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.

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.

SHORT-TERM EFFECTS OF COPULATION, HUMAN CHORIONIC GONADOTROPHIN INJECTION AND NON-TACTILE ASSOCIATION WITH A FEMALE ON TESTOSTERONE LEVELS IN THE MALE RAT

1974 ◽  
Vol 60 (3) ◽  
pp. 429-439 ◽  
Author(s):  
K. PURVIS ◽  
N. B. HAYNES
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Physical Contact ◽  
Male Rats ◽  
Male Rat ◽  
Plasma Testosterone ◽  
Short Term ◽  
Testosterone Levels ◽  
Peripheral Plasma ◽  
First Contact

SUMMARY Peripheral plasma testosterone levels in the male rat were increased above control levels 5 min after the first intromission with an oestrous female, or 8–10 min after first contact with the female. The levels remained raised for at least 30 min if copulation was allowed to continue. Intravenous injection of human chorionic gonadotrophin resulted in an increased peripheral concentration of plasma testosterone after 10–15 min and an increase of testosterone content of the testis 5–10 min after injection, indicating that the rat testis has a potential to respond rapidly to gonadotrophin. The results suggested that if the testosterone surge during copulation was gonadotrophin-dependent, it was initiated before the first intromission. Indeed, plasma testosterone levels were raised in male rats 5 min after being placed in the proximity of oestrous females but not allowed physical contact.

EFFECT OF AN ANABOLIC STEROID (METANDIENON) ON PLASMA LH, FSH, AND TESTOSTERONE AND ON THE RESPONSE TO INTRAVENOUS ADMINISTRATION OF LRH

1976 ◽  
Vol 83 (4) ◽  
pp. 856-864 ◽  
Author(s):  
Pentti Holma ◽  
Herman Adlercreutz
Keyword(s):  
Luteinizing Hormone ◽  
Intravenous Administration ◽  
Anabolic Steroid ◽  
Plasma Levels ◽  
Oral Intake ◽  
Plasma Testosterone ◽  
Before And After ◽  
The Mean ◽  
Pre Treatment ◽  
Lh Secretion

ABSTRACT Plasma levels of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) as well as the response of LH and FSH to the intravenous administration of 100 μg of luteinizing hormone releasing hormone (LRH) were measured in 16 well-trained athletes (mean age 30 years) before and after 2 months of daily oral intake of 15 mg of metandienon, an anabolic steroid (Anabolin®, 17α-methyl-17β-hydroxy-1,4-androstadien-3-one, Medica, Finland). All athletes continued to train regularly, just as they had done for several years. During administration of metandienon the mean plasma testosterone level fell 69%, from 29.4 ± 11.6 nmol/l to 9.1 ± 7.5 nmol/l. The mean plasma levels of LH and FSH also fell significantly (P < 0.001 and P < 0.01, respectively), both about 50%. Because LH and FSH levels were low after administration of the steroid the maximum stimulation values after LRH administration were also lower than pre-treatment values although the mean increments did not differ significantly before and after administration of the anabolic steroid. However, after treatment, the FSH response curve had a biphasic pattern in most subjects, with peaks at 10 to 20 and 50 to 60 min after the iv injection of LRH. Administration of LRH after the treatment period had no effect on FSH secretion in two subjects and no effect on LH secretion in one. Our results show that administration of an anabolic steroid causes a pronounced lowering of plasma levels of testosterone, LH and FSH but causes no gross alteration in the response of LH secretion to stimulation by LRH. The reason for the biphasic response pattern of FSH to LRH administration in most subjects is not known.

Effect of intraventricular injection of 5,6-dihydroxytryptamine on spermatogenesis and plasma testosterone levels in the rat

1985 ◽  
Vol 106 (3) ◽  
pp. 395-NP ◽  
Author(s):  
T. K. Das ◽  
R. Mazumder ◽  
N. M. Biswas
Keyword(s):  
Quantitative Evaluation ◽  
Wistar Rats ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Seminiferous Epithelium ◽  
Intraventricular Injection ◽  
Plasma Testosterone ◽  
Testosterone Levels ◽  
Testicular Steroidogenesis

ABSTRACT Quantitative evaluation of spermatogenesis at stage VII of the cycle of the seminiferous epithelium and radioimmunoassay of plasma testosterone were performed in adult Wistar rats after intraventricular injection of 5,6-dihydroxytryptamine (5,6-DHT). The rats were killed 2, 10 and 21 days after injection. Brain 5-hydroxytryptamine (5-HT) and plasma testosterone levels were found to be significantly lower in all rats treated with 5,6-DHT. A significant reduction in step 7 spermatid count was also observed after 10 and 21 days. Supplementation with human chorionic gonadotrophin for 21 days in rats injected with 5,6-DHT partially prevented the step 7 spermatid degeneration and increased testosterone levels without producing any effect on brain concentrations of 5-HT. These results suggest that changes in testicular steroidogenesis and spermatogenesis are secondary to pituitary gonadotrophin release which, in turn, is under the influence of brain 5-HT neurones. J. Endocr. (1985) 106, 395–400

METABOLISM OF EXOGENOUS HUMAN CHORIONIC GONADOTROPHIN IN MEN

1979 ◽  
Vol 80 (1) ◽  
pp. 83-89 ◽  
Author(s):  
J. R. SOWERS ◽  
A. E. PEKARY ◽  
J. M. HERSHMAN ◽  
M. KANTER ◽  
J. J. DISTEFANO
Keyword(s):  
Renal Clearance ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Commercial Preparation ◽  
Exclusion Chromatography ◽  
Biological Potency ◽  
The Mean ◽  
Β Hcg ◽  
Normal Men ◽  
Higher Doses

The immunoreactivity of a commercial preparation of human chorionic gonadotrophin (HCG) was determined in a homologous double antibody radioimmunoassay for HCG using antisera to the β-subunit of the hormone. The immunoreactivity of the commercial HCG was found to be 2·2 ± 0·3 (mean ± 2 s.d.) times the biological potency. Exclusion chromatography of the commercial HCG and then curve resolution of the elution profile derived from the radioimmunoassay revealed that on a molar basis, 21% of the immunoreactivity was attributable to β-HCG. The rate of clearance of this preparation of HCG from the plasma after intravenous administration was determined as a function of the dose administered to ten normal men (age 36–64 years). The doses ranged from 10 000 to 300 000 i.u. immunological potency. The rate of clearance decreased significantly (r = 0·574, P< 0·05) with increasing doses of HCG from a mean of 786 ml/h at the lowest dose to a mean of 298 ml/h at the highest dose. The renal clearance of administered HCG also decreased with increasing doses; the mean renal clearance of the 10 000 i.u. dose was 3·6 times the mean renal clearance after administration of 200 000 i.u. When the accumulated urinary HCG was expressed as a percentage of the dose administered, 14·1% of the 10 000 i.u. dose and 9·8% of the higher doses accumulated in the urine, suggesting that non-renal clearance increased with increasing dose.

THE EFFECT OF MESTEROLONE ADMINISTRATION TO NORMAL MEN ON THE PITUITARY-TESTICULAR FUNCTION

1974 ◽  
Vol 77 (2) ◽  
pp. 380-386 ◽  
Author(s):  
A. Aakvaag ◽  
S. B. Strømme
Keyword(s):  
Protein Binding ◽  
Testosterone Level ◽  
Plasma Levels ◽  
Mean Value ◽  
Plasma Testosterone ◽  
Testicular Function ◽  
Plasma Testosterone Level ◽  
Before And After ◽  
The Mean ◽  
Normal Men

ABSTRACT Mesterolone (1α-methyl-5α-dihydrotestosterone) has been given to 10 normal men, age 24–27 years, and the effect on the plasma levels of ICSH, FSH and testosterone has been studied. No effect on the plasma levels of ICSH and FSH could be detected. After 4 weeks on 75 mg mesterolone per day a significant (P < 0.01) drop in the mean value for plasma testosterone level was observed, 5.2 to 4.0 ng/ml. After another 4 weeks on 150 mg mesterolone per day a further decrease to 3.5 ng/ml was found. During mesterolone administration the protein binding of testosterone in plasma was significantly reduced, and it appeared that the level of free (non-protein bound) testosterone in diluted plasma remained unchanged, 0.37 and 0.41 ng/ml, before and after mesterolone administration respectively. The results suggest that mesterolone given in doses of 75 and 150 mg/day to normal men does not suppress the pituitary ICSH production or the testicular testosterone production.

EVIDENCE FOR THE ADRENAL SOURCE OF ANDROGENS IN PRECOCIOUS ADRENARCHE

1976 ◽  
Vol 82 (2) ◽  
pp. 342-352 ◽  
Author(s):  
Sigrun Korth-Schutz ◽  
Lenore S. Levine ◽  
Maria I. New ◽  
Diane M. Chow
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Acth Stimulation ◽  
Prepubertal Children ◽  
Precocious Adrenarche ◽  
Serum Androgens ◽  
Dexamethasone Suppression

ABSTRACT In order to determine the source of androgens in precocious adrenarche, serum androgens were determined in 8 girls with precocious adrenarche and 5 agonadal children in adrenarche under conditions of adrenal and gonadal stimulation and suppression. All androgens increased with ACTH stimulation in both groups. Stimulability of serum androgens in girls with precocious adrenarche with ACTH was more consistent than in 13 prepubertal children. Human chorionic gonadotrophin administration increased serum Δ4-androstenedione, testosterone and dihydrotestosterone in the girls with precocious adrenarche but not in the agonadal children, demonstrating the failure of HCG to stimulate adrenals. Dexamethasone suppression decreased levels of all androgens in both groups, whereas Norlutin® or Ovral® produced variable changes. These studies support the adrenal origin of androgens in precocious adrenarche and the lack of ovarian contributions in this condition.

INHIBITION BY MELATONIN OF THE PITUITARY RESPONSE TO LUTEINIZING HORMONE RELEASING HORMONE IN VIVO

1978 ◽  
Vol 76 (3) ◽  
pp. 487-491 ◽  
Author(s):  
K. YAMASHITA ◽  
M. MIENO ◽  
T. SHIMIZU ◽  
ER. YAMASHITA
Keyword(s):  
Luteinizing Hormone ◽  
Carotid Artery ◽  
Anterior Pituitary ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Luteinizing Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Lh Rh ◽  
Lh Secretion

The rate of secretion of 17-oxosteroids by the testes of anaesthetized dogs in vivo was used as an index of LH secretion. Intracarotid injection of luteinizing hormone releasing hormone (LH-RH, 1, 5 or 10 μg/kg body wt) resulted in an increase in the testicular 17-oxosteroid secretion which was roughly proportional to the dose administered and which reached a maximum 60 min after the injection. Testicular output of 17-oxosteroids was unaffected by administration of melatonin (10 or 100 μg/kg body wt) into the carotid artery. When LH-RH (5 μg/kg) was injected into the carotid artery 3 h after intracarotid injection of melatonin (10 or 100 μg/kg), the testicular response to LH-RH was considerably diminished. Pretreatment with melatonin (100 μg/kg) did not alter the testicular response to human chorionic gonadotrophin (20 i.u./kg body wt) given i.v. It is concluded that melatonin may act directly on the anterior pituitary gland in dogs to inhibit the LH-RH-induced release of LH.

scholarly journals Testosterone Response of Cryptorchid and Hypophysectomized Rats to Human Chorionic Gonadotrophin (hCG) Stimulation

1985 ◽  
Vol 38 (4) ◽  
pp. 445 ◽  
Author(s):  
Y M Hodgson ◽  
DM de Kretser
Keyword(s):  
Single Injection ◽  
Serum Testosterone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Testosterone Levels ◽  
Hypophysectomized Rats ◽  
Secondary Rise

The testosterone responses to a single injection of HCG (100 i.u.) in hypophysectomized (hypox.), cryptorchid or sham-operated rats were followed over a 5-day period. In sham-operated rats, hCG induced a biphasic rise in serum testosterone, peaks being observed at 2 and 72 h. Reduced testis weights, elevated FSH and LH levels and reduced serum testosterone levels were found after 4 weeks of cryptorchidism, but hCG stimulation resulted in a normal 2 h peak in serum testosterone. However, the secondary rise at 72 h in cryptorchid rats was significantly lower than sham-operated rats.

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