Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Testosterone was estimated by radioimmunoassay in molar vesicle fluid in 41 patients and theca-lutein cyst fluid in three patients with hydatidiform moles. The testosterone concentration in the molar vesicle fluid ranged from 0.4 ng/ml to 28.1 ng/ml with a mean+/-SEM of 6.0+/-1.0 ng/ml while in the theca-lutein cyst fluid, it ranged from 4.7 ng/ml to 23.5 ng/ml. Oestradiol-17beta and human chorionic gonadotrophin (HCG) were also estimated in the molar vesicle fluid. The oestradiol-17beta concentration ranged from 0.1 ng/ml to 26.2 ng/ml with a mean+/-SEM of 10.7+/-1.1 ng/ml. HCG concentration ranged from 18 000 to 150 000 mIU/ml with a mean+/-SEM of 49 800+/-5 000 mIU/ml. A positive correlation was found between testosterone and oestradiol-17beta (r = +0.37; P less than 0.01) but not between testosterone and HCG (r = 0.32; 0.1 greater than P greater than 0.05). Our findings suggest that molar trophoblast is the major source of testosterone.
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PMID:Testosterone in the molar vesicle fluid and theca-lutein cyst fluid. 62 2

The short-term metabolic effects of testosterone treatment on circulating levels of 1,25-dihydroxyvitamin D and insulin-like growth factor-I (IGF-I) were studied in 13 hypogonadal men. The study group included 11 men with Klinefelter's syndrome, with varying degree of androgen deficiency, and two men with secondary hypogonadism. Pretreatment levels of 1,25-dihydroxyvitamin D, vitamin D-binding protein and IGF-binding protein-I were all within the normal range. The levels of IGF-I were lower than normal in 5/11 of the Klinefelter patients and in one patient with GH-deficiency. Testosterone treatment increased circulating total 1,25-dihydroxyvitamin D significantly from 75 +/- 4 pmol l-1 (mean +/- SEM) to 86 +/- 4 (P less than 0.01) and the free 1,25-dihydroxyvitamin D-index from 1.95 +/- 0.11 to 2.39 +/- 0.12 (P less than 0.01). Serum levels of IGF-I increased from 117 +/- 22 micrograms/l to 143 +/- 23 (P less than 0.01) during androgen treatment. No significant effects on levels of IGF-binding protein-I were seen. It is concluded that androgen therapy increases the availability of 1,25-dihydroxyvitamin D and the level of IGF-I, which may be important links in the action of testosterone.
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PMID:Testosterone increases serum 1,25-dihydroxyvitamin D and insulin-like growth factor-I in hypogonadal men. 157 32

To determine the relationship between increasing luteinizing hormone (LH) production and the diurnal secretion of LH and testosterone (T) in adult men, studies were performed on five men with gonadotropin insufficiency associated with prolactinoma, five eugonadal men, and five men with primary testicular failure. Blood samples were drawn every 10 to 20 minutes for 24 hours beginning at 8:00 to 8:30 AM to evaluate diurnal periodicity. Mean (+/- SEM) LH levels in the three groups were 7.67 +/- 1.46 mlU/ml, 13.9 +/- 3.2 mlU/ml, and 62.3 +/- 14.4 mlU/ml, respectively, and mean serum T levels were 8.05 +/- 1.49 nmol/L, 13.9 +/- 3.5 nmol/L, and 9.15 +/- 1.3 nmol/L, respectively. Cosinor analysis revealed that each hyperprolactinemic man had a T rhythm with a significant 24-hour periodicity; the mean acrophase was at 5:00 AM. Testosterone levels were 35.0 +/- 10.6% less at 4:00 PM than at 8:00 AM. Eugonadal men also demonstrated a significant diurnal T rhythm with an acrophase at 6:00 AM, and T levels were 15.8 +/- 5.3% less at 4:00 PM than at 8:00 AM. By contrast, there was no significant diurnal rhythm in T secretion among the men with testicular failure, although serum T levels were 11.5 +/- 3.7% less at 4:00 PM than at 8:00 AM. For LH, hyperprolactinemic men demonstrated a significant 24-hour rhythm with an acrophase at 1:30 AM, whereas no significant 24-hour periodicity was identified among either eugonadal men or men with testicular failure.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Diurnal rhythm of testosterone and luteinizing hormone in hypogonadal men. 191 82

The suppressive effect of the gonadotropin-releasing hormone (GnRH) antagonist Nal-Glu ([Ac-D2Nal1, D4ClPhe2, D3Pal3, Arg5, D-4-p-methoxybenzoyl-2-aminobutyric acid6, DAla10]-GnRH), injected intramuscularly with 5 mg, was studied in six men. Testosterone decreased by 87 +/- 2.3%, whereas the mean drops were 50 +/- 10%, 43 +/- 6.6%, and 39 +/- 5.6% for radioimmunoassayable luteinizing hormone (LH), follicle-stimulating hormone, and free alpha-subunit, respectively (mean +/- SEM). Immunological characteristics of plasma LH were modified during the inhibition and recovery phases as evidenced by comparison between polyclonal and monoclonal assays. In two additional subjects sampled every 10 minutes, both LH and alpha-subunit pulses were suppressed by NalGlu injection and restored by pulsatile GnRH infusion. However, a nonpulsatile and possibly non-GnRH-dependent alpha-subunit secretion was maintained after NalGlu administration.
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PMID:Changes in gonadotropin and alpha-subunit secretion after a single administration of gonadotropin-releasing hormone antagonist in adult males. 211 79

Breast cyst fluids from 118 women, aged 29 to 69 years, were analyzed by radioimmunoassays for beta-human chorionic gonadotropin (beta-hCG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), and thyroid-stimulating hormone (TSH). Blood was drawn at the same time in many cases to compare hormonal levels in serum with those in the breast cyst fluids (BCF). The levels of beta-hCG in BCF were relatively high, with a mean (+/- standard error of the mean [SEM]) of 58.9 +/- 16.8 mIU/ml; serum levels of beta-hCG were negligible. LH and TSH also were elevated in BCF compared with serum levels, exhibiting mean values (+/- SEM) of 26.7 +/- 4.3 mIU/ml and 6.4 +/- 0.44 muIU/ml, respectively. The levels of FSH and PRL in BCF were equivalent to the levels in the serum. The presence of biologically active hCG was suggested in several BCF samples using the rat ovarian hyperemia test. Samples of BCF were assessed for the capacity to stimulate Leydig cell testosterone production in vitro in the presence or absence of an anti-hLH antiserum. Testosterone production was significantly (P less than 0.05) enhanced, even in the presence of the antiserum. These data suggest that BCF contains biologically active hCG.
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PMID:Fibrocystic breast disease: the significance of beta-human chorionic gonadotropin and other polypeptides in breast cyst fluid. 245 Jul 89

There is evidence that the capacity to synthesize gonadotropins is less in teenage boys with gonadotropin deficiency (GD) than in those with constitutional delay of puberty (DP). We hypothesized that this might predispose the latter group to have a greater pituitary-testicular response to the potent long-acting GnRH agonist nafarelin. We evaluated GD patients 14.3-24.0 yr of age (n = 8) and prepubertal DP boys 14.8-17.6 yr of age (n = 3). In most subjects the response to nafarelin was compared to that of frequent nocturnal blood sampling for LH and testosterone levels. All subjects received a single dose of nafarelin (1.0 micrograms/kg, sc), and blood was then sampled at 0.5- to 4.0-h intervals for 24 h. Patients with GD could not be distinguished from those with DP by pubertal staging criteria or by baseline values of LH, FSH, or testosterone. Patients with GD exhibited no rise in plasma LH levels during sleep, in contrast to those with DP. All GD patients had LH and FSH responses distinctly less than those of the DP group between 3-24 h postnafarelin. The peak incremental responses of GD and DP to nafarelin were, respectively: LH, 5.5 +/- 2 3 (+/- SEM and 77.2 +/- 8.6 IU/L (P less than 0.02); FSH, 2.7 +/- 1.2 and 9.4 +/- 0.8 IU/L (P less than 0.005). Testosterone peak responses were lower as well (0.26 +/- 0.2 vs 1.6 +/- 0.5 nmol/L, P = 0.05). This pilot study suggests that the response to a single test dose of nafarelin distinguishes GD from DP in the teenage years as well as does measurement of nocturnal LH levels. The testosterone response to the GnRH agonist adds a new dimension to GnRH testing. Nafarelin also allows assessment of the bioactivity of endogenous gonadotropin, is a more potent stimulus of pituitary-testicular function than endogenous GnRH secretion, and is more cost-effective than nocturnal sampling.
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PMID:A new test of combined pituitary-testicular function using the gonadotropin-releasing hormone agonist nafarelin in the differentiation of gonadotropin deficiency from delayed puberty: pilot studies. 252 66

In the present study we investigated in adult male rats the effects of castration on Dehydroepiandrosterone (DHEA), Androstenedione (delta 4), Testosterone (T) and Dihydrotestosterone (DHT) plasma levels: five days (group II), seven weeks (group III) and eleven weeks (group IV) after orchiectomy. The same hormone assays were performed in rats approximately 60 days of age which underwent a sham-operation for orchiectomy (group I). Our data show that five days following orchiectomy (group II) delta 4, T and DHT were decreased with respect to sham-operated rats. (Group I: delta 4: 83.3 +/- 14.9 (SEM) ng/dl (n = 12); T: 435.32 +/- 51.45 (n = 12); DHT: 51.47 +/- 6.54 (n = 12); Group II: delta 4: 44.81 +/- 6.09 (n = 12) P = 0.05; T: 25.54 +/- 2.88 (n = 12) P less than 0.01; DHT: 12.9 +/- 2.51 (n = 12) P less than 0.01). Seven weeks afterwards T and DHT remained significantly lower (group III: T: 54.37 +/- 12.21, n = 16) (P less than 0.01; DHT: 33.22 +/- 4.49 (n = 16) P less than 0.01) while eleven weeks after all steroids were significantly decreased with respect to the values observed in sham-operated rats. (Group IV) delta 4: 32.01 +/- 5.7 (n = 10) P less than 0.01: T: 27.29 +/- 7.05 (n = 10) P less than 0.01; DHT: 29.03: 5.34 (n = 10) P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Physiological changes in androgen plasma levels with elapsing of time from castration in adult male rats. 296 41

Transient hypogonadotrophic hypogonadism commonly occurs after major medical insults. Because data on testosterone precursors are sparse and because little is known about the aetiology of these changes, we studied the interactions of traumatic brain injury with gonadal steroidogenesis and with sympathetic nervous system activation. Patients were divided into two groups based upon the severity of neurological dysfunction using the Glasgow Coma Score (GCS); Group 1 less than 8, Group 2 greater than or equal to 8. Group 1 was further divided into those patients treated (Group 1b) and those not treated with dexamethasone (Group 1a). Plasma levels of testosterone, androstenedione, 17-hydroxyprogesterone, DHEA sulphate, cortisol, LH, FSH, and the catecholamines noradrenaline (NE), adrenaline (EPI) and dopamine were measured in 31 acutely brain injured men, aged 18-95, shortly after their accident and 4 days later. In all patients, NE and EPI were elevated on admission (NE: 841 +/- 105 (SEM) pg/ml; EPI: 191 +/- 32 pg/ml and there were highly significant inverse correlations between admission NE (r = -0.52, P less than 0.003) and EPI (r = 0.44, P less than 0.02) levels and day 4 testosterone concentrations. Testosterone fell 53% (P less than 0.001) in 13 Group 1a men, but only 25% (P = NS) in the less severely injured. Similar reductions occurred in cortisol and the steroid precursors. However, only testosterone, 17-hydroxyprogesterone, and DHEA sulphate levels were significantly lower than normal on day 4. LH and FSH levels were also significantly reduced from elevated admission levels. In the eight men treated with dexamethasone (8-40 mg/ml) (Group 1b), the decrease in testosterone, LH and FSH concentrations were similar to those present in Group 1a. Thus, severe traumatic brain injury leads to hypogonadotrophic hypogonadism which affects testosterone and its precursors. The magnitude of the hormonal dysfunction is dependent upon the severity of the neurological insult. Finally, the decrease in testosterone is significantly correlated with admission catecholamine levels, which may suggest a role for the sympathetic nervous system (SNS) in mediating this response in men.
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PMID:Transient hypogonadotrophic hypogonadism after head trauma: effects on steroid precursors and correlation with sympathetic nervous system activity. 309 64

Labeled methyltrienelone was used to determine androgen receptor (AR) levels in cultured pubic skin fibroblasts in 40 infertile men with primary seminiferous tubule disorders and 18 normal men. LH pulse patterns and mean serum LH levels were also determined by blood sampling at 10-min intervals for 6 h. The infertile men and the normal men had similar mean receptor levels [mean, 28.1 +/- 2.0 (+/- SEM) and 24.8 +/- 1.8 fmol/mg protein, respectively]. However, 5 men with chromosomal disorders had a higher mean AR level (41.3 +/- 6.2 fmol/mg protein) than the normal men, and 5 of the remaining infertile men (14.2%) had receptor levels that were less than the minimum value in normal men. In men with idiopathic oligospermia, 19.0% had low receptor levels. Although mean serum FSH and testosterone levels were similar in the infertile men with low AR levels and in the normal men, mean LH levels were significantly elevated in this group (7.1 vs. 3.6 IU/L), the higher values being a result of increased LH pulse amplitude (mean, 5.6 vs. 2.8 IU/L). The LH-testosterone product (an index of androgen resistance) was also elevated in these men. When infertile men with low AR levels were matched with infertile men with normal receptor levels, the mean LH values were significantly elevated in the former, as was the LH-testosterone product. Testosterone values were similar in the two groups of men. After excluding subjects with chromosomal disorders, there were no significant correlations between AR levels and other indices of androgen action, such as semen volume, seminal fructose, or sex hormone-binding globulin levels. We conclude that AR levels are higher in patients with severe testicular failure associated with X-chromosome disorders. Also, AR defects were found in 19.0% of infertile men with idiopathic oligospermia. Finally, elevation of mean LH levels in men with seminiferous tubule disorders may reflect resistance to androgen action.
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PMID:Variable androgen receptor levels in infertile men. 310 95

The mechanism by which gonadal steroids modulate GH secretion is not known. We have used the reverse hemolytic plaque assay to examine whether gonadal steroid-induced modulation of GH secretion is effected by changes in the population of somatotrophs and/or alterations in their secretory properties. Two groups of Sprague-Dawley rats were studied: group 1 (n = 6) comprised male (M), castrate (Cx), and testosterone-replaced castrate male (Cx + T) rats and group 2 (n = 5) consisted of male (M), female (F), and 17 beta-estradiol-replaced castrate male (Cx + E) rats. The number of plaque-forming cells (expressed as both absolute number and a percentage of all cells) was determined, and secretory status was assessed by measuring plaque areas in response to 0, 0.01, 0.1, 1, 10, and 100 nM GHRH. While mean basal GH plaque areas were similar among the treatment groups of group 1, the maximal GH plaque area was significantly decreased in Cx [16.8 +/- 2.4 vs. 26.4 +/- 3.9 X 10(6) microns2 (mean +/- SEM); P less than 0.05], but not in Cx + T (27.5 +/- 4.1 microns2) rats. The GHRH EC50 was unaffected by castration or T replacement. The percentage and absolute population of somatotrophs were reduced in Cx, but not in Cx + T, rats, while the numbers of lactotrophs remained unchanged in these treatment groups. For group 2, the mean peak GH plaque area was reduced in Cx + E (16.5 +/- 2.9 microns2; P less than 0.001) compared to that in M rats (36.2 +/- 2.3 microns2), but was not significantly different from that in F (13.0 +/- 1.5 microns2) rats. The EC50 was significantly (P less than 0.025) greater in Cx + E (10.9 +/- 2.3 nM) and F (7.9 +/- 1.6 nM) compared to M rats (2.8 +/- 0.7 nM). The absolute somatotroph and lactotroph populations were increased in Cx + E compared to M and F rats, as were the populations of other pituitary cell types. Testosterone enhances GH secretion by increasing the secretory capacity, but not the sensitivity, of somatotrophs to GHRH and by recruiting the function of a subpopulation of somatotrophs. Estradiol reduces the secretory capacity and sensitivity of somatotrophs to GHRH, but increases the population of somatotrophs, lactotrophs, and non-GH- and non-PRL-secreting cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of gonadal steroids on somatotroph function in the rat: analysis by the reverse hemolytic plaque assay. 313 7


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