bluuebunny/crossref_metadata_2025 huggingface dataset:
Insulin treatment fails to abolish the teratogenic potential of serum from diabetic rats
Authors: Wentzel Parri , Eriksson Ulf J
Published: December 2008

Wentzel P, Eriksson UJ. Insulin treatment fails to abolish the teratogenic potential of serum from diabetic rats. Eur J Endocrinol 1996;134:459–66. ISSN 0804–4643

Maternal diabetes during pregnancy constitutes an increased risk for congenital malformations in the offspring. Previous studies have identified several serum components with teratogenic activity, e.g. glucose and β-hydroxybutyrate, but have also suggested that the teratogenic influence of the diabetic environment on the developing embryo is multifactorial and may depend upon changed concentrations of several maternal metabolites. In the present investigation we aimed to assess the teratological impact of small, concomitant alterations in a series of metabolites, particularly those not previously identified as teratogens. We thus investigated the influence of a mild diabetic environment by culturing gestational day-9 rat embryos in serum from insulin-treated diabetic rats for 48 h in vitro, and compared the embryonic outcome with that obtained after culture in normal serum and in serum from manifestly diabetic rats without insulin treatment. The glucose concentration was adjusted to 10 or 30 mmol/l in the cultures, and the embryos were evaluated with respect to crown–rump length, protein and DNA content, number of somites and malformation score (comparing major, minor or no malformations). We found that increased glucose levels caused embryonic maldevelopment in both normal and diabetic serum, and that despite normalization of the diabetic state, the serum from the insulin-treated diabetic rats caused more growth retardation than the nondiabetic control serum. The normalized diabetic serum was also more teratogenic than the normal serum at the low glucose concentration, whereas the serum from the manifestly diabetic rats tended to cause more dysmorphogenesis at 30 mmol/l glucose than both the normal and normalized diabetic serum. The results suggest that the teratogenicity of maternal serum in diabetic pregnancy is not mediated exclusively by increased concentrations of glucose and ketone bodies. The efforts to diminish the teratogenic effects of a diabetic environment should therefore include normalization of a multitude of serum factors, including glucose and ketone bodies.

Parri Wentzel, Department of Medical Cell Biology, University of Uppsala, Biomedicum, PO Box 571, S-751 23 Uppsala, Sweden
No correlation of growth hormone receptor gene mutation P561T with body height
Authors: Chujo Seiko , Kaji Hidesuke , Takahashi Yutaka , Okimura Yasuhiko , Abe Hiromi , Chihara Kazuo
Published: December 2008

Chujo S. Kaji H, Takahashi Y. Okimura Y, Abe H, Chihara K. No correlation of growth hormone receptor gene mutation P561T with body height. Eur J Endocrinol 1996;134:560–2. ISSN 0804–4643

Analysis of the growth hormone receptor (GHR) gene in GH insensitivity syndrome revealed various mutations, mainly in the gene encoding the extracellular domain of GHR. On the other hand, the mutation of the gene encoding the cytoplasmic domain of GHR was not found. We have reported, in the cytoplasmic domain of a GHR gene, mutation P561T in a patient with Noonan syndrome who showed a blunted insulin-like growth factor I (IGF-I) response to an acute injection of GH. However, her mother possessing the same mutation had no growth failure. To clarify the significance of the GHR gene mutation P561T, 96 volunteers (41 males aged 21–80 years; 55 females, aged 20–80 years) were tested for the presence of this mutation. By the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, three of the 41 males and 11 of the 55 females examined revealed heterozygous missense mutation P561T, The body height (cm) was 168 ±5.3 (mean ± sd) in three males with the mutation and 164.1 ± 5.8 in 38 males without the mutation. The difference between them was not statistically significant. The body height in 11 females with the mutation was 152.6 ± 5.4, which did not differ significantly from 151.3 ± 6.2 in 44 females without the mutation. These findings suggest that the heterozygous missense mutation P561T in the cytoplasmic domain of GHR does not play a significant role in determining the final body height.

Hidesuke Kaji, Third Division, Department of Medicine, Kobe University School of Medicine. 7-5-1. Kusunokicho, Chuo-ku, Kobe 650, Japan
Adrenocorticotropin-independent bilateral macronodular adrenocortical hyperplasia: immunohistochemical studies of steroidogenic enzymes and post-operative course in two men
Authors: Wada Norio , Kubo Mitsumasa , Kijima Hiromichi , Ishizuka Tatsuya , Saeki Tomoko , Koike Takao , Sasano Hironobu
Published: December 2008

Wada N, Kubo M, Kijima H, Ishizuka T, Saeki T, Koike T, Sasano H. Adrenocorticotropin-independent bilateral macronodular adrenocortical hyperplasia: immunohistochemical studies of steroidogenic enzymes and post-operative course in two men. Eur J Endocrinol 1996;134:583–7. ISSN 0804–4643

We treated two men with Cushing's syndrome due to adrenocorticotropin (ACTH)-independent bilateral macronodular adrenocortical hyperplasia (AIMAH). In both patients, plasma ACTH was low and plasma cortisol was not suppressed by a high dose of dexamethasone (8 mg) but was remarkably responsive to exogenous ACTH. The adrenal glands were extremely enlarged and contained multiple nodules composed of large clear cells and small compact cells. The immunore-activity of P-45017α was predominant in the small compact cells, while that of 3β-hydroxysteroid dehydrogenase (3 β-HSD) was observed exclusively in the large clear cells. Among various adrenocortical disorders, differential expression of 3β-HSD and P-45017α in clear and compact cells has heretofore been demonstrated only in AIMAH. Total adrenalectomy was done for one patient, and partial adrenalectomy for the other. In the former patient, the normal diurnal rhythm of plasma ACTH was restored 11 months postoperatively. In the latter patient, the normal dynamics in the hypothalamic-pituitary-adrenal axis became evident 15 months after surgery. Thus AIMAH is apparently a primary adrenocortical disorder and is not due to abnormalities of the hypothalamus or pituitary.

Mitsumasa Kubo, Department of Medicine II, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kita-Ku, Sapporo 060, Japan
Domestic cats show episodic variation in plasma concentrations of adrenocorticotropin, α-melanocyte-stimulating hormone (α-MSH), cortisol and thyroxine with circadian variation in plasma α-MSH concentrations
Authors: Kemppainen Robert J , Peterson Mark E
Published: December 2008

Kemppainen RJ. Peterson ME. Domestic cats show episodic variation in plasma concentrations of adrenocorticotropin, α-melanocyte-stimulating hormone (α-MSH), cortisol and thyroxine with circadian variation in plasma α-MSH concentrations. Eur J Endocrinol 1996:134:602–9. ISSN 0804–4643

Blood samples were collected from 31 healthy domestic cats to characterize possible episodic and/or circadian variation in plasma concentrations of adrenocorticotropin (ACTH), cortisol, thyroxine and α-melanocyte-stimulating hormone (α-MSH). Samples were collected with minimal disturbance through indwelling jugular cannulae at two frequencies: at 20-min intervals for 3 h for evaluation of episodic variation, and at 2-h intervals for 48 or 72 h to identify possible circadian changes. Episodic peaks in profiles of all hormones were found in the majority of cats. When data were compared across four bleed periods (each of 3 h duration), no differences were detected in average hormone concentrations or characteristics of episodic pulses. Correlation analyses showed a significant (p < 0.001) relationship between concentrations of ACTH and cortisol (r = 0.44) when these hormones were measured in the same plasma sample. A weaker but significant correlation (r = 0.13,p < 0.05) was also detected between concentrations of ACTH and α-MSH, suggesting that proopiomelanocortin peptide secretion from the pars distalis and pars intermedia occurs at least on occasion in synchrony. No differences in hormonal profiles were noted when comparing data across sexes. Data from the studies designed to evaluate circadian change (48 and 72-h bleed periods) indicated that, of the four hormones, only concentrations of α-MSH changed with a significant circadian periodicity. A significant circadian component of period length 24–25 h was detected in 37% (seven of 19) of cats examined. Concentrations of α-MSH were greatest coincident with or shortly after the onset of darkness. These findings indicate that pituitary–adrenocortical hormones are secreted episodically in domestic cats and that, in contrast to the patterns shown by ACTH and cortisol, secretion of the pars intermedia product α-MSH occurs with a circadian rhythm in about one-third of cats.

Robert J Kemppainen, Department of Physiology & Pharmacology, Auburn University College of Veterinary Medicine, Auburn, Alabama 36849, USA
Dopamine increases interleukin 6 release and inhibits tumor necrosis factor release from rat adrenal zona glomerulosa cells in vitro
Authors: Ritchie Paul K , Ashby Marilyn , Knight Heather H , Judd Allan M
Published: December 2008

Ritchie PK, Ashby M, Knight HH, Judd AM. Dopamine increases interleukin 6 release and inhibits tumor necrosis factor release from rat adrenal zona glomerulosa cells in vitro. Eur J Endocrinol 1996:134:610–6. ISSN 0804–4643

Interleukin 6 (IL-6) and tumor necrosis factor (TNF) are released from the zona glomerulosa of rat adrenal glands. The release of these cytokines from adrenal cells is regulated by interleukin 1β (IL-1β) and lipopolysaccharide (LPS), which are involved in the immune and inflammatory responses. Adrenocorticotropic hormone (ACTH) and angiotensin II, hormones that regulate the adrenal cortex, likewise regulate release of cytokines from adrenal glands. Dopamine inhibits aldosterone release from the adrenal cortex. Therefore, effects of dopamine on IL-6 and TNF release from rat adrenal zona glomerulosa were investigated. Primary cultures of rat adrenal zona glomerulosa cells were exposed to test agents and IL-6 and TNF release determined by the 7TD1 and WEHI bioassays, respectively. Dopamine increased basal IL-6 release and potentiated IL-6 release stimulated by ACTH, LPS or IL-1β. Dopamine inhibited basal and secretagogue-stimulated (LPS and IL-1β) TNF release. These effects of dopamine were mediated by D2 receptors because N-04 37, a D2 agonist, had effects on TNF and IL-6 release identical to those of dopamine. Therefore, dopamine, through D2 receptors, regulates the release of IL-6 and TNF from adrenal cells. Because TNF and IL-6 regulate adrenal steroid release, these cytokines may serve as autocrine or paracrine mediators of adrenal gland function.

Allan M Judd, Department of Zoology, Brigham Young University, Provo, UT 84602, USA
Stimulation of thyroid cell proliferation by epidermal growth factor is different from cell growth induced by thyrotropin or insulin-like growth factor I
Authors: Bechtner Günther , Schopohl Dorothee , Rafferzeder Michael , Gärtner Roland , Welsch Ulrich
Published: December 2008

Bechtner G, Schopohl D, Rafferzeder M, Gärtner R, Welsch U, Stimulation of thyroid cell proliferation by epidermal growth factor is different from cell growth induced by thyrotropin or insulin-like growth factor I. Eur J Endocrinol 1996;134:639–48. ISSN 0804–4643

Isolated intact porcine thyroid follicles free of contaminating single cells were embedded in "Matrigel". which is a gel-forming basement membrane preparation containing mainly collagen type IV, laminin, heparan sulfate proteoglycans and entactin. Follicles were treated with different growth factors: thyrotropin (TSH), insulin-like growth factor I (IGF-I), epidermal growth factor (EGF) or transforming growth factor beta. Cell proliferation was quantified by counting cell numbers. Morphological studies were done by photodocumentation and analysis of histology by light and electron microscopy. The thyrocytes had the physiological polarity with follicular cell arrangement, microvilli at the apical membrane, desmosomes and tight junctions. The lumen contained colloid. Iodide organification (10.2 ± 2.1 vs 26.1 ± 5.8 pmol/106 cells; TSH 0.1 mU/ml) and release of thyroid hormones thyroxine, 1754 ± 207 vs 2890 ± 460 pg/106 cells; triiodothyronine. 164 ± 22 vs 412 ± 106 pg/106 cells; TSH, 1 mU/ml) were significantly stimulated by TSH. There was no basal growth rate in serum-free medium but proliferation was slightly stimulated with TSH (1 mU/ml;149 ± 19%) and in the same order of magnitude with IGF-I (10 ng/ml; 159 ± 23%) but without follicle neoformation. In contrast, EGF (1.0–5.0 ng/ml) induced thyrocyte proliferation dose dependently three- to sixfold. With EGF up to 2 ng/ml, buds of new follicles formed surrounding pre-existing follicles. With EGF higher than 3 ng/ml, typical papillary structures developed. Transforming growth factor beta inhibited this dedifferentiated growth. A migration of single cells into the gel was never observed. Thus, three-dimensional culture of isolated thyroid follicles in "Matrigel" provides a tool for investigating the regulation of follicular growth and neoformation close to the in vivo situation.

G Bechtner, Medizinische Klinik, Klinikum Innenstadt, Ludwig-Maximilians-Universität München, Ziemssenstraße 1, 80336 München, Germany
Analysis of vasopressin receptor type II (V2R) gene in three Japanese pedigrees with congenital nephrogenic diabetes insipidus: identification of a family with complete deletion of the V2R gene
Authors: Jinnouchi Hideaki , Araki Eiichi , Miyamura Nobuhiro , Kishikawa Hideki , Yoshimura Ryohei , Isami Satoshi , Yamaguchi Kohei , Iwamatsu Hiroko , Shichiri Motoaki
Published: December 2008

Jinnouchi H, Araki E, Miyamura N, Kishikawa H, Yoshimura R, Isami S, Yamaguchi K, Iwamatsu H, Shichiri M. Analysis of vasopressin receptor type II (V2R) gene in three Japanese pedigrees with congenital nephrogenic diabetes insipidus: identification of a family with complete deletion of the V2R gene. Eur J Endocrinol 1996;134:689–98. ISSN 0804–4843

To investigate the association of mutations in the arginine vasopressin receptor type II (V2R) gene with congenital nephrogenic diabetes insipidus (CNDI) in the Japanese, we analyzed the V2R gene, located on the X chromosome, in three Japanese pedigrees with CNDI. In one pedigree, a large deletion spanning the entire coding region of the V2R gene was identified. In another pedigree, a G to A transition responsible for a substitution of Met88 (ATG) for Val88 (GTG) was detected. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis revealed that this was a de novo mutation that had occurred in the proband's mother. Because CNDI was observed only in those with this mutation, the pathogenicity of this mutation seemed clear. In the last pedigree, only a silent mutation at Leu309 (CTA→CTG) was found. All the individuals studied in this pedigree by allele-specific oligonucloetide-polymerase chain reaction (ASO-PCR) analysis showed a complete association of this mutation to the clinical symptoms. Because the silent mutation detected was unlikely to be a direct cause of CNDI. mutations in other regions of the V2R gene, such as a promoter region or other regulatory regions, may be responsible for the cause of CNDI in this pedigree. Thus, association of the V2R gene abnormality to clinical symptoms of CNDI was confirmed in three Japanese pedigrees, and a strong contribution of the V2R gene mutation to the development of CNDI was suggested.

E Araki, Department of Metabolic Medicine, Kumamoto University School of Medicine, 1-1-1 Honjo, Kumamoto 860, Japan
Desensitization from long-term intranasal treatment with hexarelin does not interfere with the biological effects of this growth hormone-releasing peptide in short children
Authors: Klinger Beatrice , Silbergeld Aviva , Deghenghi Romano , Frenkel Jenny , Laron Zvi
Published: December 2008

Klinger B, Silbergeld A, Deghenghi R, Frenkel J, Laron Z. Desensitization from long-term intranasal treatment with hexarelin does not interfere with the biological effects of this growth hormonereleasing peptide in short children. Eur J Endocrinol 1996;134:716–9. ISSN 0804–4643

A clinical, prospective experiment was carried out to determine whether long-term intranasal administration of the growth hormone-releasing peptide hexarelin (His-d-2-methyl-Trp-Ala-Trp-d-Phe-Lys-NH2) affects pituitary growth hormone secretion. Hexarelin (60 μg/kg t.i.d.) was administered to seven prepubertal constitutionally short children (mean age ±sd = 7.6 ± 2.4 years). Serum human growth hormone (hGH) response to an intranasal (20 μg/kg) and intravenous (1 μg/kg) bolus of hexarelin before, during and after 6–10 months of treatment was measured. The mean (±sd) peak rise of hGH to the intranasal bolus before treatment was 70.6 ± mU/I. After 7 days of hexarelin treatment, mean peak values dropped to 34.1 ±15.7 mU/l (p < 0.002) and thereafter remained constant for 6 months of treatment at 37.5 10.3 ±mU/l (p < 0.03). The pretreatment peak to the iv hexarelin bolus was 84.8 52.5 ±mU/l, and at the end of the treatment period it was 19.8 10.9 ±mU/l (p < 0.05). Three months after stopping treatment the mean (±sd) hGH response rose to 42.1 ±4.7 mU/l (p < 0.005). Growth velocity increased from 5.3±0.9 cm/year (before treatment) to 7.4 1.6 cm/year at ±6–10 months of treatment (p < 0.005). In conclusion, the partial suppression of pituitary hGH responsiveness to long-term intranasal hexarelin treatment, probably due to desensitization, does not affect the observed increase in growth velocity.

Z Laron, Pediatric Endocrinology, 11 El Al Street, Ramat Efal, 52960, Israel
Hormonal regulation of human protein metabolism
Authors: De Feo Pierpaolo
Published: December 2008

De Feo P. Hormonal regulation of human protein metabolism. Eur J Endocrinol 1996:135:7–18. ISSN 0804–4643

This review focuses on the effects of hormones on protein kinetics in humans. Most of the recent knowledge on the regulation of protein metabolism in humans has been obtained by tracing protein kinetics in vivo, using labelled isotopes of essential or non-essential amino acids. This technique allows the rates of the whole-body protein synthesis and breakdown to be estimated together with amino acid oxidation and the fractional synthetic rates of mixed muscle proteins or of single plasma proteins. Changes induced within these parameters by hormonal administration or endocrine diseases are also discussed. Hormones, on the basis of their net effect on protein balance (protein synthesis minus protein breakdown), are divided into two categories: those provided with an anabolic action and those with a prevalent catabolic action. The effects on protein metabolism of the following hormones are reviewed: insulin, growth hormone, IGF-I, adrenaline, androgens, estrogens, progesterone, glucagon, glucocorticosteroids, thyroid hormones. The review concludes with a report on the effects of multiple hormonal infusions on whole-body protein kinetics and a discussion on the potential role played by the concomitant increase of several hormones in the pathogenesis of protein wasting that complicates stress diseases.

Pierpaolo De Feo, DIMISEM, Via E. Dal Pozzo, 06126 Perugia, Italy
Activated and interferon-γ producing thyroid-derived T cells are detected in Graves' disease, thyroid autonomy as well as in non-toxic multinodular goiter
Authors: Aust Gabriela , Lehmann Irina , Laue Sandy , Scherbaum Werner A
Published: December 2008

Aust G, Lehmann I, Laue S, Scherbaum WA. Activated and interferon-γ producing thyroid-derived T cells are detected in Graves' disease, thyroid autonomy as well as in non-toxic multinodular goiter. Eur J Endocrinol 1996;135:60–8. ISSN 0804–4643

The relative numbers of activated and interferon gamma (IFN-γ)-producing peripheral blood lymphocytes (PBL) and thyroid-derived lymphocytes (TL) were determined using double surface and intracellular labeling techniques in flow cytometry. Cells were analyzed from 10 patients with Graves' disease (GD), eight patients with thyroid autonomy (TA) and five patients with non-toxic multinodular goiter (NTG). A maximum of 1% IFN-γ+ cells were detected both in unstimulated PBL and TL. Stimulation caused a two- to threefold higher number of IFN-γ+ cells in TL (GD, 48 ± 12%; TA, 48 ± 11%; NTG, 50± 15%) as compared to PBL (GD, 15 ± 7%: TA, 16 ± 8%; NTG, 18 ± 10%) of the same patients. Nearly all IFN-γ+ TL in GD were CD3+ T cells, whereas 10–20% of IFN-γ+ TL in TA and NTG were NK cells. In PBL 80% and in TL almost 100% of IFN-γ+ cells were antigenprimed CD45RO+ cells. Only 25–35% of IFN-γ+ thyroid-derived T cells expressed the CD4 antigen. About 42 ± 10% thyroid-derived T cells in GD, 33 ± 11% in TA and 34 ± 13% in NTG expressed the HLA-DR molecule but not the interleukin 2 (CD25) or the transferrin receptor (CD71). Forty per cent of these HLA-DR+ T cells showed an intracellular staining for IFN-γ and half of them co-expressed the activation antigen CD69. Immunofluorescence double labeling on thyroid cryostat sections demonstrated that HLA-DR+ T cells were also present in situ. The presence of activation antigens on thyroid-derived T cells not only in patients with GD but also in TA and NTG suggests failsafe mechanisms such as anergy, suppression or cytokine regulation in so-called non-immunogenic goiter.

Gabriela Aust, Department of Internal Medicine III, Endocrinology, University of Leipzig, Ph.-Rosenthal-Str. 27, Leipzig, D-04103, Germany
Relationships between plasma thyrotropin receptor antibodies and lipid or lipoprotein parameters in Graves' disease
Authors: Rieu Max , Revue Eric , Bonete Rémi , Nunez Sébastien
Published: December 2008

Rieu M, Revue E, Bonete R, Nunez S. Relationships between plasma thyrotropin receptor antibodies and lipid or lipoprotein parameters in Graves' disease. Eur J Endocrinol 1996:135:77–81. ISSN 0804–4643

Functional thyrotropin receptors (TSH-R) have recently been detected in fat cells but not in liver cells from rat, and it seems that in infant adipocytes stimulatory TSH-R antibodies (TSH-R-ab) act through this receptor pathway, resulting in increased triglyceride catabolism. We investigated the relationships between plasma TSH-R-ab and free thyroxine (FT4) levels and plasma lipid or lipoprotein values in 49 untreated adult women with Graves' disease, all positive for these antibodies. A simple positive correlation (p < 0.01) was found between TSH-R-ab levels and FT4 values (r = 0.40). Simple positive correlations (p < 0.001) were found between triglyceride levels and FT4 (r = 0.51) or TSH-R-ab (r = 0.52) values. Multiple regression analysis confirmed that both FT4 and TSH-R-ab are strong (p < 0.005) predictors of triglyceride (FT4: partial r = 0.40; TSH: partial r = 0.39). Simple negative correlations (p < 0.05, at least) were found between FT4 levels and total cholesterol (TC) (r = −0.45), low-density lipoprotein (LDL)-C (r = -0.46), apoprotein (apo)-B (r = −0.31) or high-density lipoprotein (HDL)-C (r = −0.55) values. Among these lipid parameters, only HDL-C levels (r = −0.31, p < 0.05) correlated to TSH-R-ab values. However, multiple regression analysis revealed that while FT4 is a strong predictor (p < 0.005) of TC (partial r = −0.42), LDL-C (partial r = −0.43) or HDL-C (partial r = 0.47), TSH-R-ab are not. Thus, the apparent positive relationship between TSH-R-ab and HDL-C results from the positive correlation between TSH-R-ab and FT4. In conclusion, this study suggests that stimulating TSH-R-ab are involved in triglyceride metabolism. In contrast to thyroid hormones, these antibodies seem not to be related to cholesterol metabolism.

Max Rieu, Hôpital Saint Michel, 33 rue Olivier de Serres, 75015 Paris, France
Evaluation of growth hormone (GH) responses to pulsed GH-releasing hormone administration using the MTT–ESTA bioassay
Authors: Dattani Mehul T , Winrow Andrew P , Tuil'Pakov Anatoly , Pringle P Jane , Hindmarsh Peter C , Brook Charles GD , Marshall Nicholas J
Published: December 2008

Dattani MT, Winrow AP, Tuil'Pakov A, Pringle PJ, Hindmarsh PC, Brook CGD, Marshall NJ. Evaluation of growth hormone (GH) responses to pulsed GH-releasing hormone administration using the MTT–ESTA bioassay. Eur J Endocrinol 1996;135:87–95. ISSN 0804–4643

We compared the immunoactivity of human growth hormone (hGH) with its bioactivity after stimulation of hGH release into the circulation by the administration of growth hormone-releasing hormone [GHRH(1–29)-NH2] according to a pre-determined protocol to four normal adult volunteers. We used the Hybritech immunoradiometric assay to measure the immunoactive GH concentrations. Bioactive GH concentrations were measured using the highly quantitative and precise eluted stain bioassay system (ESTA). The high sample capacity of the ESTA bioassay permitted us to monitor the bioactivities in closely timed sequential samples, and in far greater detail than has previously been possible. Two pulses of GHRH(1–29)-NH2 were administered intravenously to the four adult male volunteers (aged 24–37 years) on a weekly basis over a 4-week period. Two different doses of GHRH(1–29)-NH2 (0.1 and 1.0 μg/kg) were tested. These were separated by specified time intervals (60 or 120 min). Responses in the four individuals were variable. However, although the immunoand bioactivities generally agreed well, there was a systematic and progressive increase in the bioactivity/immunoactivity (B/I) ratios as half of the response peaks were approached. After these peak concentrations, the B/I ratios subsequently returned to values that were close to unity. The enhanced bioactivity of the peak samples from the two volunteers in whom the largest magnitudes of response were observed was found to be labile after long-term storage at −20°C. We suggest that the preferential rise in GH bioactivity, as opposed to immunoactivity, in response to GHRH(1–29)-NH2 was due to progressive changes in the concentrations of isoforms of GH that are not detectable in the Hybritech immunoassay.

NJ Marshall, Division of Molecular Pathology, University College London, The Windeyer Building, 46 Cleveland Street, London W1P 6DB, UK
Regulation of testicular anti-Müllerian hormone secretion
Authors: Rey Rodolfo , Josso Nathalie
Published: December 2008

Rey R, Josso N. Regulation of testicular anti-Müllerian hormone secretion. Eur J Endocrinol 1996; 135:144–52. ISSN 0804–4643

Anti-Müllerian hormone (AMH) is a glycoprotein secreted by Sertoli cells from the time of testicular differentiation and is responsible for the regression of Müllerian ducts in the male fetus. The chronology of AMH expression is very important because Müllerian ducts lose their responsiveness a few days after AMH secretion begins, which suggests that the AMH gene is under precise transcriptional control. Steroidogenic factor 1 (SF-1) is the only transcriptional regulator with demonstrated action on AMH expression. Although necessary for AMH expression, SF-1 alone is not sufficient to induce AMH transcription. SRY expression is turned on in Sertoli cells just before AMH expression is initiated, but the effective implication of SRY in AMH regulation remains unclear. During puberty, AMH expression is regulated negatively by androgens and declines dramatically in seminiferous tubules with meiotic development. Low serum AMH levels are observed in both central and gonadotropin-independent precocious puberty, which suggests that gonadotropins do not downregulate AMH at puberty. Serum AMH returns to normal infantile values 3–6 months after treatment. The absence of androgen response elements on the AMH promoter and the slow response to androgen withdrawal suggest that androgen regulation of AMH secretion is indirect. In patients with defects of androgen production or action, serum AMH reaches abnormally high levels in the neonatal and pubertal periods, which suggests a possible stimulatory role for gonadotropins that could be observed only in the absence of suppressive effects of androgens.

Rodolfo Rey, INSERM U.293, Ecole Normale Supérieure, 1 rue Maurice Arnoux, 92120 Montrouge, France
Regional comparison of prolactin gene expression in the human decidualized endometrium in early and term pregnancy
Authors: Tanaka Soichiro , Koibuchi Noriyuki , Ohtake Hideki , Ohkawa Hiroshi , Kawatsu Takeshi , Tadokoro Nozomu , Kumasaka Takahiro , Inaba Noriyuki , Yamaoka Sadao
Published: December 2008

Tanaka S, Koibuchi N, Ohtake H, Ohkawa H, Kawatsu T, Tadokoro N, Kumasaka T, Inaba N, Yamaoka S. Regional comparison of prolactin gene expression in the human decidualized endometrium in early and term pregnancy. Eur J Endocrinol 1996;135:177–83. ISSN 0804–4643

Prolactin (PRL) is known to be expressed in the decidualized human endometrium and secreted into amniotic fluid. Although the site of synthesis of endometrial PRL is known to be the decidual cells, the difference in PRL gene expression within each area of decidua, i.e. decidua basalis, decidua parietalis and decidua capsularis, during pregnancy is not clear. We have applied an in situ hybridization histochemistry technique using a radiolabeled RNA probe to compare the difference in expression of PRL gene within each area of the decidualized endometrium. Specific hybridization signals were distributed over the decidual cells in early and term pregnancy. More intense hybridization signals were always detected in the tissues of early pregnancy than in those of term pregnancy. In the decidua capsularis of early pregnancy, labeled cells were concentrated close to the amniotic cavity, whereas cells were concentrated close to the maternal surface of the fetal membrane in term pregnancy. In the decidua parietalis, almost all decidual cells were labeled, but no specific labeling was seen in the endometrial glands or capillary endothelium in both groups. In the decidua basalis, most decidual cells showed hybridization signals whereas no hybridization signal was seen over the trophoblast cells. These results show that there are regional and periodic differences in PRL gene expression in the decidual cells during pregnancy.

Noriyuki Koibuchi, Department of Physiology, Dokkyo University School of Medicine, Mibu, Tochigi 321-02, Japan
Decreasing melatonin and 6-hydroxymelatonin sulfate excretion with advancing gestational age in preterm and term newborn male infants
Authors: Commentz JC , Henke A , Dammann O , Hellwege HH , Willig RP
Published: December 2008

Commentz JC, Henke A, Dammann O. Hellwege HH, Willig RP. Decreasing melatonin and 6-hydroxymelatonin sulfate excretion with advancing gestational age in preterm and term newborn male infants. Eur J Endocrinol 1996;135:184–7. ISSN 0804–4643

We investigated the ontogeny of melatonin synthesis during fetal maturation by measuring the melatonin (MLT) and 6-hydroxymelatonin sulfate (MLTS) excretion in the urine of male infants aged 2–7 days and gestational age 26–42 weeks. We found a negative correlation between advancing gestational age and the MLT and MLTS excretion expressed as total 24-h amount, ratio of 24-h amount to creatinine and ratio of 24-h amount to body surface area. The ratio of MLT to MLTS was found to be about ten times higher in the study group than in prepubertal children, which might reflect the immaturity of hepatic sulfation capacities. The total amount of excreted MLT and MLTS was only one-tenth the prepubertal values. No day/night differences in MLT and MLTS excretion could be detected. We conclude that the fetal pineal gland is capable of a limited melatonin synthesis from the 26th week of gestation onwards, with decreasing values reaching its nadir around term. This indicates that the amount of fetal MLT excretion is not determined by synthesizing capacities of the pineal gland but by the development of neural connections to the pineal gland.

JC Commentz, Department of Pediatrics UKE, University of Hamburg, Martinistrasse 52, D-20246, Hamburg, Germany
Decrease in melatonin precedes follicle-stimulating hormone increase during perimenopause
Authors: Vakkuri Olli , Kivelä Aarre , Leppäluoto Juhani , Valtonen Maija , Kauppila Antti
Published: December 2008

Vakkuri O, Kivelä A, Leppäluoto J, Valtonen M, Kauppila A. Decrease in melatonin precedes folliclestimulating hormone increase during perimenopause. Eur J Endocrinol 1996;135:188–92. ISSN 0804–4643

Melatonin, the hormone of the pineal gland, which in animal studies has been found to inhibit aging processes, is secreted in smaller amounts towards senescence. Menopause, an aging process in women, is known to be associated with typical changes in gonadotropin and sex steroid secretion. Our main objective was to study the possible role of melatonin in the hormonal regulation of menopause. This study focused on detailed changes in melatonin and follicle-stimulating hormone (FSH) secretion cross-sectionally in pre- to postmenopausal females. Special attention was paid to females aged around 50 years, which is the mean menopausal age. Seventy-seven healthy female volunteers aged 30–75 years were the subjects of this study. Melatonin was measured radioimmunologically from nocturnal urine collected between 20.00 and 08.00 h, and FSH and melatonin from blood samples taken at 09.00 h. Nocturnal urinary excretion of melatonin was found to decline significantly from premenopause to postmenopause. The youngest premenopausal women (age group 30–39 years) excreted the highest amounts of melatonin (21.1 ± 2.2 pmol/h, mean±sem, N = 17). In the age group 40–44 years the excretion declined by 41% (p < 0.05). The second significant decline (35%, p < 0.05) took place between the age groups 50–54 years and 55–59 years. A declining trend as a function of age was also seen in morning serum melatonin. Serum FSH rose sharply to high levels before the age of 50 (p < 0.01) and remained at a high level thereafter. Urinary melatonin correlated negatively with serum FSH (r = −0.32. p < 0.05). In conclusion, the inverse changes in melatonin and FSH secretion during the perimenopausal years, with the sharpest decline in nocturnal excretion of melatonin far before menopause, suggest that melatonin may be permissively linked to the initiation of menopause.

O Vakkuri. Department of Physiology. University of Oulu, Kajaanintie 52 A, 90220 Oulu, Finland
Testosterone-induced increase of insulin-like growth factor I levels depends upon normal levels of growth hormone
Authors: Saggese Giuseppe , Cesaretti Graziano , Franchi Giulia , Startari Luisa
Published: December 2008

Saggese G, Cesaretti G, Franchi G, Startari L. Testosterone-induced increase of insulin-like growth factor I levels depends upon normal levels of growth hormone. Eur J Endocrinol 1996;135:211–5. ISSN 0804–4643

Pubertal development is associated with a rise in plasma insulin-like growth factor I (IGF-I) levels that is related both to the increase in sex steroids and/or to the sex steroid-induced augmentation in endogenous growth hormone (GH) secretion. In order to investigate the relationship between IGF-I. GH and testosterone, we examined 42 male subjects with various clinical conditions (classical GH deficiency (CGHD, N = 5), non-classical GH deficiency (NCGHD, N = 7), short idiopathic stature (N = 6), nutritional obesity (N = 8), GH-treated CGHD (N = 4), GH-treated NCGHD (N = 5) and normal stature (N = 7)) in which, for evaluation of hypogonadism (i.e. the absence of one or both testes from the scrotal sac), human chorionic gonadotropin (hCG) tests were performed. We measured IGF-I, total and free testosterone and dehydroepiandrosterone sulfate (DHEAS) by radioimmunoassays before and 48 and 96 h after the start of the test. The values of IGF-I were lower (0.001 < p < 0.005) in CGHD and NCGHD than in the other groups. In comparison to basal levels, IGF-I values increased (0.005 < p < 0.05) both 48 and 96 h after the start of the hCG test in short idiopathic and normal stature children and in GH-treated subjects with NCGHD, but only 96 h in subjects with untreated NCGHD and GH-treated CGHD. No difference was demonstrated in basal values of total testosterone among any of the groups, while basal free testosterone levels were higher (0.001 < p < 0.05) in GH-treated subjects with NCGHD than in all the other groups except nutritional obesity; furthermore, free testosterone was higher (p < 0.05) in nutritional obesity than in CGHD. The values of total and free testosterone obtained both 48 and 96 h after the start of the hCG test were higher (0.001 < p < 0.05) than basal values in all groups. The DHEAS values did not show any significant change during the hCG test. Basal values were higher (0.01 <p < 0.05) in nutritional obesity than in the other groups. Considering all groups, chonological age, bone age and bone age/chronological age ratio were correlated with basal free testosterone, IGF-I and DHEAS levels (0.001 < p < 0.05), while basal free testosterone and IGF-I values were correlated with DHEAS levels (p < 0.005 and <0.01, respectively). In conclusion, our study during the hCG test in boys with various clinical conditions demonstrated an increase in IGF-I concentrations only in those boys with sufficient GH secretion or GH replacement therapy. These findings indicate that both sex steroids and GH are necessary to allow for the pubertal increase in IGF-I levels.

Giuseppe Saggese, Endocrine Unit, Department of Pediatrics, University of Pisa, Via Rome 67, 56125 Pisa, Italy
Thyroxine binding to transthyretin (TTR) variants—two variants (TTR Pro 55 and TTR Met 111) with a particularly low binding affinity
Authors: Almeida Maria Rosário , Saraiva Maria João
Published: December 2008

Almeida MR, Saraiva MJ. Thyroxine binding to transthyretin (TTR) variants—two variants (TTR Pro 55 and TTR Met 111) with a particularly low binding affinity. Eur J Endocrinol 1996;135:226–30. ISSN 0804–4643

Thyroxine (T4) binding is a well-characterized function of transthyretin (TTR) and has been used to assess structural alterations of TTR variants. Most TTR variants deposit as amyloid fibrils originating different forms of hereditary amyloidosis. It has been hypothesized that amino acid substitutions in the TTR variants induce structural alterations that may be responsible for the amyloidogenicity of the mutant proteins. To test for structural alterations in TTR, we studied T4 binding to TTR variants both in whole serum and in isolated form obtained from heterozygotic carriers of amyloidogenic and non-amyloidogenic variants and compared the binding with the corresponding homozygotic recombinant variants. The results obtained indicated a normal T4 binding affinity for heterozygotic TTR Ala 49, TTR Leu 68, TTR Ala 71 and TTR Arg 102. Concerning TTR Pro 55 and TTR Met 111, we found a consistent decrease in binding affinity. These results were more pronounced for the equivalent recombinant proteins. Recombinant TTR Pro 55 did not show specific binding to T4 and recombinant TTR Met 111 presented very low binding affinity. Neither TTR Pro 55 nor TTR Met 111 are localized in the T4 binding channel, thus structural alterations induced by these mutations should be transmitted to the binding channel interfering with T4 binding. The results now reported, together with ongoing structural data by X-ray analyses on mutants Pro 55 and Met 111 and future binding studies with other ligands, will contribute to the elucidation of the structure and function of TTR, particularly in thyroid hormone metabolism.

Maria João Saraiva, Centro de Estudos de Paramiloidose, Hospital de Santo António, 4050 Porto, Portugal
Technical and clinical validation of a new immunoradiometric assay for human osteocalcin
Authors: Dumon JC , Wantier H , Mathieu F , Mantia M , Body JJ
Published: December 2008

Dumon JC, Wantier H, Mathieu F, Mantia M, Body JJ, Technical and clinical validation of a new immunoradiometric assay for human osteocalcin. Eur J Endocrinol 1996;135:231–7. ISSN 0804–4643

The measurement of circulating osteocalcin or bone GLA protein (BGP) constitutes a well established and non-invasive means for evaluating preferentially the bone formation rate, but most available commercial assays suffer from several technical constraints, notably a rapid degradation of BGP at room temperature or after thawing and the inability to measure subnormal values. We evaluated, from a technical and a clinical viewpoint, a newly available two-site sandwich immunoradiometric assay (IRMA) using standards of human origin and two different monoclonal antibodies. The theoretical and functional assay detection limit was 0.3 ng/ml. Concentrations of BGP progressively decreased when the serum was left at 4°C or at room temperature (mean apparent loss of 15% after 24 h). Two cycles of freezing–thawing only slightly reduced the BGP concentrations. The mean (± sd) BGP concentration was 19.6 ± 7.9 ng/ml in healthy subjects (NI, N = 61); the normal range was 8.1–35.6 ng/ml. There was a marked difference between pre- and postmenopausal women: 15.1 ±4.4 vs 22.3 ± 8.4 ng/ml, respectively (p<0.05). The mean BGP concentration in patients with tumor-induced hypercalcemia (N = 29) was not significantly different from NI, but nine patients (31%) had subnormal levels and five (17%) had elevated BGP levels. Concentrations of BGP were significantly increased in patients with hyperparathyroidism (N = 14) (45.1 ± 21.0 ng/ml) and significantly lower than NI in patients with hypoparathyroidism (N = 18) (7.3 ± 4.6 ng/ml). Concentrations of BGP were also measured by a classical radioimmunoassay using bovine standards and tracer; the correlations between both sets of measurements were significant in all groups, except in patients with hypoparathyroidism. In summary, this newly available IRMA for measuring circulating human BGP appears to be quite sensitive, reproducible and robust. It should be especially useful for investigating clinical conditions characterized by a low bone formation rate.

JJ Body, Institut Jules Bordet, Rue Héger-Bordet 1, 1000 Brussels, Belgium
11β-Hydroxysteroid dehydrogenase deficit: a rare cause of arterial hypertension. Diagnosis and therapeutic approach in two young brothers
Authors: Gourmelen Micheline , Saint-Jacques Irène , Morineau Gilles , Soliman Hany , Julien René , Fiet Jean
Published: December 2008

Gourmelen M. Saint-Jacques I, Morineau G. Soliman H, Julien R, Fiet J. 11β-Hydroxysteroid dehydrogenase deficit: a rare cause of arterial hypertension. Diagnosis and therapeutic approach in two young brothers. Eur J Endocrinol 1996;135:238–44. ISSN 0804–4643

We report the clinical history and results of endocrine investigations in two brothers born to consanguineous parents, who presented with hypokalemia and arterial hypertension when they were aged 2 and 6 years. The hormonal serum assay results, including extremely low values for aldosterone and plasma renin activity, favored the existence of apparent mineralocorticoid excess. A diagnosis of 11β-hydroxysteroid dehydrogenase (11β-HSD) deficiency was made, based on assays of the hydrogenated urinary metabolites of cortisol and cortisone, as well as of corticosterone and dehydrocorticosterone. Indeed we found a very low rate of urinary elimination of cortisone metabolites: tetrahydrogenated cortisone was reduced to between 0.10 and 30 μmol/24 h, which is 15–100 times lower than the normal rate; hexahydrogenated cortolones a and β were found to be 7-to 20-fold lower than normal levels; and the 11-keto-17-ketosteroid derivatives of cortisone were also reduced. Urinary elimination of the cortisol-reduced metabolites 5β- and 5α-tetrahydrogenated cortisol were slightly reduced or normal. These results argue in favor of a deficit in the enzyme 11β-HSD, which oxidizes cortisol into cortisone. A moderate defect in the conversion of cortisol into 5β-THF compared to normal conversion into 5α-THF was also found. With respect to corticosterone metabolism, we demonstrated the presence of a defect in the oxidation of that steroid into dehydrocorticosterone, also due to the deficit in 11β-HSD. Arterial hypertension and hypokalemia were corrected by treatment with dexamethasone, concomitantly with correction of the low aldosterone and plasma renin activity levels. On the other hand, during this treatment, urinary concentrations of the metabolites of cortisol. cortisone and corticosterone were only moderately affected.

Jean Fiet, Laboratoire de Biologie Hormonale, Hôpital Saint-Louis, I Avenue Claude Vellefaux, 75475 Paris Cedex 10, France
Hyponatraemia secondary to cerebral salt wasting syndrome following routine pituitary surgery
Authors: Atkin Stephen L , Coady Anne Marie , White Michael C , Mathew Bruce
Published: December 2008

Atkin SL, Coady AM. White MC, Mathew B. Hyponatraemia secondary to cerebral salt wasting syndrome following routine pituitary surgery. Eur J Endocrinol 1996;135:245–7. ISSN 0804–4643

A female aged 53 years was found to have a suprasellar lesion, which was shown to be a Rathke's cyst after removal by transsphenoidal surgery. She presented 16 days postoperatively, and following two grand mal seizures was found to be profoundly hyponatraemic (sodium 101 mmol/l). She was initially thought to have the syndrome of inappropriate antidiuretic hormone and was treated accordingly, but central venous pressure measurement revealed the hypovolaemia of cerebral salt wasting syndrome. The patient subsequently developed severe neurological sequelae after the correction of her hyponatraemia, following the development of extrapontine myelinolysis. Cerebral salt wasting syndrome is a rare cause of hyponatraemia following pituitary transsphenoidal surgery, which may mimic the syndrome of inappropriate antidiuretic hormone secretion. This case emphasizes the poor prognosis that may result from the rapid correction of profound hyponatraemia.

SL Atkin, Michael White Centre for Diabetes and Endocrinology, Royal Hull Hospitals, 220-236 Anlaby Road, Hull HU3 2RW, UK