Basal Plasma Testosterone Levels Research Articles

Gastric Leiomyoma Misdiagnosed as a Left Cystic Adrenal Tumor

Gastrointestinal leiomyomas often occur in the esophagus, colon, and rectum, but are very rare in the stomach. The patient was referred to Jeju national university medical center for the treatment of a left adrenal tumor diagnosed 5 years ago. She had a long history of repeated left flank pain, nausea, and abdominal distension for the last few years. Annual follow-up computed tomography scan showed a no changed 5×5.5-cm sized multiloculated left adrenal cystic lesion. Laboratory tests revealed that the basal levels of plasma adrenocorticotropin, cortisol, aldosterone, renin, testosterone, adrenaline, noradrenaline, and dopamine were normal findings. The preoperative diagnosis was a left nonfunctioning adrenal neoplasm with symptom of discomfort. However, the tumor revealed as an exophytic growing leiomyoma with cystic changes of a stomach by surgery. The mass was found at the posterior wall of the fundus and about 5-cm-sized mass. Resection of the tumor was performed using laparoscopy. The pathologic diagnosis revealed a gastrointestinal leiomyoma with a benign cystic lesion lined by respiratory epithelium with an old hemorrhage and chronic gastritis. The patient had no evidence of recurrence during the 12-month follow-up. Gastric leiomyoma is unfamiliar to the usual urologists. It needs to take gastric leiomyoma into account if the left adrenal tumor is close to the stomach. Herein, we report the case of a 44-year-old woman with gastrointestinal leiomyoma misdiagnosing as a nonfunctioning adrenal tumor.

Correlation Between Personality Traits and Testosterone Concentrations in Healthy Population.

Objective:High plasma testosterone levels have been associated with aggression, sexual behaviour and social status. The aim of this paper was to study the correlation between basal plasma testosterone levels and personality variables in healthy participants.Materials and Methods:Fifty-four participants were randomly enrolled into this study. Basal plasma testosterone levels were measured between 8:30 am and 10 am. After 24 hours of blood drawing, each subject completed personality questionnaires.Results:Positive correlation between basal plasma testosterone levels and anti-social personality traits in both genders was observed (r = 0.336 and P < 0.018). Also, a positive correlation was observed between basal plasmatestosterone levels and criminal thinking traits (r = 0. 376, P < 0.05) and Millon compulsive (r = 0.386, P < 0.010) in both genders. In female participants, a positive correlation between basal plasmatestosterone levels and psychoticism (r = 0. 25, P < 0.019) and Cloninger AUTO TCI (r = 0.507, P < 0.004) was observed. In males participants positive correlation between baseline plasmatic Testosterone levels and Millon Antisocial trait (r = 0. 544, P < 0.19) and Millon Hypomania trait (r = 0. 485, P < 0.41) and Millon Drug Abuse trait (r = 0.632, P < 0.05) was reported.Conclusion:Our results suggest gender differences in clinical and personality variables related with basal plasma testosterone level. In men, high plasma testosterone levels were associated with clinical traits, substance abuse and hypomania. Women with higher basal testosterone levels showed higher scores on personality self-direction traits.

Relationship between adult dark spermatogonia and secretory capacity of Leydig cells in cryptorchidism

To examine whether hormonal therapy before orchidopexy affects the histology of the testis and to assess the responsiveness of the Leydig cells, as it has been shown that although basal plasma testosterone levels are within the 'normal' range in cryptorchid boys there is an insufficient increase of testosterone after a human chorionic gonadotrophin (hCG) stimulation in approximately 30% of cryptorchid boys. In all, 55 boys (aged 1-7 years) with a unilateral undescended testis were included in the study and divided into two groups. Group I (32 boys) received hormonal therapy before orchidopexy; 17 boys received a long-acting LHRH analogue (buserelin) administered as a nasal spray in doses of 20 microg/day for 28 days, followed by 1500 IU hCG intramuscularly (i.m.) once a week for 3 weeks, and the remaining 15 received 1500 IU hCG i.m. once a week for 3 weeks. Group II (33 boys) had orchidopexy alone. During orchidopexy biopsies were taken from the undescended and contralateral descended testes of the boys in both groups for histological analyses. Variations in the number of adult dark (Ad) spermatogonia per tubule (Ad/T) were assessed and testosterone levels were measured during the course of the hormonal therapy (before treatment, 14 days after initiation of buserelin administration, 24 h after each hCG injection, and 3 months after cessation of therapy). In group I, 17 boys (53%) had a 'normal' Ad/T after hormonal treatment vs only six (18%) in group II after orchidopexy alone (P = 0.019). In the hormonally treated boys (group I) we compared the testosterone values 24 h after the second injection of hCG (when the response was most pronounced). Those with a normal Ad/T had a mean (sd) testosterone level of 199.5 (97.6) ng/dL vs 99.6 (85) ng/dL in those with an inadequate Ad/T response to hormonal therapy (P < 0.003). We have confirmed that there are two subgroups of cryptorchid boys. Patients with a sufficient Leydig cell secretory capacity will have normal testicular histology and Ad spermatogonia count after hormonal treatment. While those with a suboptimal Leydig cell capacity will have a low Ad spermatogonia count and consequently poor prognosis for future fertility, despite successful surgery. As to whether different types and durations of the hormonal therapy in patients with impaired Leydig cell response could lead to improved testicular histology and consequently improved prognosis for future fertility, remains to be answered.

Ovarian sex cord-stromal tumor, unclassified: case report of endocrinologic findings and review of the literature

Endocrinologic findings and a successful pregnancy in a 39-year-old woman with significant androgen excess due to a biologically active, virilizing ovarian sex cord-stromal tumor, unclassified, are described. She had secondary amenorrhea, infertility, and hirsutism. Her basal plasma testosterone level was high at 187 ng/mL (normal range: 10-85 ng/mL). Tumor resection resulted in resumption of ovulation, pregnancy, and delivery.

Male reproductive function is not affected in prolactin receptor-deficient mice.

Mice with a targeted disruption of the prolactin (PRL) receptor gene were used to study the physiological role of PRL in the control of the male reproductive function. Fertility parameters as well as body and reproductive organ weights (epididymis and testes) were unaffected in PRL receptor knockout mice. Testicular histology and sperm reserves were also normal. Compared with wild-type animals, knockout mice had no significant difference in basal plasma LH, FSH, and testosterone levels, and the weight of seminal vesicles and prostate was unaffected. Moreover, no alteration was detected in human chorionic gonadotropin-induced testosterone levels. It is concluded that the absence of PRL signaling is not detrimental to male testicular function and to fertility in the mouse.

Management and outcome of central precocious puberty

Management and outcome of central precocious puberty

Plasma Steroid-Binding Globulin Mediation of Differences in Stress Reactivity in Alternative Male Phenotypes in Tree Lizards, Urosaurus ornatus

Plasma steroid-binding globulins, for example, corticosteroid-binding globulin and sex hormone-binding globulin (SHBG), have been identified in a number of vertebrates. One possible function of these proteins is to regulate the amount of steroid delivery to target tissues, as only free steroids are believed to diffuse from the circulation to target cells. Male tree lizards, Urosaurus ornatus, exhibit alternative male reproductive tactics correlated with dewlap (throat-fan) coloration. Males with orange-blue dewlaps are aggressive and territorial, whereas males with orange dewlaps are less aggressive and employ a satellite strategy. The two types of males have similar basal levels of total plasma corticosterone and testosterone. However, testosterone levels of nonterritorial males are more sensitive than those of territorial males to negative regulation by stress-induced increases in corticosterone. We tested the hypothesis that this difference in corticosterone feedback on testosterone could be mediated, in part, by differences in binding globulin levels between the two types of males. We have identified two steroid-binding globulins in male tree lizards. The first binds androgens and estradiol with high affinity (10−9 M) and is similar to previously described sex hormone-binding globulins. The second binds both androgens and C21 steroids, such as progesterone and corticosterone, with higher specificity than estradiol and is best described as an androgen-glucocorticoid-binding globulin (AGBG). In both types of males, the capacity of AGBG is much higher than SHBG. In addition, AGBG capacity is significantly greater in territorial than nonterritorial males, whereas the capacity of SHBG does not differ between the two types of males. Calculations of free steroid levels based on the affinity and capacity measures suggest that although most testosterone circulates bound to binding globulins, binding capacity is high enough that binding globulins are also able to bind to other steroids such as corticosterone. Thus, differences in binding capacity between the two types of males could result in higher levels of free corticosterone in nonterritorial males than in territorial males, especially during stress-induced increases in corticosterone, and may explain why testosterone levels of nonterritorial males are more sensitive to negative feedback by corticosterone.

Regulation of thyroid hormones on the production of testosterone in rats

The effects of a thyroidectomy and thyroxine (T4) replacement on the spontaneous and human chorionic gonadotropin (hCG)-stimulated secretion of testosterone and the production of adenosine 3',5'-cyclic monophosphate (cAMP) in rat testes were studied. Thyroidectomy decreased the basal levels of plasma luteinizing hormone (LH) and testosterone, which delayed the maximal response of testosterone to gonadotropin-releasing hormone (GnRH) and hCG in male rats. T4 replacement in thyroparathyroidectomized (Tx) rats restored the concentrations of plasma LH and testosterone to euthyroid levels. Thyroidectomy decreased the basal release of hypothalamic GnRH, pituitary LH, and testicular testosterone as well as the LH response to GnRH and testosterone response to hCG in vitro. T4 replacement in Tx rats restored the in vitro release of GnRH, GnRH-stimulated LH release as well as hCG-stimulated testosterone release. Administration of T4 in vitro restored the release of testosterone by rat testicular interstitial cells (TICs). The increase of testosterone release in response to forskolin and androstenedione was less in TICs from Tx rats than in that from sham Tx rats. Administration of nifedipine in vitro resulted in a decrease of testosterone release by TICs from sham Tx but not from Tx rats. The basal level of cAMP in TICs was decreased by thyroidectomy. The increased accumulation of cAMP in TICs following administration of forskolin was eliminated in Tx rats. T4 replacement in Tx restored the testosterone response to forskolin. But the testosterone response to androstenedione and the cAMP response to forskolin in TICs was not restored by T4 in Tx rats. These results suggest that the inhibitory effect of a thyroidectomy on the production of testosterone in rat TICs is in part due to: 1) the decreased basal secretion of pituitary LH and its response to GnRH; 2) the decreased response of TICs to gonadotropin; and 3) the diminished production of cAMP, influx of calcium, and activity of 17beta-HSD. T4 may enhance testosterone production by acting directly at the testicular interstitial cells of Tx rats.

Neuroendocrine-Related Effects of Long-Term, ‘Binge’ Cocaine Administration: Diminished Individual Differences in Stress-Induced Corticosterone Response

Acute cocaine administration activates behavioral and neuroendocrine processes associated with the stress response. However, much less is known about the effects of chronic, long-term cocaine administration on neuroendocrine adaptations and individual vulnerability to stress. We hypothesized that chronic ‘binge’ cocaine administration may serve as a chronic pharmacological stressor leading to a hyperactivity of the stress-responsive hypothalamic-pituitary-adrenal (HPA) axis and alterations in its feedback mechanisms. In order to test this hypothesis, the effects of long-term (3 and 6 weeks) ‘binge’ pattern cocaine administration (3×15 mg/kg cocaine, i.p., daily, during the early phase of the light cycle) on body weight, adrenal gland weight, basal and stress-induced activity of the corticosterone (CORT) and basal plasma testosterone (T) levels were measured. Both 3 and 6 weeks ‘binge’ cocaine administration decreased body weight gain, increased the weight of adrenal glands and increased basal CORT levels. Plasma T levels were suppressed by both 3 and 6 weeks of cocaine treatment. No correlation was found between elevated CORT and low T levels at any time point. Neither chronic saline nor cocaine administration altered stress-induced CORT secretion. CORT levels 60 min following the restraint stress (recovery) were significantly lower than pre-stress basal levels after 3 and 6 weeks of cocaine, but not saline, administration. Moreover, initial individual differences in stress-induced CORT response, i.e. low and high responsivity to restraint prior to any saline or cocaine injections, were maintained in control rats but became diminished in cocaine-treated rats. These results indicate that chronic binge cocaine administration leads to sustained activation of the HPA axis and alters processes underlying individual vulnerability to stress.

Neuroendocrine effect of a short-term treatment with DHEA in postmenopausal women

Objectives: A progressive decline of plasma dehydroepiandrosterone (DHEA) levels occurs in women during aging related to the reduction of adrenocortical secretion. A specific action of DHEA on the central nervous system (CNS) is suggested by the improvement of psychological and physical well-being in postmenopausal women after DHEA supplementation. The aim of the present study was to investigate the neuroendocrine effects of short-term DHEA supplementation in postmenopausal women, evaluating changes of plasma β-endorphin ( β-EP) and growth hormone (GH) before and after oral DHEA (100 mg/day) for 7 days in postmenopausal women ( n=6). Methods: Before and after 7 days of DHEA supplementation, postmenopausal women underwent a neuroendocrine test with clonidine, an α2 presinaptic agonist for adrenergic system, (1.25 mg i.v.). Basal plasma DHEA, androstenedione (A), testosterone (T), estrone (E 1) and estradiol (E 2) levels were evaluated before and after treatment, while plasma β-EP and GH levels were measured before and 15, 30, 45, 60 and 90 min after clonidine injection. Results: Basal plasma β-EP and GH levels did not show a significant difference before and after short-term DHEA administration, while circulating A, T, E 1 and E 2 significantly increased after treatment. The clonidine test induced a significant increase of plasma β-EP levels in women after receiving DHEA supplementation but not before; conversely, plasma GH levels increased both before and after treatment. Conclusions: The present study indicates that short-term DHEA supplementation in postmenopausal women is able to restore the impaired response of pituitary β-EP to clonidine, an α2 presinaptic agonist. According to these data it is possible to hypothesize that DHEA could play a role in the psychological and physical well-being of postmenopausal women acting via a restoration of neuroendocrine control of antero-pituitary β-EP secretion.

Differential Lateral Septal Vasopressin in Wild-type Rats: Correlation with Aggression

The vasopressin (VP)-containing projections from the cells of the bed nucleus of the stria terminalis to the lateral septum (LS) are sexually dimorphic and dependent on gonadal steroids. Recently, the difference in VP distribution found among both sexes was also demonstrated in male mice genetically selected for different levels of intermale aggression. In the present study we examined whether this differential VP distribution in males also exists in an outbred strain of wild-type rats. After the animals were tested for their level of aggression, the VP content and the fiber density of the LS were measured using radioimmunoassay and immunocytochemistry, respectively. In addition, basal levels of plasma testosterone (T) were measured. Both biochemical data and immunocytochemical data revealed a negative correlation between VP and intermale aggression. Aggressive rats exhibited low levels of VP whereas intermediate and nonaggressive animals showed higher levels. Differences in adult levels of T were not found. The results are in accordance with the observations previously found in male mice, reconfirming the correlation between lateral septal VP and aggression.

Effect of aging on erythropoietin secretion in male rats.

The secretion of erythropoietin (EPO) and testosterone in response to hypoxia in old (22-25 months), middle (mid)-aged (15-17 months), adult (6-7 months), and young (3 months) male rats was studied. Rats of different ages were bled by cardiac puncture before and subsequent to 8 h exposure to 12% O2. The metabolic clearance rate of EPO was determined by a single-injection method. The effects of orchidectomy and replacement of testosterone propionate on plasma EPO concentrations were also investigated. Analysis of the direct effects of testosterone on EPO release from kidney tissue was carried out in an in vitro study. Both basal and hypoxia-induced EPO levels were lower in old rats than in mid-aged, adult, and young rats (p < .01). Plasma testosterone levels decreased in response to hypoxia in all rats (p < .01 for young, adult, and mid-aged rats, and p < .05 for old rats). The old rats also had lower plasma testosterone levels following hypoxia when compared with other rats (p < .05). The metabolic clearance rate of EPO was not affected by age. Orchidectomy decreased rat plasma EPO concentration (p < .05). This decrease could be restored to intact levels after testosterone propionate replacement. Both 10(-10) M (p < .05) and 10(-9) M (p < .01) testosterone stimulate EPO release from kidney tissue in vitro. Our findings indicate that the basal levels of plasma EPO and testosterone are decreased, and the hypoxia-induced EPO is also diminished with aging in male rats. These data suggest that the mechanism of tolerance to hypoxia and the endocrine function of the kidneys in male rats during the aging process are testosterone-dependent.

Premature decline of the testicular endocrine function in rats with hereditary galactosemia

Testicular endocrine function and morphometric characteristics of the genital system are examined in W/SSM (galactose sensitive) and R (galactose resistant) rats aging 3 and 10 months. Testicular hypertrophy (in comparison with R rats) is found in W/SSM rats of both ages. Basal plasma testosterone levels in young and old rats of both strains did not differ. Afterin vivo stimulation of the testes with chorionic gonadotropin, the increment of plasma testosterone in 10-month-old W/SSM rats was 2-fold lower than in young rats and in age-matching R rats. Premature decrease of testicular endocrine function in W/SSM may reflect a more intense aging of these animals.

Hormonal Alterations and Reproductive Inhibition in Male Fence Lizards (Sceloporus occidentalis) Infected with the Malarial Parasite Plasmodium mexicanum

When naturally infected with the malarial parasite Plasmodium mexicanum, Western fence lizards, Sceloporus occidentalis, exhibit numerous reproductive pathologies. Infected males display fewer courtship and territorial behaviors, have altered sexually dimorphic coloration, and have smaller testes. Infected animals store less fat by late summer, which, for females, reduces clutch size in the spring We describe hormonal alterations associated with malarial parasitism that may underlie this reproductive inhibition. We caught lizards in the field and bled them either immediately or 1 h after capture for measurement of basal and stress levels of steroid hormones. Compared to uninfected lizards, infected lizards had lower levels of basal plasma testosterone (24 vs. 38 ng/mL) and higher levels of corticosterone (18 vs. 8 ng/mL) following 1 h of capture and confinement. Infected animals also had lower levels of plasma glucose (243 vs. 270 mg/dL). When we experimentally elevated plasma corticosterone of uninfected...

True hermaphroditism: Genetic variants and clinical management

The diagnosis and management of 22 patients with true hermaphroditism are described. Sixteen of them were first seen before the age of 4 months. The initial manifestations were ambiguous genitalia in 20 cases (two of them identified prenatally by ultrasound examination), isolated clitoromegaly in one, and penile hypospadias plus unilateral cryptorchidism in one. All patients but one had at least one palpable gonad. Eleven of the twelve patients examined before the age of 6 months had basal plasma testosterone levels >0.4 ng/ml. In older patients the stimulation test was necessary to demonstrate male testosterone secretion. The most common peripheral karyotype was 46,XX (17 cases); the other karyotypes were 47,XXY (1 case) and mosaicism 46,XX/46,XY (2 cases) or 46,XX/47,XXY (2 cases). One of the patients with the 46,XX karyotype had 46,XX/46,XY on fibroblast culture; four had the SRY gene in their leukocytes and one in the tissue taken at gonadal biopsy. A vagina was found in all patients at laparotomy, and a uterus was found in 17 cases (as a hemiuterus in 9). Genitography failed to demonstrate a uterus in only one case. The testicular tissue was dysgenetic but the ovarian tissue was normal. Sex assignment was male in 8 patients (reoriented by us in 2) and female in 14 patients (reoriented by us in 3). Spontaneous pubertal development occurred in the 4 patients (2 boys, 2 girls) with gonadal tissue who reached pubertal age. We conclude that true hermaphroditism is a heterogeneous condition in terms of its genetic background, with a prevalence of the 46,XX karyotype. There may be mosaicism with a Y-bearing cell line limited to the gonad (its frequency is probably underestimated), a paternal meiotic exchange between X and Y occurring in 46,XX cases with SRY, or a lack of the SRY gene, suggesting that other genes working independently of SRY may also determine testicular differentiation. (J PEDIATR 1994;125:738-44)

Calcitonin inhibits testosterone and luteinizing hormone secretion through a mechanism involving an increase in camp production in rats

Effects of calcitonin peptides, including human calcitonin (hCT), salmon calcitonin (sCT), and calcitonin gene-related peptide (CGRP), on the secretion of testosterone and luteinizing hormone (LH) in male rats were studied. Male rats were injected intravenously with human chorionic gonadotropin (hCG), calcitonin peptides, or hCG plus calcitonin peptides. Blood samples were collected at several intervals following hormone challenge. In an in vitro experiment, testis blocks were incubated with hCG (0, 0.05, 0.5, or 5 IU/ml) or hCG (0.5 IU/ml) plus calcitonin peptides (0-10(-9) or 10(-6) M) at 34 degrees C for 30 minutes. Both medium and plasma samples were extracted by ether and analyzed for testosterone by radioimmunoassay (RIA). The concentration of calcium in each plasma sample was measured by an automatic calcium analyzer. The anterior pituitary gland (AP) was incubated with or without calcitonin peptides (0-10 nM) at 37 degrees C for 30 minutes. They were then incubated with gonadotropin releasing hormone (GnRH, 10 nM) for a further 30 minutes. The concentration of LH in AP medium was measured by RIA. The accumulation of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) in both testicular tissues and APs were measured by RIA. A single intravenous injection of calcitonin peptides decreased the basal and hCG-stimulated levels of plasma testosterone gradually from 60 to 180 or 360 minutes after challenge. The plasma calcium was not altered by the injection of calcitonin peptides and/or hCG. Administration of calcitonin peptides in vitro resulted in a dose-dependent inhibition of both basal and hCG-stimulated release of testosterone.(ABSTRACT TRUNCATED AT 250 WORDS)

Predictive value of luteinizing hormone releasing hormone (LHRH) bolus testing before and after 36-hour pulsatile LHRH administration in the differential diagnosis of constitutional delay of puberty and male hypogonadotropic hypogonadism.

Intravenous LHRH bolus testing (100 micrograms) after 36 h of pulsatile LHRH administration (5 micrograms/90 min) preliminary has been reported to allow complete differentiation between constitutional delay of puberty (DP) and hypogonadotropic hypogonadism (HH) in a small group of sexually immature patients. So far, these data have never been confirmed. To assess the discriminatory power of the test, 33 patients with a presumptive diagnosis of either DP (n = 17) or HH (n = 16), confirmed by clinical follow-up, were studied accordingly. Both groups of patients had similar mean basal LH and FSH levels (P > 0.10). The mean basal plasma testosterone level was three times higher in DP than in HH (4.2 +/- 1.0 vs. 1.4 +/- 0.2 nmol/L, P* < 0.001), but there was a wide overlap. In response to the first LHRH bolus test, the mean LH increment was significantly lower in HH than in DP patients (P < 0.001), but, in 44% of the patients, the values overlapped. The FSH increments were similar in HH and DP. Pulsatile LHRH administration for 36 h similarly increased LH levels in HH and DP to values (2.7 +/- 0.4 and 3.8 +/- 0.5, respectively) slightly higher than before (P < 0.01), but again, not statistically significantly different from each other. The mean testosterone levels increased 2-fold in both groups and remained significantly higher in DP than in HH (7.6 +/- 2.1 vs. 2.8 +/- 0.5 nmol/L P* < 0.05). The mean FSH levels after priming also rose, however, to levels significantly higher in HH than in DP (5.2 +/- 0.8 vs. 3.5 +/- 0.4, P* < 0.05). In HH the ratio of FSH to LH almost doubled, whereas it virtually remained unchanged in DP. LHRH bolus testing after LHRH priming evoked a significantly lower LH response in both HH and DP than before priming despite only slightly higher baseline LH values. The LH increment in HH was five times lower in HH than in DP. In any of the 16 HH patients, the LH increment was < or = 3 IU/L, whereas in 15 out of 17 DP patients the increase was higher (sensitivity of the test 100%, specificity 88%, and diagnostic efficiency 94% after LHRH priming against 56%, 94%, and 75% respectively, before LHRH priming.(ABSTRACT TRUNCATED AT 400 WORDS)

Effects of adrenocorticotropin on adrenal and plasma 11β-hydroxyandrostenedione in the guinea pig and determination of its relative androgen potency

In order to gain a better understanding of adrenal steroid production in guinea pigs, adrenocorticotropin (ACTH) was administered to castrated adult guinea pigs and a series of C-21 and C-19 steroid levels were determined in both adrenals and plasma over a 6-h period. After injection of ACTH, adrenal cortisol and corticosterone concentrations were stimulated by almost 40- and threefold, respectively, whereas the content of C-21 steroid precursors, namely pregnenolone, 17-hydroxypregnenolone, progesterone, and 17-hydroxyprogesterone, was stimulated by two- to 10-fold. Increases of C-19 steroid levels, namely dehydroepiandrosterone (DHEA), androstenedione (4-DIONE), testosterone, and llβ-hydroxyandrostenedione (11β-DIONE) ranging from 1.5 to eight times were also observed in the adrenals. In castrated guinea pigs, basal plasma DHEA, 4-DIONE, and testosterone levels were undetectable by radioimmunoassay, whereas 11β-DIONE concentrations were in a range similar to those in intact animals. In plasma, ACTH had a marked effect on corticosterone, cortisol, and 11β-DIONE. The present results indicate that although guinea pig adrenals synthesized several C-19 steroids, only 11β-DIONE was secreted by the adrenals into circulation even after administration of ACTH. The biological activity of this hydroxylated C-19 steroid was then assessed by using silastic implants in castrated guinea pigs, and it was shown that plasma 11β-DIONE concentrations increased by threefold and had no effect on prostate weight. Moreover, by using ZR-75-1 cells, a mammary cancer cell line extremely sensitive to androgens, we demonstrated that 11β-DIONE had an androgenic potency 35-fold less than that ofdihydrotestosterone. (Steroids 58:29–34, 1993)

Growth Hormone and Insulin-Like Growth Factor I Treatment Increase Testicular Luteinizing Hormone Receptors and Steroidogenic Responsiveness of Growth Hormone Deficient Dwarf Mice*

To test the hypothesis that insulin-like growth factor (IGF-I) is required for the in vivo development of testicular Leydig cell function, either recombinant human GH [(hGH) (1.5 micrograms/g BW) or recombinant IGF-I (1 microgram/g BW) was injected three times daily into immature Snell dwarf mice (dw/dw) and into phenotypically normal control (Dw/-) for 7 days. In dw/dw mice hGH enhanced significantly body, liver, kidney, and testicular weight. In addition, hGH increased testicular LH receptors and the acute steroidogenic response to human CG, but there was no significant effect on basal plasma testosterone or plasma LH levels. The effects of IGF-I in body and kidney weight were less pronounced than those produced by hGH, but its effects on testicular weight and LH receptors, as well as on the acute steroidogenic response to human CG, were similar to that observed after hGH treatment. In Dw/- mice hGH had no effect on either body or organ weight or on testicular function, despite the fact that it induced a significant increase in plasma IGF-I levels. These results indicated that IGF-I is able to induce the maturation of Leydig cell function and that the effects of hGH on the testis are probably mediated by IGF-I. They also suggest that the delayed puberty associated with GH deficiency or resistance is most likely related to an IGF-I deficiency.

Testicular function following cyclophosphamide treatment for childhood nephrotic syndrome: long-term follow-up study

Testicular function of 17 males treated in childhood or adolescence for nephrotic syndrome (NS) with cyclophosphamide (CY) for a mean time of 240 days (mean total dosage of 16.4 g or 641 mg/kg body weight) was evaluated at a mean time of 11.8 years after treatment. Five were azoospermic, 1 oligospermic, and 11 normospermic. There was a significant inverse correlation of sperm density with CY dosage and duration of treatment. All patients had undergone normal pubertal development and had normal sexual characteristics. Both basal and gonadotropin-releasing hormone-stimulated follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations were significantly raised in oligo- and azoospermic patients. Raised basal and peak FSH and LH concentrations in normospermic patients with a sperm count of less than 40 x 10(6)/ml were in keeping with impairment of two testicular components. However, mean basal plasma testosterone levels and mean peak plasma testosterone responses to human chorionic gonadotropin (HCG) did not differ significantly between patients and controls. Although LH responses to gonadotropin-releasing hormone suggested compensated Leydig cell failure in patients with testicular tubular damage, secretory reserve capacity of these cells, estimated by a HCG stimulation test, was preserved. Further follow-up is required to ascertain whether in these patients Leydig cell failure will develop with time.