INFLUENCE OF METYRAPONE ON PLASMA CONCENTRATIONS OF TESTOSTERONE AND ANDROSTENEDIONE IN MAN

1971 ◽  
Vol 68 (3) ◽  
pp. 576-584 ◽  
Author(s):  
K. O. Nilsson ◽  
B. Hökfelt
Keyword(s):  
Body Weight ◽  
Male Patient ◽  
Gradual Increase ◽  
Plasma Concentrations ◽  
Plasma Testosterone ◽  
Testosterone Levels ◽  
Basal Plasma ◽  
Normal Males ◽  
A Minor ◽  
Secondary Hypogonadism

ABSTRACT Metyrapone was administered either orally, 750 mg every four h, in a total of six doses, or intravenously 30 mg per kg body weight as a four h infusion. In three males with normal endocrine functions, metyrapone given orally or intravenously induced a fall in plasma testosterone and an elevation of androstenedione within 2–8 h. When metyrapone was administered to a patient given dexamethasone to suppress endogenous ACTH production, the androstenedione levels did not alter whereas the testosterone levels showed a slight, transient decrease. In two normal females metyrapone administration was followed by a marked increase in plasma androstenedione whereas testosterone showed only a minor, gradual increase. In one male patient with Addison's disease the basal plasma testosterone was normal whereas the level of androstenedione was low. Following metyrapone intravenously, there was a slight suppression of plasma testosterone but no change in the androstenedione concentration. In one patient with primary hypogonadism, two with secondary hypogonadism and two with Klinefelter's syndrome the plasma testosterone was low under basal conditions and did not change following metyrapone. Basal plasma androstenedione was within the range for normal males and increased markedly following metyrapone in all the cases.

THE EFFECT OF SHORT AND LONG TERM HUMAN CHORIONIC GONADOTROPHIN (HCG) ADMINISTRATION ON PLASMA TESTOSTERONE LEVELS IN KLINEFELTER'S SYNDROME

1974 ◽  
Vol 77 (4) ◽  
pp. 753-764 ◽  
Author(s):  
A. G. H. Smals ◽  
P. W. C. Kloppenborg ◽  
Th. J. Benraad
Keyword(s):  
Plasma Testosterone ◽  
Klinefelter’S Syndrome ◽  
Klinefelter's Syndrome ◽  
Absolute Increase ◽  
Testosterone Levels ◽  
Basal Plasma ◽  
Patient Groups ◽  
Pre Treatment ◽  
Secondary Hypogonadism

ABSTRACT The effect of acute (1500 IU/day for 3 days) and chronic HCG administration (1500 IU, 3 times weekly) on plasma testosterone levels in patients with Klinefelter's syndrome was compared with the response observed in patients with hypogonadotrophic eunuchoidism and in eugonadal male controls. Basal plasma testosterone levels in the Klinefelter patients were significantly lower than in the control subjects and significantly higher than in the patients with secondary hypogonadism. In all but one Klinefelter patient the plasma LH levels were markedly elevated even in the presence of normal testosterone levels. No significant correlation could be demonstrated between the plasma testosterone concentrations and the LH levels in the Klinefelter patients. Short term HCG administration resulted in a significant increase in the plasma testosterone levels in each of the 3 groups studied, independent of the basal value. The absolute increase in the Klinefelter patients was quantitatively comparable to that in the patients with secondary hypogonadism, but significantly lower than in the eugonadal controls. During long term HCG treatment the plasma testosterone levels definitely increased in both patient groups, but remarkably in the Klinefelter patients testosterone levels tended to decrease on continuing treatment, though in most patients testosterone levels remained higher than the pre-treatment values. The data on the effect of acute and chronic HCG administration on plasma testosterone levels in this study illustrate again that Leydig cells in Klinefelter's syndrome still retain a functional reserve, though less than in eugonadal males.

EFFECTS OF AN INTRAVENOUS INJECTION OF TETRACOSACTID ON PLASMA CORTICOSTEROID AND TESTOSTERONE LEVELS IN UNSTRESSED MALE RABBITS

1979 ◽  
Vol 91 (3) ◽  
pp. 511-518 ◽  
Author(s):  
K. W. Faulborn ◽  
M. Fenske ◽  
L. Pitzel ◽  
A. König
Keyword(s):  
Body Weight ◽  
Intravenous Injection ◽  
Plasma Levels ◽  
Plasma Testosterone ◽  
Rapid Rise ◽  
Testosterone Concentration ◽  
Testosterone Levels ◽  
Blood Withdrawal ◽  
Basal Plasma ◽  
Pre Treatment

ABSTRACT Administration of tetracosactid into male rabbits, fitted with permanently indwelling jugular catheters, resulted in a rapid rise of plasma corticosteroids and plasma testosterone. Corticosteroid concentrations were significantly elevated at 40 and 60 min and testosterone concentrations 20 min after the iv injection of tetracosactid (2.5, 5.0, and 10.0 μg/kg body weight), in comparison to pre-treatment levels. Corticosteroid values in plasma were elevated as long as 120 min after tetracosactid injection. In contrast, testosterone levels were lower at 60–120 min after tetracosactid injection than corresponding pre-treatment values. However, these differences were not significant. At the doses used no tetracosactiddose-dependent corticosteroid or testosterone release could be found; apparently, testosterone release is only dependent upon basal plasma levels but not upon the dose of tetracosactid applied. From these studies it is concluded that tetracosactid may bring about an increase or decrease of testosterone concentration in plasma in the buck depending upon the length of time elapsing between injection of tetracosactid and blood withdrawal.

BODY PROPORTIONS AND ANDROGENICITY IN RELATION TO PLASMA TESTOSTERONE LEVELS IN KLINEFELTER'S SYNDROME

1974 ◽  
Vol 77 (2) ◽  
pp. 387-400 ◽  
Author(s):  
A. G. H. Smals ◽  
P. W. C. Kloppenborg ◽  
T. J. Benraad
Keyword(s):  
Upper Body ◽  
Clinical State ◽  
Plasma Testosterone ◽  
Klinefelter’S Syndrome ◽  
Body Segment ◽  
Klinefelter's Syndrome ◽  
Testosterone Levels ◽  
Arm Span ◽  
Basal Plasma ◽  
Low Testosterone

ABSTRACT Basal plasma testosterone levels (mean ± sd 290 ± 141 ng/100 ml) (range 72–684 ng/100 ml) in 25 chromatin positive patients with Klinefelter's syndrome (23 XXY, 1 XXYY, 1 XY/XXY) were significantly lower than in 25 age matched controls (mean ± sd 603 ± 169 ng/100 ml). In 11 out of the 25 Klinefelter patients however, plasma testosterone levels were in the normal range and these patients differed significantly from the patients with low testosterone levels with respect to the clinical state of androgenicity. In the group of Klinefelter patients, but not in the controls, a significant negative correlationship was found between plasma testosterone levels and each of the variables: body weight, arm span, length of the lower body segment and the ratio's lower/upper and span/upper body segment.

Possible role of prolactin in the inhibitory effect of testosterone on the hypothalamic-pituitary-testicular axis in the rat

1985 ◽  
Vol 105 (3) ◽  
pp. 423-427 ◽  
Author(s):  
J. A. F. Tresguerres ◽  
L. F. Perez Mendez ◽  
A. Lopez-Calderon ◽  
A. I. Esquifino
Keyword(s):  
Inhibitory Effect ◽  
Plasma Testosterone ◽  
Plasma Prolactin ◽  
Intact Male ◽  
Testosterone Levels ◽  
Basal Plasma ◽  
Male Wistar Rats ◽  
Lh Releasing Hormone ◽  
Acute And Chronic Treatments

ABSTRACT To study the role of testosterone on the regulation of the hypothalamic-pituitary-testicular axis, young intact male Wistar rats were given acute (24 h) or chronic (5 days) subcutaneous treatments of 500 μg testosterone propionate (TP) or vehicle alone. Plasma LH, prolactin and testosterone levels were measured both basally and after administration of LH-releasing hormone (LHRH) or human chorionic gonadotrophin (hCG) by means of specific radioimmunoassay systems using materials supplied by the NIADDK. After acute treatment with TP there was an increase in basal plasma testosterone concentrations and no modification in the hCG response when compared with vehicle-treated animals. No difference could be detected in basal plasma testosterone levels after the chronic treatment, but a significant reduction in the hCG response was observed. Both acute and chronic treatments with TP resulted in a significant decrease of basal plasma LH levels. A reduced LH response to LHRH in acutely treated rats and no response in the chronically treated rats was detected. Plasma prolactin levels showed an increase after both acute and chronic treatments. To evaluate the possible role of the increased plasma prolactin levels on the above modifications during TP treatment, another group of animals was treated with TP and bromocriptine (dopamine agonist) simultaneously to avoid the increase in plasma prolactin levels. In this situation, neither basal plasma LH levels nor the response to LHRH were altered when compared to vehicle-treated rats; a normal testosterone response to hCG stimulation was observed in spite of the high basal plasma testosterone levels. All these observations suggest that increased prolactin levels may exert a modulatory role on the negative feedback effect of testosterone both at the testicular and central levels. J. Endocr. (1985) 105, 423–427

CORRELATION OF PITUITARY AND TESTICULAR RESPONSES TO STIMULATION TESTS IN CRYPTORCHID CHILDREN

1977 ◽  
Vol 86 (3) ◽  
pp. 641-650 ◽  
Author(s):  
Dominique Gendrel ◽  
Marc Roger ◽  
Jean-Louis Chaussain ◽  
Pierre Canlorbe ◽  
Jean-Claude Job
Keyword(s):  
Leydig Cells ◽  
Significant Positive Correlation ◽  
Plasma Testosterone ◽  
Early Puberty ◽  
Testosterone Levels ◽  
Short Course ◽  
Basal Plasma ◽  
Stimulation Tests ◽  
Lh Rh ◽  
Lh Secretion

ABSTRACT LH-RH test and HCG stimulation test were performed in 154 cryptorchid boys aged 1 month to 15 years (64 unilateral and 90 bilateral). Basal plasma LH levels and LH response to LH-RH were significantly lower from infancy to early puberty in cryptorchids compared with controls. Basal FSH levels and FSH response to LH-RH were normal. The post-HCG rise of plasma testosterone was reduced until mid-puberty. A significant positive correlation was found between post-HCG testosterone levels and pre- and post-LH-RH levels of LH. This correlation suggests that testicular maldescent and the decreased ability of Leydig cells to respond to a short course of HCG may result from an early defect or a delay of pituitary LH secretion.

DEVELOPMENTAL PATTERNS OF PLASMA AND TESTICULAR TESTOSTERONE IN MICE FROM BIRTH TO ADULTHOOD

1978 ◽  
Vol 89 (4) ◽  
pp. 780-788 ◽  
Author(s):  
Ch. Jean-Faucher ◽  
M. Berger ◽  
M. de Turckheim ◽  
G. Veyssiere ◽  
Cl. Jean
Keyword(s):  
Body Weight ◽  
Seminal Vesicle ◽  
Sex Difference ◽  
Plasma Testosterone ◽  
Male Mice ◽  
Developmental Patterns ◽  
Testosterone Levels

ABSTRACT Male mice were raised in cohabitation with females from birth to 90 days. Testosterone was measured every 10 days in plasma and testes. Sex difference in body weight was related to the pre-pubertal increase of testosterone levels in males. The weight of the seminal vesicle was positively correlated with circulating testosterone levels between 1 and 40 days but not between 50 and 90 days Testosterone concentrations in the plasma and testes were high at birth: 630 pg/ml and 58.0 ± 17.7 ng/100 mg; they subsequently decreased during the first days of life and remained low until day 20: 240 ± 110 pg/ml and 0.1 ± 0.03 ng/100 mg. The testosterone levels then increased rapidly between days 20 and 30 and especially between 30 and 40 reaching their maxima: 5770 ± 1720 pg/ml and 123.7 ± 18.3 ng/100 mg testis. This increase was transitory and testosterone levels fell after day 40. By 90 days, the testosterone levels, 440 ± 65 pg/ml and 43.2 ± 5.5 ng/100 mg testis, were comparable to those measured at birth. Plasma testosterone and age were positively correlated between 1 and 40 days, and negatively between 50 and 90 days. The first fertile matings occurred at age 40 days.

PLASMA LH AND FSH RESPONSE TO LRH AND PLASMA TESTOSTERONE LEVELS IN BOYS WITH IRREGULAR PUBERTY

1977 ◽  
Vol 85 (3) ◽  
pp. 456-464 ◽  
Author(s):  
Zvi Dickerman ◽  
Yehuda Bar-Haim ◽  
Ruth Prager-Lewin ◽  
Haiuta Kaufman ◽  
Zvi Laron
Keyword(s):  
Bone Age ◽  
Pubic Hair ◽  
Growth Spurt ◽  
Plasma Testosterone ◽  
Control Group ◽  
Testicular Development ◽  
Pubertal Stage ◽  
Testosterone Levels ◽  
Basal Plasma ◽  
Pubertal Stages

ABSTRACT Nineteen boys with irregular puberty (IP), defined as a discrepancy of two or more pubertal stages between the criteria for genitalia and that for pubic hair, were subjected to a standard LRH test (50 μg/m2, iv) and the response of gonadotrophins as well as the basal levels of plasma testosterone, LH and FSH were compared to those of boys with normal, regular puberty. When the results were plotted against the pubertal stage for genitalia (Pg), it was found that in the boys with IP the basal plasma testosterone levels were lower and the response of plasma LH to LRH stimulation lesser than in the controls. However, when these parameters were plotted against the pubertal stage for pubic hair (Ph) it was found, that in the boys with IP the plasma testosterone levels were significantly higher and the response of both LH and FSH stimulation greater than in the control group. It was concluded that irregular puberty in boys may be regarded as a normal variation. The delayed development of sexual hair and penile length, and retarded pubertal growth spurt and bone age maturation seen in these boys, with normal testicular development, may be explained by a temporary reduced peripheral sensitivity to androgens and a compensatory effort by the pituitary, manifested in increased secretion of LH and testosterone, relatively to their pubertal stage for pubic hair.

PLASMA TESTOSTERONE IN KLINEFELTER'S SYNDROME: DIURNAL VARIATION AND RESPONSE TO ACTH AND DEXAMETHASONE

1975 ◽  
Vol 78 (3) ◽  
pp. 604-612 ◽  
Author(s):  
A. G. H. Smals ◽  
P. W. C. Kloppenborg ◽  
T. J. Benraad
Keyword(s):  
Plasma Testosterone ◽  
Klinefelter’S Syndrome ◽  
Klinefelter's Syndrome ◽  
Normal Range ◽  
Short Term ◽  
Plasma Testosterone Level ◽  
Testosterone Levels ◽  
Basal Plasma ◽  
Order Of Magnitude ◽  
The Mean

ABSTRACT The mean basal plasma testosterone level in 28 patients with chromatin positive Klinefelter's syndrome was significantly lower than in 58 healthy male controls. In 12 of the patients the hormone levels were in the normal range. In both the eugonadal males and the Klinefelter patients the plasma testosterone levels spontaneously decreased throughout the day, the relative decrease in both groups being of the same order of magnitude. Short term ACTH infusion and the administration of dexamethasone did not significantly influence the plasma testosterone concentration in the Klinefelter patients. These findings do not support the view that the adrenal cortex plays a major role in contributing to the circulating plasma testosterone levels in this syndrome.

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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