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The critical event in pubertal development, which is dependent on the maturation of gonadal function (gonadarche), is the establishment of the pulsatile secretion of GnRH, and hence of pituitary gonadotropins (Gn), which in turn activate sex steroid secretions estradiol (E2) in girls and testosterone (T) in boys. Adrenarche, characterized by increases in adrenal androgens, dehydroepiandrosterone...
Polycystic ovary syndrome (PCOS) can be considered the most common reproductive endocrine disease in which a tight link exists between hyperinsulinism and hyperandrogenism. According to this hypothesis, several authors reported that insulin stimulated androgen production in vitro by ovarian cells of hyperandrogenic women, influencing LH receptorial systems or several enzymatic steps of steroidogenic...
Neuroblastomas (NBs) are solid tumors of childhood that show undifferentiated cell phenotypes and poor prognosis. These tumors may occasionally differentiate and evolve toward a spontaneous regression. The development and the sexual differentiation of the central nervous system are influenced by sex steroids and by their metabolites derived from the actions of the enzymes aromatase, which converts...
We have investigated the changes in insulin-like growth factor 1 (IGF-1), IGF binding protein (IGFBP)-3, and sex steroids in normal male and female rats. Blood samples were obtained from 3-, 5-, 7-, 9-, 12-, 15-, and 20-week-old Wistar-Imamichi rats. In males, marked increases in serum IGF-1 and IGFBP-3 levels appeared earlier than that in serum testosterone level. IGF-1 and testosterone peaked...
It is well known that estrogens modulate bone cell activity and bone turnover after menopause. Our previous work has shown that developmental exposure of female mice to estrogen can increase peak bone mass in adulthood, suggesting a direct effect of estrogens on bone tissue turnover in different periods of life. Moreover, the developmental treatment of female mice with the synthetic estrogen agonist...
Synthesis of [3α- 3 H]7-dehydrocholesterol is described via protection of the 5,7-diene system in 7-dehydrocholesterol as the Diels-Alder adduct with 4-phenyl-1,2,4-triazoline-3,5-dione followed by oxidation of the hydroxyl group to give the 3-oxo adduct. Reduction of the keto adduct with [ 3 H]sodium borohydride produced the adduct of [3α- 3 H]7-dehydrocholesterol from which...
We have shown that the anabolic activity of estrogens on osteoblast and osteoblast-like cells can be synergistically enhanced by pretreatment with 1α, 25 (OH) 2 D 3 using the stimulation of the specific activity of the brain type isozyme of creatine kinase (CKB) as the response marker. The most likely cause of this synergy was the observed parallel increase in estrogen receptors....
We have examined the expression of both pituitary adenylate cyclase-activating polypeptide (PACAP) and PACAP receptor gene in the rat ovary using RT-PCR. mRNA was prepared from pregnant mare serum gonadotropin (PMSG)-treated, PMS-human chorionic gonadotropin (hCG)-treated, and hormone-untreated immature rat ovaries. mRNA from each group yielded a dominant DNA band corresponding in size to the PACAP...
The synthesis of Δ 7,9(11) -lanostadiene derivatives functionalized at C(32) starting from 3β-acetoxy-7α,32-epoxylanostan-11-one has been presented. The Δ 7,9(11) moiety was efficiently introduced in three steps in 71% yield by the regioselective abstraction of allylic 8β hydrogen. The formyl group of the key intermediate,...
Little is known about the fertility status of the women with Congenital Adrenal Hyperplasia (CAH). Here we report five pregnancies in three women with simple virilization form of CAH. Case 1, a 19-year-old married lady, presented with primary amenorrhoea and infertility. She had severe hirsutism, short stature, micromastia, and ambiguous genitalia (clitoromegaly, labial fusion, and single urogenital...
Sensitivity of the hypothalamic-pituitary system to glucocorticoid feedback declines with age in experimental animals. Alterations may arise from a reduced negative feedback control of the hypothalamic-pituitary-adrenal (HPA) axis, as suggested by the age-dependent loss of hippocampal adrenal steroid receptors in rats. To investigate the influence of aging on HPA function in man, glucocorticoid...
The 5α-reductase (5α-R) activates several 3keto-D4 steroids to more potent derivatives that may also acquire new biological actions. In males, testosterone (T) is the main substrate and gives rise to the most potent natural androgen, dihydrotestosterone (DHT). In females, progesterone is reduced to dihydroprogesterone, a precursor of tetrahydroprogesterone a natural anxiolytic/anesthetic steroid...
Colon cancer growth had been hypothesized to be influenced by sex steroids, but previous studies did not demonstrate any significant correlation with estrogen and progesterone receptors. It was also suggested that in cultured colon cancer cells, androgens could act as proliferative agents, but no definite conclusions about the involved molecular mechanism were reached. In the present study, HT-29...
The regulation of the hypothalamo-pituitary-adrenal (HPA) axis in the operative and perioperative period of major surgical procedures is necessary for successful adaption to surgical stress. We report evidence on an altered response of HPA axis regulation in patients who underwent coronary artery bypass grafting (CABG) surgery. Plasma levels of adrenocorticotropin (ACTH), β-endorphin, and cortisol...
Adipose tissue plays an important role in the metabolism of sex steroids, especially in women. To examine whether the tissue level of sex steroids varies in obesity and in different regions of the body, their concentration was assessed in adipose tissue from the abdominal integuments in 10 obese and 8 nonobese postmenopausal women and also in subcutaneous adipose tissue from the breast and abdominal...
The present study examined the effects of naloxone (N) and naltrexone-methobromide (NMB; an opioid receptor antagonist that does not cross the blood-brain barrier) on testicular steroidogenesis during acute immobilization stress (IMO; 2 h) in adult rats. Unstressed rats as well as IMO rats were treated by unilateral intratesticular injection of N (20 μg/testis), NMB (36 μg/testis), or vehicle at...
An increasing number of radio- and enzyme-immunoassay kits for the determination of bone specific markers are commercially available. Most of these markers are type I collagen fragments and were found to reflect severe disorders in bone metabolism, e.g., morbus Paget. From those findings, it was concluded that they should represent a tool to monitor bone loss and the effect of hormonal replacement...
Glucocorticoid excess bears the risk of inducing secondary osteoporosis. In endogenous Cushing's syndrome, osteoporosis may be the symptom of the underlying disease. Bone loss may be reversed after curing the condition, but often treatment of established osteoporosis is necessary. In case of long-term glucocorticoid treatment using relevant doses, bone loss is to be expected and should be prevented...
Nuclear bodies (NB) are dynamic substructures in the interchromatin of interphase nuclei, regarded as markers of stimulated rRNA synthesis. We have shown earlier that during the rat estrous cycle, the frequency of complex nuclear bodies in endometrial cavum and glandular epithelial cells is temporally correlated with the expression of estrogen (ER) and progesterone (PR) receptors and is estrogen...
Previous studies indicate that acute immobilization stress (IMO, 2 h) impaired testicular steroidogenesis primarily at the testicular level. IMO reduced serum testosterone (T) levels without altering serum luteinizing hormone (LH) values (Maric et al., J Steroid Biochem Mol Biol 1996:58;351-355). In this study, we investigated the effect of IMO (2 h) and intratesticular injection of naltrexone-methobromide...
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