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15alpha-Hydroxyoestriol and other polar oestrogens in pregnancy monitoring.

Although oestriol measurements are well established for the assessment of 'at risk' pregnancies, there are a number of other oestrogens, excreted during pregnancy, which contain additional hydroxyl groups and might be more sensitive indicators of the condition of mother or fetus. Some of these result from the action of hydroxylases possibly present only in the fetus and others from maternal hydroxylations. We review the evidence for the biosynthesis of these polar oestrogens, summarise methods of measurement, and compare values obtained in normal and pathological pregnancies. There is as yet insufficient evidence to enable their potential value to be confirmed.

Catechols

The role of estrogen in the modulation of pituitary sensitivity of LRF (luteinizing hormone-releasing factor) in men.

The role of estradiol in modulating pituitary gonadotropin release in the human male was studied by evaluating the effects of clomiphene on the pituitary gonadotropin response to synthetic LRF (150 mug) in 6 eugonadal men. Administration of clomiphene (100 mg single daily dose time 5 days) induced a significant elevation of the basal levels of LH, FSH, estradiol and testosterone. However, the pituitary release of LH and FSH in response to LRF was markedly diminished by the clomiphene treatment. This finding suggests that in men, as in women, endogenous estradiol provides feedback regulation of gonadotropin output by the pituitary.

Adult

Effect of fluoxymesterone on the pituitary-gonadal axis: the role of testosterone-estradiol-binding globulin.

Four normal men and two agonadal men were given the oral synthetic androgen, fluoxymesterone (9alpha-fluoro-11beta, 17beta-dihydroxy-17alpha-methyl-4-androstene-3-one) for three days. Plasma testosterone (T), 17 alpha-hydroxyprogesterone (17-OHP), and LH were measured every 30 minutes on a control day and on the first day of treatment. Testosterone and LH were measured every six hours on the last day of treatment. During the first 24 hours of treatment the number of LH secretory episodes per day decreased from 10.5+/-2.5 (SD) to 6.2+/-2.9 (SD) (P less than 0.01), mean 24 hour LH decreased from 12.6+/-3.5 (SD) mlU/ml to 9.3+/-3.7 (SD) mlU/ml (P less than 0.01), and mean 17-OHP decreased from 2.33+/-1.4 (SD) ng/ml to 1.18+/-0.39 (SD) ng/ml (P less than 0.01) in all normal subjects. T was significantly decreased (P less than 0.01) from 464.5+/-76.4 (SD) ng/100 ml to 294.2+/-99.5 (SD) ng/100 ml. By the third day of treatment, LH had decreased further in four, and T in three of four normals. The number of LH spikes and the mean LH levels did not decrease in the agonadal patients. In vitro, using equilibrium dialysis, fluoxymesterone displaced T from plasma binding proteins with an apparent K=1.0 x 10(8) and 1.9 x 10(7) in female and male plasma, respectively, at 22 C; and 5.2 x 10(7) and 8.0 x 10(6) at 37 C. In polyacrylamide gel electrophoresis, a 500-fold molar excess of fluoxymesterone decreased the peak of TeBG-bound T by 45% (P less than 0.01). The in vitro data are consistent with the possibility that, in vivo, the displacement of T from TeBG by fluoxymesterone may play a role in the suppression of the pituitary-gonadal axis by synthetic oral androgens in vivo.

Adult

The effects of diethylstilbestrol and medroxyprogesterone acetate on kinetics and production of testosterone and dihydrotestosterone in patients with prostatic carcinoma.

Alterations in the metabolism of testosterone (T) and dihydrotestosterone (DHT) induced by diethylstilbestrol (DES) or medroxprogesterone acetate (MPA) could account for the beneficial therapeutic effect of these agents in prostatic carcinoma. To investigate this possibility we sutdied plasma kinetics of T and DHT in 17 elderly patients with prostatic carcinoma, before and after treatment with DES (1 or 5 mg/d) or MPA (10 or 30 mg/d) for 30 days. Metabolic clearance rates (MCR) were determined with the single injection technique and by use of two compartment model, plasma concentrations (PC) of T and DHT by radioimmunoassay, the per cent of T bound to plasma protein (T-binding) by charcoal adsorption of the unbound steroid. Production rate (PR) and PC of T were lower, PR and PC of DHT were higher in our patients than in normal men. With both DES regimens, PR, PC and MCR of either androgen declined; however, T was suppressed to a much greater extent than DHT. In either instance, the decrease may have been caused by direct suppression of testicular androgen synthesis and/or by decreased gonadotropin stimulation. Enhanced T-binding played an additional role in reducing the free testosterone index. High and low dose of DES were equally effective. The low dose regimen of MPA did not influence androgen metabolism. MPA in the higher dose suppressed PR and PC of T and DHT, possibly due to effects on testicular synthesis or by gonadotropin suppression as suggested for DES. In contrast to DES, MPA failed to cause profound changes in MCR of either androgen or in T-binding. When judged by its influence on the metabolism of T and DHT in prostatic carcinoma, MPA in higher doses is much less effective than either dose regimen of DES.

Aged

The effect of 7beta, 17alpha-dimethyltestosterone (calusteron) on testosterone metabolism in women with advanced breast cancer.

Calusterone (7beta, 17alpha-dimethyltestosterone) is a 17-alkylated, orally active androgenic steroid used in the treatment of breast cancer. The effect of this steroid on the metabolism of 14C-testosterone and the excretion of endogenous urinary androgen metabolites has been studied in four patients with breast cancer. Total glucuronide metabolites of the tracer decreased significantly, the andorsterone/etiocholanolone ratio rose by a factor of 2-4, and there was increased formation of uncharacterized polar metabolites. There was no significant change in either the sum of the excretion of endogenous androgen metabolites or the androsterone/etiocholanolone ratio. The changes resemble those we have seen in cirrhosis of the liver. It is concluded that the effects of Calusterone on testosterone metabolism, like its effects on cortisol or estradiol metabolism, represent nonspecific effects of an orally administered 17-alkylated steroid on hepatic structure and function, and probably bear no relationship to its therapeutic effect in breast cancer.

Androsterone

A comparison of the suppressive effects of testosterone and a potent new gonadotropin-releasing hormone antagonist on gonadotropin and inhibin levels in normal men.

GnRH antagonists have been developed in large part because of their potential use as contraceptive agents, particularly in men. Specifically, it was hoped that GnRH antagonists combined with testosterone (T) would be a more effective contraceptive regimen than T alone. We compared the suppressive effects of a potent GnRH antagonist, Na1-Glu [AcD2NaL1,D4ClPhe2,D3Pal3,Arg5,DGlu6(AA),+ ++DAla10-GnRH], and of T together and separately on serum and urinary gonadotropin and serum inhibin levels in normal men. Ten-day courses of Nal-Glu (75 micrograms/kg; Nal-Glu alone), 200 mg testosterone enanthate, im, on days 0 and 7 (T alone), and the combination (Na1-Glu + T) were given to nine men. Serum gonadotropin and inhibin concentrations decreased after 1-2 days of Na1-Glu administration, while gonadotropin suppression occurred more slowly after T alone. Serum T fell to 30% of baseline values during Na1-Glu administration. The combination of Na1-Glu + T was more effective in suppressing serum LH, FSH, and inhibin than was either Na1-Glu alone or T alone. All hormone levels returned to baseline levels within 2.5 weeks after the end of the three regimens. We conclude that the Na1-Glu GnRH antagonist effectively inhibits gonadotropin, inhibin, and sex steroid secretion when given daily for 10 days and that the administration of Nal-Glu + T results in more complete gonadotropin and gonadal suppression than that produced by either agent given alone. These results encourage further investigation of the combination of a GnRH antagonist and T as a male contraceptive regimen and of the antagonist alone as a treatment for hormone-dependent neoplasia.

Adult

Attenuation of mild hyperandrogenic activity in postpubertal acne by a triphasic oral contraceptive containing low doses of ethynyl estradiol and d,l-norgestrel.

The effect of a low dose triphasic oral contraceptive (OC) was evaluated during a 6-month treatment period in 41 patients (mean age, 25.4 +/- 0.7 yr) who had grade I-IV postpubertal acne and normal menses. The OC contained three dose levels of ethynyl estradiol and dl-norgestrel. Acne lesions were assessed, and serum androgen levels were measured during a control cycle and between days 17-21 of treatment cycles 1, 2, 3, and 6. Four patients dropped out after 3 months of treatment. Acne was significantly improved after the first OC cycle. After six cycles, the number of comedones had decreased by 79.6 +/- 3.2% (range, 50-100%) in 69.4% of the patients. Mean baseline levels of testosterone, 17-hydroxyprogesterone, and dehydroepiandrosterone sulfate were in the upper third of the normal range, with elevated individual values in 18.9%, 36.5%, and 26.8% of the women, respectively. Mean baseline levels of androstenedione, free testosterone (T), and 3 alpha-androstanediol glucuronide (3 alpha-diol-G) were above the normal range, with elevated individual values in 51.2%, 75.0%, and 85.4% of the patients, respectively. Sex hormone-binding globulin (SHBG) levels were below the normal range in 26.8% of the cases. At the end of the first OC cycle, there was a significant (P less than 0.01) decrease in all androgen precursors and a 2-fold increase in SHBG. Androstenedione and free T decreased into the normal range during OC intake. Serum 3 alpha-diol-G levels remained elevated, but had decreased by 34.5% at cycle 6 (P less than 0.05). These results show that the triphasic OC has significantly improved acne in postpubertal women for whom acne was the main manifestation of mild hyperandrogenic activity. The improvement in acne corresponded to a decrease in adrenal/ovarian androgens and free T, which led to a decreased metabolism to 3 alpha-diol-G, presumably by the sebaceous glands. The increase in SHBG is considered an estrogenic effect, and the triphasic formulation containing low dose dl-norgestrel is not androgenic but, rather, an estrogen-dominant formulation; as such, this product is recommended in women requiring contraception who also have idiopathic acne.

Acne Vulgaris

Gonadotropin-releasing hormone antagonist plus testosterone: a potential male contraceptive.

No effective hormonal contraceptive has yet been devised for men. Through their suppressive effect on gonadotropin secretion, GnRH antagonists inhibit both testosterone (T) production and spermatogenesis in animals. Long term administration of an antagonist alone would result in androgen deficiency; this would cause unacceptable physiological and behavioral sequellae in men. Therefore, androgen replacement must be included in any GnRH antagonist regimen used in human male contraception. We tested the hypothesis that the combination of a GnRH antagonist plus T would suppress spermatogenesis in the male primate to azoospermic levels while maintaining normal serum T levels. We examined the effects of the GnRH antagonist Deterelix [N-Ac-DNal(2)1-DpCl-Phe2-DTrp3-DhArg(Et2)6 -DAla10-GnRH], alone and with simultaneous T replacement, on sperm production and serum T levels in adult male monkeys (n = 22). After 12 weeks of daily sc antagonist injection, all animals that received antagonist alone (n = 5) and those that 750 micrograms/kg.day antagonist plus T (n = 5) were azoospermic. After 16 weeks, four of five animals that received 250 micrograms/kg.day antagonist plus T became azoospermic. Control animals (n = 7) received daily injections of vehicle; sperm counts increased somewhat during the study period in that group. Castrate range T levels were achieved in animals receiving antagonist alone. T levels in the groups that received T supplementation and in the control group were in the normal male range throughout the treatment period. Sperm counts returned to the pretreatment range in all animals during the recovery period. We conclude that the combination of a GnRH antagonist plus T can induce azoospermia reversibly in this nonhuman primates species, and that a similar combination may be an effective contraceptive regimen in men. The GnRH antagonist alone may be an effective treatment for androgen-dependent neoplasia.

Animals

Combined administration of a gonadotropin-releasing hormone antagonist and testosterone in men induces reversible azoospermia without loss of libido.

GnRH antagonists suppress pituitary and gonadal function by competing with endogenous GnRH for binding to receptors on pituitary gonadotrophs. We studied the effects of GnRH antagonist administration to men in a protocol simulating a likely male contraceptive regimen combined with a low dose of testosterone. The GnRH antagonist Nal-Glu was given daily (10 mg, sc) for 20 weeks to eight normal men, and a low dose of testosterone enanthate (25 mg, sc) was given every week. Sperm counts started declining during week 4, and complete azoospermia was reached within 6-12 weeks in six of the eight subjects. Subjects 7 and 8, whose sperm counts and serum gonadotropin levels were not suppressed after 10 weeks, were given 20 mg Nal-Glu starting at week 10. One became azoospermic at week 16, while the other's total sperm counts continued declining and reached a nadir of 1.4 million by week 20. Sperm motility and viability in this subject were completely suppressed after week 14. Sperm counts returned to baseline levels 12-14 weeks after the end of Nal-Glu administration. The mean serum LH level of the first six subjects decreased from 3 +/- 03. U/L at baseline to less than 0.1 U/L until week 20, and then levels returned to baseline. FSH levels similarly decreased from a combined mean of 3.6 +/- 0.9 U/L at baseline to below 0.3 U/L after 4 weeks of Nal-Glu administration. Serum mean testosterone levels between weekly injections of testosterone enanthate ranged from 27.4 +/- 5.9 to 4.8 +/- 1.4 nmol/L, but remained in the hypogonadal range (less than 10 nmol/L) for 4 of the 7 days. None of the subjects, however, complained of decreased libido or potency, as assessed by a questionnaire. No systemic or significant local side-effects were observed, other than a minimal reaction at the injection site. These data suggest that complete sustained azoospermia can be achieved in man, without loss of libido, by chronic administration of a GnRH antagonist plus testosterone.

Adult

A biodegradable testosterone microcapsule formulation provides uniform eugonadal levels of testosterone for 10-11 weeks in hypogonadal men.

Limitations of presently available testosterone esters (enanthate and cypionate) include the fluctuating serum testosterone levels and the need for relatively frequent injections (every 10-21 days). These limitations of testosterone esters have prompted the development of more physiological and longer acting systems for androgen delivery. This paper reports pharmacokinetic and pharmacodynamic data with a second generation long-acting testosterone microcapsule formulation in hypogonadal men. This was a single dose, open label, nonrandomized study. Ten hypogonadal men with primary (n = 6) or secondary (n = 4) hypogonadism, otherwise in good health, received 630 mg microencapsulated testosterone in dextran solution (IM) on day 1. Serum total and free testosterone; LH; FSH; dihydrotesterone; estradiol; sex hormone-binding globulin; total cholesterol; high, low, and very low density lipoprotein cholesterol; triglycerides; and apoprotein-AII and -B were measured on multiple occasions during the 2-week control period and the 16-week treatment period. In addition, on days 0, 1, 28, 56, and 84, subjects were hospitalized for detailed hormone analyses over the 24-h period. Serum total and free testosterone levels rose quickly into the midnormal range and stayed uniformly in the eugonadal range for about 70-77 days, after which serum testosterone levels declined gradually into the hypogonadal range. Testosterone release from the microcapsule formulation over the first 10 weeks approximated zero order kinetics. Serum dihydrotestosterone levels rose into the normal range, and testosterone to dihydrotestosterone ratios remained in the physiological range. Serum estradiol levels rose and stayed in the midnormal male range. Serum sex hormone-binding globulin levels decreased significantly during treatment. Serum LH and FSH levels also significantly decreased in the six hypergonadotropic men. Total cholesterol low and very low density lipoprotein cholesterol and triglyceride levels did not change, but plasma high density lipoprotein cholesterol levels decreased significantly during treatment. These data indicate that testosterone microcapsule formulation provides uniform eugonadal levels of testosterone for about 10 weeks. The long duration and zero order kinetics make it an attractive alternative to existing methods of androgen replacement.

Adolescent

[Preovulatory changes of steroidogenesis in isolated rabbit follicles (author's transl)].

In an attempt to investigate the effect of ovulating hormone on the steroidogenesis of mature follicles in the course of ovulation, transitory changes of steroidogenesis in isolated rabbit follicles have been studied at several intervals after injection of an ovulatory dose of human chorionic gonadotropin (hCG). Five to ten follicles of approximately 1-2 mm in diameter were isolated from ovaries of a mature rabbit (2.5-3.0 kg) under streomicroscope, before and at the 3rd, 6th, 9th and 12th hours after intravenous injection of of 100 IU/kg of hCG. Follicles were incubated with 100 muCi of acetate-1-14C in 2 ml of Krebs-Ringer bicarbonate buffer (pH 7.4) at 37 degrees C for 3 hours under 95% oxygen plus 5% carbon dioxide. Each incubation was terminated by quick freezing and stored forzen at -20 degrees C until eighty follicles had been collected for each time period before commencement of analysis. Incorporation of radioactive acetate into pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone., 20 alpha-dihydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, estrone and estradiol-17beta were analysed by the reverse dilution technique and identified in radiochemically pure form by recrystallization to constant specific activities. The steroidogenic activity of the follicles was evaluated by overall as well as fractionated incorporations. A peak in the overall incorporation of 14C- acetate into the ten steroids at the 3rd hour after hCG injection, followed by gradual decrease up to the 9th hour was observed. The incorporation decreased markedly to a minimum level at the 12th hour after hCG injection, which was below the level of preinjection control. Comparable quantitative fluctuations were found with the fractionated incorporation of 14C-acetate into the C21 and C18 steroids in the time sequence following hCG injection. However, the fractionated incorporation into C19 steroids reached to a maximum at the 6th hour after hCG injection. 5istribution patterns of incorporation among the individual steroids were varied at each interval of time. In the non-injected control, mature follicles synthesized predominantly estradiol-17beta, testosterone and androstenedione. Divergent steroids were formed from radioactive acetate at the 3rd hour after hCG injection. These included porgestogen, androgen and estrogen, but pregnenolone and 17hydroxyprogesterone were the two principal steroids produced. There was no essential difference in the steroidogenic patterns between the 6th and 9th hour, the major products being C21 and C19 steroids such as pregnenolone, 17hydroxyprogesterone, dehydroipiandrosterone and testosterone. The three androgens were the major steroids formed at the 12th hour after hCG injection. Thus the chages in the steroidogenic profile of the follicle was obvious in the course of ovulation. The basis of qualitative changes in follicular steroidogenesis during the process of ovulation have been discussed in connection with an accompanying effect of an ovulatory dose of hCG.

Acetates

Estrogens in maternal plasma following intraamniotic injection of (3H)-dehydroepiandrosterone-sulfate in midpregnancy.

In 4 patients with normal pregnancies between the 18th and 20th week of gestation (3H7alpha)-dehydroepiandrosterone-sulfate ([H]-DHEA-S) was injected intraamniotically. Maternal venous blood was drawn before and at regular intervals for 240 minutes after DHEA-injection. Thereafter, legal abortion was performed by intraamniotic instillation of prostaglandine. The conjugated steroids were hydrolyzed enzymatically and the total steroids were isolated and identified. The following labelled metabolites were determined quantitatively: Estriol (e3, estradiol-17beta (E2-17beta), estrone(E1), 16alpha-hydroxy-estrone, (16alpha-OH-DHEA), ALPHA4-androstenedione (AD) and testosterone (T). The maximal increase of all estrogen fractions in matermal plasma occurred 120-180min after intraamniotic injection of the precursor. The most prominent rise of the C18-steroids could be shown for estriol. 60-70% of all metabolites were C16-hydroxylated.

Amnion

Studies on the pattern of circulating steroids in the normal menstrual cycle. Circadian variation in theperi-ovulatory period.

Circadian variations of the plasma levels of dehydroepiandrosterone, 17-hydroxypregnenolone, pregnenolone and testosterone were investigated by radioimmunoassay in 10 normally menstruating women during the periovulatory period. In seven of the subjects it was also possible to estimate androstenedione and dihydrotestosterone levels. Blood was withdrawn continuously over a period of 48 h at a rate of 4 ml/h by means of a non-thrombogenic pump. The circadian rhythm was studied during 13 3-hour sampling periods (36 h) which were identical in all subjects. Dehydroepiandrosterone, 17-hydroxypregnenolone and pregnenolone showed a marked circadian rhythm with highest mean levels in the morning between 06.00 and 0.900 h and lowest mean levels during the night between 21.00 and 24.00 h. The peak levels of individual subjects coincided completely with the highest mean levels in the case of dehydroepiandrosterone, in 9 out of 10 cases with regard to 17-hydroxypregnenolone and in 8 of 10 cases as far as pregnenolone levels were concerned. The lowest individual levels were more dispersed around the means than were the individual peaks. The difference between the highest (morning hours: 06.00-09.00) and lowest (evening hours: 21.00-24.00) geometeric mean values was 404% for 17-hydroxypregnenolone, 163% for dehydroepiandrosterone and 71% for pregnenolone. The mean testosterone levels also exhibited an elevation between 06.00 and 09.00 h which was significant (P less than 0.05). However, the individual peak values were scattered from 21.00 h of the first day to 18.00 h of the second day. The mean concentrations of androstendine showed a significant increase between 06.00 and 18.00 h. The individual peaks were widely dispersed. Hence a uniform circadian rhythm correlated to the levels of the 5-steroids mentioned above could not be demonstrated in the case of testosterone and androstenedione. An analysis of variance indicated no significant differences between sampling periods as far as dihydrotestosterone levels were concerned. The extent and regularity of the circadian variation in the plasma levels of the 5-steroids studied makes it mandatory to standardize very carefully the exact time of blood withdrawal in any longitudinal study. In view of the sharp changes in the plasma levels during the morning hours, it is suggested that sampling during the afternoon period may provide more constant values.

17-alpha-Hydroxypregnenolone

The influence of combined cyproterone acetate-ethinyl oestradiol therapy on serum levels of dehydroepiandrosterone, androstenedione, and testosterone in hirsute women.

Serum levels of dehydroepiandrosterone, androstenedione, and testosterone in hirsute women suffering from either idiopathic hirsutism or the polycystic ovary syndrome were determined before and during treatment with cyproterone acetate combined with ethinyl oestradiol. During this treatment the hirsutism decreased markedly. In untreated hirsute women serum dehydroepiandrosterone levels do not differ from those in normal women and do not change during therapy; androstenedione levels are higher than normal and decrease markedly during treatment, and the testosterone levels are elevated compared to normals, with a considerable overlap, and show only a tendency to decrease. There is no correlation between dehydroepiandrosterone and androstenedione levels or between androstenedione and testosterone levels in the serum of untreated hirsute women. After 12-14 months of cyproterone acetate-ethinyl oestradiol therapy a linear correlation is found between dehydroepiandrosterone and androstenedione levels. This can be explained by the relatively higher contribution of the peripheral conversion of dehydroepiandrosterone to androstenedione to the occurrence of lower androstenedione levels. The linear correlation between androstenedione and testosterone after treatment, also found in normal women, indicates the restoration of the role of androstenedione as the major peripheral precursor of testosterone.

Adolescent

The effect of RMI 12, 936 synthetic antiprogestional steroid, on ovarian steroidogenesis in the rat.

A series of physiochemical investigations confirmed that the product of chemical and enzymatic isomerization of RMI 12,936 was 7alpha-methyltestosterone. The total activity per pair of ovaries of delta5 3-ketosteroid isomerase in vitro was unchanges by RMI 12,936 pretreatment or by advancing pregnancy, significant changes in ovarian weight being accompanied by reciprocal changes in enzyme activity/mg tissue. The initial rate of isomerization of RMI 12,936 was approximately five times greater than the corresponding rate of delta5-progesterone isomerization at equal substrate concentrations. It is concluded that RMI 12,936 does not inhibit progesterone biosynthesis by alteration of delta5 3-ketosteroid isomerase activity, but that it may do so by acting as an alternative substrate for this enzyme.

Androstenols

The effects of ligation of vas deferens, corpus epididymidis and vasa efferentia on the testicular function in rats.

The effects of ligation of the vas deferens, the corpus epididymidis and the vasa efferentia on the testicular function were studied in sexually mature rats. The significant decrease in the testicular weight was observed after ligation of the corpus epididymidis and the vasa efferentia. However, neither the weight of the ventral prostate and of the seminal vesicle, nor the plasma testosterone level showed significant changes. The results suggest that the ligation at the three locations would not affect the endocrine function of the testis. The changes in the testis would mainly affect the spermatogenesis. The effects of sperm stasis on the testicular function were also discussed.

Animals