiting feedback substance (or substances). The onset of female puberty appears to be heralded by increasing FSH secretion; although nocturnal LH release may be characteristic of early puberty, daytime elevation of this hormone is not seen until midpuberty. The surprising finding of luteal range serum progesterone levels in many early postmenarchal girls suggests that anovulatory cycles may not be characteristic of these years. The reported relative infertility of adolescent girls may relate to factors other than ovulation (such as a short corpus luteum life-span, defects in sperm capacitation, or impaired blastocyst implantation).
189 citations
TL;DR: The testosterone production rate must be measured in hirsute women if a complete assessment of androgen metabolism is to be made, and the origin of testosterone in normal and virilized women can best be determined by a combination of steroid kinetic studies and direct sampling of adrenal and ovarian venous effluents.
Abstract: There is considerable biologic evidence indicating that testosterone is the most important androgen in women. Testosterone production rates have been elevated in almost every virilized patient studied to date. Clinical evaluation of the hirsute patient, however, is complicated by the observation that plasma testosterone alone may not adequately reflect testosterone production. This relates to the fact that plasma androgen levels in women may be independently influenced by the rate of steroid entry into blood (production rate) as well as removal from blood (clearance). The testosterone production rate must be measured in hirsute women if a complete assessment of androgen metabolism is to be made. The origin of testosterone in normal and virilized women can best be determined by a combination of steroid kinetic studies and direct sampling of adrenal and ovarian venous effluents. In normal women about 65% of plasma testosterone is derived from plasma prehormones (androstenedione and dehydro-epiandrosterone) and 35% is apparently secreted by adrenals and ovaries. In clear-cut cases of adrenal or ovarian disease, excessive androgen production can usually be traced to the abnormal organ. In most women with idiopathic hirsutism, the ovaries, rather than the adrenals, are the most common sites of androgen oversecretion.
TL;DR: The expression of agonistic behavior was potentiated by androgen; aggressiveness and dominance were also greatly influenced by residence in the home cage.
TL;DR: Direct experimental evidence is provided in support of the view that male pseudohermaphroditism in testicular feminization is the result of resistance to androgen action during androgen-mediated sexual differentiation in embryos.
Abstract: The pathogenesis of the male pseudohermaphroditism in the mouse with X-linked testicular feminization (Tfm) has been investigated by comparing testosterone formation, the effects of androgen administration, and the metabolism of testosterone-1,2-(3)H in normal mice and Tfm mice of varying ages. First, it was established that the adult Tfm animal, in contrast to the human with testicular feminization, has both a low serum testosterone and a low rate of testosterone formation as assessed in slices of testes utilizing a variety of precursors. However, the formation of testosterone from pregnenolone-7alpha-(3)H was shown to be normal in newborn Tfm testes, suggesting that a defect in testosterone synthesis may not be primary to this mutation. Second, to establish that the pseudohermaphroditic state is due to androgen resistance rather than to diminished androgen biosynthesis during fetal life, the effect of the administration of dihydrotestosterone to pregnant animals was studied in male, female, and Tfm offspring. Whereas normal and carrier female littermates demonstrated striking virilization of the internal genital tract after such treatment, there was no sign of virilization in the Tfm animals. This finding provides direct experimental evidence in support of the view that male pseudohermaphroditism in testicular feminization is the result of resistance to androgen action during androgen-mediated sexual differentiation in embryos. Third, the metabolism of testosterone-1,2-(3)H was investigated both in tissue slices and in functionally hepatectomized animals. Dihydrotestosterone formation in tissue slices of the fetal anlage of the male organs of accessory reproduction is normal in the Tfm animal, suggesting that the primary defect in this disorder involves an intracellular event subsequent to this step and that the deficient dihydrotestosterone formation observed in the adult genital tract of the Tfm mouse is secondary to the failure of differentiation in these tissues. Finally, deficient binding of testosterone in the nuclei of the submandibular gland of adult Tfm animals, a known testosterone target tissue, was demonstrated in functionally hepatectomized mice. This finding could either be a manifestation of the primary genetic defect in this disorder or might reflect another acquired abnormality due to incomplete differentiation of adrogen-sensitive cell lines.
TL;DR: In a child with male pseudohermaphroditism (ambiguous external genitalia, XY sex chromosomal constitution and normal adrenocortical function), incubations of testicular tissue with pregnenolone/progesterone showed that testosterone could be formed from androstenedione and dehydroepiandrosterone only, but not from other substrates.
Abstract: SUMMARY
In a child with male pseudohermaphroditism (ambiguous external genitalia, XY sex chromosomal constitution and normal adrenocortical function), incubations of testicular tissue with pregnenolone/progesterone, 17α-hydroxy-pregnenolone/17α-hydroxyprogesterone and androstenedione/dehydroepiandrosterone showed that testosterone could be formed from androstenedione and dehydroepiandrosterone only, but not from other substrates. In urine, testosterone did not increase after HCG, but small amounts of pregnanetriolone were found, which increased after HCG and ACTH. There was no DHA increment after ACTH.
It is concluded that this patient, as well as a first cousin and a gonadectomized maternal 'aunt' with the same clinical and urinary steroid findings have testicular and adrenal steroid 17,20-desmolase deficiency, causing a defect of androgen biosynthesis, which has not previously been described. The heredity of this condition seems to be autosomal or X-chromosomal.
TL;DR: It was concluded that androgen-sensitive structures regulating male sexual behavior in the rat are more concentrated in the anterior than the posterior hypothalamic region and testosterone probably does not activate maleSexual behavior via conversion to dihydrotestosterone.
TL;DR: It is conceivable that the hormone affects certain muscles through an increased (sexual or general) activity by way of the central nervous system, or because of the release of another hormone, or secondarily through some change of general metabolism.
Abstract: IT is not known whether the “anabolic” action of the androgenic hormone testosterone1, especially on muscular growth and metabolism, can be explained by the presence and the possible metabolism and “receptors” of the hormone in muscles. There are indeed several categories of muscles which, when dependent on androgens, may or may not respond directly to testosterone. It is conceivable that the hormone affects certain muscles through an increased (sexual or general) activity by way of the central nervous system, or because of the release of another hormone, or secondarily through some change of general metabolism.
TL;DR: The ability to transform testosterone into DHT is much higher in all structures examined (with the exception of the prostate) in prepuberal than in adult rats.
TL;DR: It was possible to identify a group of boys in whom the only sign of adolescence was early testicular enlargement, who demonstrated a significantly greater testosterone levels, and this observation indicates that the response to HCG stimulation may used to differentiate anorchia from cryptorchidism.
Abstract: The response in circulating testosterone and estradiol concentrations following daily injections of 2000 IU of human chorionic gonadotropin (HCG) was studied in 68 healthy males aged 5.5 to 21.9 years. A significant increment in testosterone levels was seen at all ages after either 1 or 3 injections. A measurable rise in plasma estradiol was seen only after early adolescence was clinically apparent. The magnitude of the testosterone and estradiol responses increased with age, the stage of sexual development and correlated with rising endogenous serum FSH and LH concentrations. No rise in plasma testosterone after HCG was seen in four anorchic males, but four boys with intra-abdominal testes showed a significant response. This observation indicates that the response to HCG stimulation may used to differentiate anorchia from cryptorchidism. It was possible to identify a group of boys in whom the only sign of adolescence was early testicular enlargement, who demonstrated a significantly greater testosterone ...
TL;DR: Dihydrotestosterone, an A-ring reduced steroid which is not convertible to estrogen, was demonstrated to be more potent than testosterone in suppressing serum LH levels while equipotent toosterone in suppressing FSH.
TL;DR: Effects of major surgical stress on plasma concentrations of testosterone and immunoreactive luteinizing hormone (LH) were studied in 25 male patients and showed a significant fall in LH concentration on the 2nd post-operative day.
Abstract: Effects of major surgical stress on plasma concentrations of testosterone and immunoreactive luteinizing hormone (LH) were studied in 25 male patients. Significantly decreased levels of testosterone from the pre-operative level (0.66 ± 0.03 (se) μg/100 ml) were found during the operation. On the other hand, plasma LH increased significantly from the pre-operative level [4.27 ± 0.29 (se) μg/100 ml] during the operation and reached the maximum concentration 30 min after the beginning of incision [8.28 ± 0.71 (se) μg/100 ml]. Shortly after the end of the operations, the mean concentration of LH had returned to its pre-operative level, but the mean concentration of testosterone continued to fall. No such change explainable by diurnal variation was observed in 10 male patients followed for a similar period of time prior to surgery. The patients exhibited a significant fall in LH concentration on the 2nd post-operative day [3.11 ± 0.24 (se) μg/100 ml], when plasma testosterone showed the most marked de...
TL;DR: The integrated concentration of growth hormone (ICGH) is markedly elevated in some boys prior to onset of puberty or elevation of plasma testosterone, in contrast to earlier reports that both exogenous and endogenous androgens may stimulate the growth hormone response to arginine and/or insulininduced hypoglycemia.
Abstract: The integrated concentration of growth hormone (ICGH) was studied in 17 normal preadolescent and adolescent boys and 16 normal adult males. The ICGH was determined over a 16–24 hour period under normal ambulatory conditions without the use of exogenous stimuli. The mean ± SD ICGH of 5.6 ± 3.6 ng/ml for the boys is significantly higher than the mean of 1.8 ± 1.0 for adult males. There is not an increase in ICGH associated with increase in bone age, progression of puberty, or increase in plasma testosterone. ICGH is markedly elevated in some boys prior to onset of puberty or elevation of plasma testosterone. This is in contrast to earlier reports that both exogenous and endogenous androgens may stimulate the growth hormone response to arginine and/or insulininduced hypoglycemia.
TL;DR: The results suggest that gonadal stero id levels present during prenatal and postnatal developmental stages determine the direction and degree of differentiation of adult rat sexual behavior and that male behavior in normal females is based on pre natal androgenic modifications of the nervous system.
Abstract: Consequences of perinatal hormone manipulation on the adult sexual b ehavior of female rats were investigated. The animals were injected wit h oil prenatal or prolonged postnatal testosterone propionate (TP) or cyproterone acetate (Cyp A). Prenatal TP decreased quality and rate of lordotic response. Postnatal TP also impaired female behavior but increased the complete male compulatory rate. Prenatal Cyp A reduced the copulatory rate (p less than .01) while prenatal TP increased it (p less than .05). Both prenatal and postnatal TP produced equally large ( p less than .05) increases in number of complete copulations. Rats receiving prenatal Cyp A showed marked reductions in the percentage of animals displaying complete copulations while those who received only po stnatal Cyp A were unaffected. These results suggest that gonadal stero id levels present during prenatal and postnatal developmental stages determine the direction and degree of differentiation of adult rat sexual behavior and that male behavior in normal females is based on pre natal androgenic modifications of the nervous system.
TL;DR: The use of LH/FSH-RH will provide an important test to define the level of the lesion in hypogonadal patients and also should be valuable in the treatment of some types of male and female infertility.
Abstract: The effects of the gonadotrophin-releasing hormone, synthetic decapeptide luteinizing hormone/follicle stimulating hormone-releasing hormone (LH/FSH-RH), have been studied in 18 normal men and five women in the follicular phase of their menstrual cycle. Rapid and dose-dependent (25 to 100 μg) increases in serum immunoreactive LH were seen, which reached a peak 20 to 30 minutes after a rapid intravenous injection. Similar but much smaller increases in serum immunoreactive FSH were seen. These conclusions have been validated by using two different immunoassay systems for each hormone. The LH/FSH-RH therefore causes both LH and FSH release in man as in animals but does not affect growth hormone, thyrotrophin, or ACTH. The gonadotrophin responses were the same in the women as in the men but were insufficient in the men to cause statistically significant changes in the serum levels of the gonadal steroid hormones, testosterone or oestradiol, or in their precursors 17 α-hydroxyprogesterone or progesterone. In the women, however, there was a rise in oestradiol after the 100-μg doses. The use of LH/FSH-RH will provide an important test to define the level of the lesion in hypogonadal patients and also should be valuable in the treatment of some types of male and female infertility. A simple and clinically useful LH/FSH-RH test of pituitary function is described (100 μg given intravenously), and the provisional normal responses of LH and FSH at 20 and 60 minutes are given.
TL;DR: The steroidogenic response of the isolated rat testis to gonadotropic hormones was measured by radioimmunoassay of testosterone released during incubation in vitro with human chorionic gonadotropin (HCG) and luteinizing hormone (LH) and validated by reference to specific testosterone assays employing extraction and chromatography.
Abstract: The steroidogenic response of the isolated rat testis to gonadotropic hormones was measured by radioimmunoassay of testosterone released during incubation in vitro with human chorionic gonadotropin (HCG) and luteinizing hormone (LH). Measurement of testosterone production by radioimmunoassay of incubation media was validated by reference to specific testosterone assays employing extraction and chromatography prior to measurement by competitive protein binding and radioimmunoassay. During incubation of individual testes in vitro, testosterone production rose slowly to the basal level of 100-200 ng/testis/4 hr. Addition of 20 ng (7.2 X 10-11M) HCG or 10-3M dibutyryl cyclic AMP caused a marked rise in testosterone production, detectable after IS min and increasing throughout the period of incubation. The decapsulated adult rat testis was extremely sensitive to gonadotropin stimulation in vitro, responding with increased testosterone release to as little as 1 mlU (0.2 ng) HCG, 2.5 mlU (0.7 ng) human LH, and 0...
TL;DR: The differential action of serotonin and melatonin on the 17βhydroxysteroid dehydrogenase system is consistent with the hypothesis that the metabolism of serotonin as it related to age changes in the rat.
Abstract: Carbon-14-labeled progesterone, 17α-hydroxyprogesterone, androstenedione, and testosterone were incubated with rat testicular preparations with and without serotonin or melatonin. Serotonin inhibited 17α-hydroxylase, 17α-hydroxypregnene-C17-C20-lyase, and 17-keto reductase activities. Serotonin increased 17P-hydroxysteroid dehydrogenase activity, but decreased 20α-reductase for 17α-hydroxyprogesterone. Melatonin also inhibited 17ot-hydroxylase, 17α-hydroxypregnene- C17-C20-lyase and 17β-hydroxysteroid dehydrogenase, but not 17-keto reductase activities. It increased 20a-reductase activity. Serotonin and melatonin altered the A/T ratios in the incubations. The effects of serotonin on steroid biotransformations correlated well with recent reports of the presence of serotonin in testicular tissue and with the metabolism of serotonin as it related to age changes in the rat. The differential action of serotonin and melatonin on the 17βhydroxysteroid dehydrogenase system is consistent with the hypothesis that t...
TL;DR: In three patients with testicular feminization syndrome (an adult with hyperthyroidism and two children) these two MCRs were greatly reduced compared to the normal females, but the conversion of testosterone into dihydrotestosterone was in the limits of normal male range.
Abstract: The metabolic clearance rate (MCR) and blood production rate (BP) of testosterone (T) and dihydrotestosterone (DHT), the conversion of plasma testosterone to plasma dihydrotestosterone, and the renal clearance of androstenedione, testosterone, and dihydrotestosterone have been studied in man. In eight normal men, the MCR(T) (516+/-108 [SD] liters/m(2)/day) was significantly greater than the MCR(DHT) (391+/-71 [SD] liters/m(2)/day). In seven females, the MCR(T) (304+/-53 [SD] liters/m(2)/day) was also greater than the MCR(DHT) (209+/-45 [SD] liters/m(2)/day) and both values were less than their respective values in men (P < 0.001). In men the conversion of testosterone into dihydrotestosterone at 2.8+/-0.3% (SD) was greater than that found in females, 1.56+/-0.5% (SD) (P < 0.001). In five pregnant females the MCR(T) (192+/-36 [SD] liters/m(2)/day), the MCR(DHT) (89+/-30 [SD] liters/m(2)/day) and the conversion of testosterone into dihydrotestosterone (0.72+/-0.15%) (SD) were significantly less than the values found in nonpregnant women. In five females with hyperthyroidism, the MCR for testosterone and dihydrotestosterone were similar to those observed in pregnant females, but the conversion of testosterone into dihydrotestosterone (2.78+/-1.7%) (SD) was greater, and similar to that found in men. In men the production of dihydrotestosterone was 0.39+/-0.1 (SD) mg/day, 50% being derived from the transformation of plasma testosterone. In women the production of DHT was 0.05+/-0.028 (SD) mg/day, only 10% coming from testosterone. During pregnancy, the production of testosterone and dihydrotestosterone are similar to that in normal women. In three patients with testicular feminization syndrome (an adult with hyperthyroidism and two children) these two MCRs were greatly reduced compared to the normal females, but the conversion of testosterone into dihydrotestosterone was in the limits of normal male rangeIn the normal subjects the renal clearance of androstenedione was greater than that of testosterone and dihydrotestosterone. Less than 20% of the dihydrotestosterone and less than 10% of the androstenedione in the urine is derived from the plasma dihydrotestosterone and androstenedione.
TL;DR: Following orchidectomy, in both patients, the concentration of plasma androgens was quivalent to that in a normal female, and the estrogens similar to a post-menopausal woman.
Abstract: A patient with masculine pseudohermaphroditism was considered as a normal female until puberty. At puberty she had normal breast development, primary amenorrhea and marked signs of virilism. The peripheral and spermatic venous plasma concentration of dehydroepiandrosterone (DHA) and its sulfate, androstenedione (Δ), testosterone (T), estrone (E1) and 17β-estradiol (E2) were measured in this patient and in a case of testicular feminization syndrome. In the latter patient T was the principal androgen secreted by the testicle and E2 the principal estrogen. In the first patient, the secretion of T was small, and that of Δ greatly increased; the secretion of E1 was increased more than that of E2. Following orchidectomy, in both patients, the concentration of plasma androgens was quivalent to that in a normal female, and the estrogens similar to a post-menopausal woman.
TL;DR: The conversion of testosterone-4-14C to dihydrotestosterone (17β-Phydroxy-5α-androstan-17-one), the tissue-active androgen, is demonstrated with 50–200 μg of freeze-dried human hair follicles plucked from various regions with 5α-reductase activity.
Abstract: We demonstrated the conversion of testosterone-4-14C to dihydrotestosterone (17β-Phydroxy-5α-androstan-17-one), the tissue-active androgen, with 50–200 μg of freeze-dried human hair follicles plucked from various regions. All of the hair follicles thus far tested contained the 5α-reductase activity. Under optimal conditions, the 5α-reductase activity in growing hair follicles ranged from 10–20 nmoles/100 mg dry wt/hr. In the scalp, the growing follicles showed 3–8 times higher values than the resting. In other regions such as the beard, axilla, chest, pubis, arms and legs, the growing follicles showed nearly the same activities as those of the scalp or even higher, whereas the activities of the resting follicles varied considerably.
TL;DR: Results are consistent with the hypothesis that development of male sexual behavior is dependent upon the presence of estrogen or androgen which can be metabolized to estrogen during sexual differentiation and suggest that the induction of masculine behavior results from a central neural hormone action.