SUPRESSION OF ANDROGEN AND OESTROGEN PRODUCTION IN NORMAL MEN

1972 ◽  
Vol 70 (2) ◽  
pp. 342-350 ◽  
Author(s):  
M. A. Kirschner ◽  
D. W. R. Knorr
Keyword(s):  
Urine Sample ◽  
Plasma Testosterone ◽  
Low Level ◽  
Normal Men

ABSTRACT An attempt was made to suppress production of androgens and oestrogens in normal men by administering large doses of exogenous androgens and corticoids. After 5 days of 40 mg fluoxymesterone qd, plasma testosterone concentrations decreased from 509 to 73 ng/100 ml (85%); on adding 8 mg qd of dexamethasone, there was a further decrease to 45 ng/100 ml. Androstenedione concentrations were decreased equally by fluoxymesterone and corticoids. To monitor the suppressive effects of exogenous steroids, urinary LH was followed serially by radioimmunoassay, and decreased to only 40% of control levels after 5 days of fluoxymesterone, with no further suppression noted on adding dexamethasone. Nanogram quantities of steroidal metabolites were not adsorbed by kaolin extraction of urine, thus enabling gonadotrophins (kaolin extract) and low-level steroids (supernate) to be measured in the same urine sample. Urinary oestrone and oestradiol excretion decreased during 5 days of fluoxymesterone, and continued to fall when dexamethasone was added. In no case was oestrone or oestradiol excretion, urinary LH or plasma androgens completely suppressed by large doses of fluoxymesterone alone, or in combination with large doses of dexamethasone.

EFFECT OF ETHINYLOESTRADIOL ON PLASMA TESTOSTERONE LEVELS AND URINARY TESTOSTERONE EXCRETION IN MAN

1965 ◽  
Vol 50 (1) ◽  
pp. 51-54 ◽  
Author(s):  
Enrico Forchielli ◽  
Govind S. Rao ◽  
Inder R. Sarda ◽  
Norman B. Gibree ◽  
Peter E. Pochi ◽  
...  
Keyword(s):  
Oral Administration ◽  
Plasma Testosterone ◽  
Testosterone Levels ◽  
The Mean ◽  
Normal Men ◽  
Daily Oral Administration

ABSTRACT The daily oral administration of one mg of ethinyloestradiol to normal men decreased the mean plasma testosterone from 0.84 ± 0.07 μg per 100 ml to 0.20 ± 0.04 in 21 trials and decreased the urinary testosterone from 63 ± 1.1 μg per day to 8 ± 0.3 in 16 trials.

scholarly journals Evaluation of endocrine testing of Leydig cell function using extractive and recombinant human chorionic gonadotropin and different doses of recombinant human LH in normal men

2008 ◽  
Vol 159 (2) ◽  
pp. 171-178 ◽  
Author(s):  
Anne Cailleux-Bounacer ◽  
Yves Reznik ◽  
Bruno Cauliez ◽  
Jean François Menard ◽  
Céline Duparc ◽  
...  
Keyword(s):  
Chorionic Gonadotropin ◽  
Leydig Cell ◽  
Cell Function ◽  
Dose Effect ◽  
Plasma Testosterone ◽  
Testosterone Levels ◽  
Plasma Estradiol ◽  
Normal Men ◽  
Dose Dependent ◽  
Leydig Cell Function

BackgroundThe functional testing of endocrine testis uses extractive human chorionic gonadotropin (ehCG). Recombinant human hCG (rhCG), avoiding any contamination, should replace ehCG. Moreover, a functional evaluation with recombinant human LH (rhLH) would be closer to physiology than a pharmacological testing with hCG.MethodsThe study was conducted in normal men. We first evaluated the dose–effect of ehCG on plasma testosterone and estradiol levels, before and after injection of either hCG or vehicle. Secondly, the responses to the optimal dose of ehCG were compared with those of rhCG. Thirdly, we investigated the dose–effect of rhLH, on steroid hormone secretion. LH, testosterone, and estradiol plasma levels were measured after the injection of either rhLH or placebo.ResultsehCG induced dose-dependent increases in plasma estradiol and testosterone levels. They respectively peaked at 24 and 72 h after the injection. The most potent dose of ehCG (5000 IU) induced results similar to those observed with 250 μg (6500 IU) rhCG. By comparison with placebo, rhLH induced a significant and dose-dependent increase in plasma testosterone levels 4 h after the injection. Peak response of testosterone to rhLH and rhCG was significantly correlated. rhLH did not induce significant change in plasma estradiol level.ConclusionsIn normal men, a single i.v. injection of 150 IU rhLH induces a 25% rise in plasma testosterone levels by comparison with placebo. At the moment, the dynamic evaluation using hCG remains the gold standard test to explore the Leydig cell function. The use of 250 μg rhCG avoiding any contamination should be recommended.

EFFECT OF GLUCOCORTICOIDS ON PLASMA TESTOSTERONE IN MEN

1978 ◽  
Vol 89 (1) ◽  
pp. 126-131 ◽  
Author(s):  
G. Schaison ◽  
F. Durand ◽  
I. Mowszowicz
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Plasma Testosterone ◽  
Acth Stimulation ◽  
Testosterone Levels ◽  
Before And After ◽  
The Mean ◽  
Normal Men ◽  
Lh Secretion ◽  
Dexamethasone Suppression

ABSTRACT ACTH decreases plasma testosterone levels in men. The aim of this study was to assess the part played by the glucocorticoids in this effect, and the mechanism of their action. Plasma androstenedione, testosterone, cortisol and LH were measured in 8 normal men, before and after the following tests: ACTH stimulation (2 mg im), metyrapone administration (500 mg/every 4 h/6 times) and dexamethasone suppression (8 mg/day/3 days). In addition, androstenedione and testosterone were evaluated under human chorionic gonadotrophin (5000 IU HCG/day/3 days) before and after dexamethasone suppression (8 mg/day/6 days). In all patients, ACTH decreased plasma testosterone from 5.87 ± 1.59 (sd) ng/ml to 3.06 ± 0.8 (sd) ng/ml (P < 0.001). In contrast, after metyrapone, the mean plasma testosterone was increased to 6.98 ± 1.75 (sd) ng/ml. This increase, though not statistically significant, was observed in all patients but one. Both tests resulted in a significant increase of plasma androstenedione (P < 0.01 and P < 0.001, respectively). Dexamethasone suppressed both testosterone and androstenedione levels. None of the three tests had a significant effect on the LH concentration. HCG injection increased the mean plasma testosterone to 11.46 ± 2.80 ng/ml. Dexamethasone significantly depressed (P < 0.01) the testosterone response to HCG. These data are consistent with the following conclusions: 1) The decrease of plasma testosterone levels, observed in men after ACTH administration, is not observed after metyrapone induced ACTH increase. This confirms that it is related to cortisol levels rather than to ACTH itself. 2) Glucocorticoids act directly on testicular biosynthesis since they do not induce any change in LH secretion and since dexamethasone reduces testosterone response to HCG.

Forearm mineral content in normal men: Relationship to weight, height and plasma testosterone concentrations

Bone ◽  
1988 ◽  
Vol 9 (5) ◽  
pp. 281-283 ◽  
Author(s):  
A. McElduff ◽  
M. Wilkinson ◽  
P. Ward ◽  
S. Posen
Keyword(s):  
Mineral Content ◽  
Plasma Testosterone ◽  
Normal Men

Integrated Concentration and Circadian Variation of Plasma Testosterone in Normal Men

1973 ◽  
Vol 37 (3) ◽  
pp. 366-371 ◽  
Author(s):  
LUIZ DE LACERDA ◽  
AVINOAM KOWARSKI ◽  
ANN J. JOHANSON ◽  
ROBERT ATHANASIOU ◽  
CLAUDE J. MIGEON
Keyword(s):  
Circadian Variation ◽  
Plasma Testosterone ◽  
Normal Men

The effect of acth administration on plasma testosterone, dihydrotestosterone and serum lh concentrations in normal men

Steroids ◽  
1973 ◽  
Vol 21 (4) ◽  
pp. 553-563 ◽  
Author(s):  
Inese Z. Beitins ◽  
Francis Bayard ◽  
Avinoam Kowarski ◽  
Claude J. Migeon
Keyword(s):  
Plasma Testosterone ◽  
Serum Lh ◽  
Normal Men

Plasma levels of 17-OH-progesterone and testosterone in patients with varicoceles

1983 ◽  
Vol 102 (3) ◽  
pp. 463-469 ◽  
Author(s):  
S. Andò ◽  
C. Giacchetto ◽  
G. Colpi ◽  
M. L. Panno ◽  
E. Beraldi ◽  
...  
Keyword(s):  
Plasma Levels ◽  
Cell Function ◽  
Sperm Count ◽  
Plasma Testosterone ◽  
Seminiferous Tubules ◽  
Significant Difference ◽  
Testosterone Biosynthesis ◽  
Normal Men ◽  
Age Range ◽  
Testicular Steroids

Abstract. In order to study Leydig cell function in patients with varicoceles, we determined plasma levels of the most important testicular steroids, 17-OH-progesterone (17-OH-P) and testosterone (T) in the basal condition and after hCG stimulation. There was a significant inverse linear correlation between age, plasma testosterone, and 17-OH-P (n = 65, r = 0.316, P = 0.01, n = 48, r = 0.532, P = 0.01). This was in contrast to the absence of such correlations in normal men in the same age range. Following hCG stimulation in 16 patients the 17-OH-P/T ratio was significantly increased with respect to normal controls. No correlation was been observed between sperm count and age in varicocele patients. Analysis of variance of 17-OH-P plasma levels between the patients with a sperm count less than 10 million/ml and that of more than 10 million/ml did not reveal any significant difference. These results suggest that the deleterious effects of varicocele on seminiferous tubules and Leydig cells are unrelated. Moreover the increased 17-OH-P/T ratio after hCG stimulation suggests that some enzymatic impairment involving the last steps of testosterone biosynthesis exists in patients with varicoceles. This is evident in middle aged varicocele patients with a premature decrease of plasma levels of testosterone.

scholarly journals Effects of Chronic Sulpiride-Induced Hyperprolactinemia on Plasma Testosterone and Its Responses to hCG in Normal Men

1988 ◽  
Vol 9 (4) ◽  
pp. 231-233 ◽  
Author(s):  
FUMIMARO OSEKO ◽  
NOBUYUKI OKA ◽  
HIROSHI FURUYA ◽  
KEIKO MORIKAWA
Keyword(s):  
Plasma Testosterone ◽  
Normal Men

THE EFFECT OF OESTROGEN ADMINISTRATION ON PLASMA TESTOSTERONE, FSH AND LH LEVELS IN PATIENTS WITH KLINEFELTER'S SYNDROME AND NORMAL MEN

1974 ◽  
Vol 77 (4) ◽  
pp. 765-783 ◽  
Author(s):  
A. G. H. Smals ◽  
P. W. C. Kloppenborg ◽  
R. M. Lequin ◽  
Th. J. Benraad
Keyword(s):  
Normal Subjects ◽  
Plasma Testosterone ◽  
Klinefelter’S Syndrome ◽  
Klinefelter's Syndrome ◽  
Testosterone Levels ◽  
Control Subjects ◽  
Dose Dependent Decrease ◽  
Normal Males ◽  
Normal Men ◽  
Dose Dependent

ABSTRACT In 6 eugonadal males and 6 patients with Klinefelter's syndrome the effect of increasing amounts of ethinyloestradiol (EE) (15, 30 and 150 μg daily for 7 days) on plasma levels of LH, FSH and testosterone was studied. Control levels of LH and FSH in the Klinefelter patients were significantly higher than in the normal males, whereas plasma testosterone levels were significantly lower. In 3 of the 6 Klinefelter patients plasma gonadotrophin levels were clearly elevated despite normal plasma testosterone concentrations. After EE administration a dose-dependent decrease of plasma FSH and testosterone levels was observed in both the control subjects and the Klinefelter patients, whereas the LH decrease was dose-dependent in the Klinefelter patients, but not however, in the eugonadal males. Despite significant testosterone suppression plasma LH and FSH levels in the Klinefelter patients remained supranormal when compared with the levels of the control subjects. Amounts of EE, roughly equivalent to the physiological oestrogen production (15 μg of EE daily) in men, decreased plasma LH and testosterone levels in the normal males, not however, in the Klinefelter patients. The suppression of plasma testosterone by EE in both the normal subjects and the Klinefelter patients could readily be overcome by exogenous gonadotrophin administration, favouring the concept that the EE induced testosterone decrease is predominantly gonadotrophin mediated. It is concluded that small amounts of oestrogens play a role in the pituitary-gonadal axis in normal males. Although higher doses are needed to modulate this axis in Klinefelter's syndrome, the hypothalamic-pituitary-gonadal feedback in this disorder is still operative, though at a higher setting.

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