bluuebunny/crossref_metadata_2025 huggingface dataset:
Thyroid hormone status and nutrient intake in the free-living elderly. Interest of reverse triiodothyronine assessment
Authors: Goichot B , Schlienger JL , Grunenberger F , Pradignac A , Sapin R
Published: December 2008

Goichot B, Schlienger JL, Grunenberger F, Pradignac A, Sapin R. Thyroid hormone status and nutrient intake in the free-living elderly. Interest of reverse triiodothyronine assessment. Eur J Endocrinol 1994; 130:244–52. ISSN 0804–4643

Fasting or hypocaloric diets are established methods of inducing low triiodothyronine (T3) levels that resemble the sick euthyroid syndrome in adults, but little is known on the mechanisms of this syndrome in the elderly. Decreasing T3 does not seem to be an unavoidable consequence of ageing, but the role of illness or other factors in this decline remains unclear. The aim of this work was to study the influence of nutritional factors on thyroid hormone levels in free-living elderly subjects. A 3-day dietary survey was conducted in 440 randomized subjects aged between 65 and 96. Cholesterol, apoproteins, prealbumin, hemoglobin, thyrotropin-free thyroxine (FT4), FT3 and reverse T3 (rT3) were assayed in each subject. Only 11 subjects had low FT3 levels, and they also had low levels of cholesterol, prealbumin and hemoglobin and a lower Folstein score compared to the rest of the population. Twenty-one subjects had isolated elevated rT3 levels, they were older and had significantly lower energy and fat intakes than the rest of the population. There was a clear reduction in FT3 levels and an increase in rT3 levels with age, although in the normal ranges, which occurred despite maintenance of a high-energy intake even in the oldest group. The FT3 level was lower in the subjects with poor health status, whereas high rT3 levels were associated with low energy intake in men. Stepwise regression showed that hemoglobin, age and prealbumin were the best predictors of FT3 levels, whereas age and energy intake were the main predictors of rT3 levels. Our results confirm the low prevalence of the low T3 syndrome in healthy elderly persons, and demonstrate the existence of another group of elderly subjects with isolated elevated rT3 levels. Whereas a low FT3 level seems to be associated with illness, rT3 is clearly associated with a low energy intake. Other studies are necessary to appreciate the specificity of this association and the usefulness of rT3 as an indication of nutrient intake.

JL Schlienger, Service de Médecine Interne, CHU Hautepierre, avenue Molière, 67098 Strasbourg Cedex, France
Stimulation of endothelin-1 production by thrombin, but lack of interference by high ambient glucose in vitro
Authors: Baumgartner-Parzer Sabina , Wagner Oswald , Nowotny Peter , Vierhapper Heinrich , Waldhäusl Werner
Published: December 2008

Baumgartner-Parzer S, Wagner 0, Nowotny P, Vierhapper H, Waldhäusl W. Stimulation of endothelin-1 production by thrombin, but lack of interference by high ambient glucose in vitro. Eur J Endocrinol 1994;130:271–5. ISSN 0804–4643

Diabetic vascular disease is associated with a state of hypercoagulability and altered endothelial properties, leading to elevated plasma levels of endothelium-derived peptides and proteins, e.g. endothelin-1. von Willebrand factor or fibronectin. This study determined dynamic immunoreactive endothelin-1 secretion by human umbilical vein endothelial cells exposed to thrombin (5 × 106 mU/l) in the presence (40 mmol/l) and absence (5.5 mmol/l) of excessive glucose in the cell culture medium. Exposure to high glucose and thrombin concentrations was initiated after cell confluency and applied for 24 h for measurements of endothelin-1 and for 2 and 5 h for the determination of preproendothelin-1, von Willebrand factor and fibronectin messenger ribonucleic acid. Comparisons were made versus cells incubated with normal glucose concentrations or with high mannose or NaCl concentrations as osmotic control. Neither preproendothelin-1, fibronectin and von Willebrand factor messenger ribonucleic acid expression nor endothelin-1 release was affected by high concentrations of glucose, mannose or sodium chloride.

Sabina Baumgartner-Parzer, Department of Medicine III, Division of Endocrinology and Metabolism, Währinger Gürtel 18-20, 1090 Vienna, Austria
Increased ratio between anaerobic and aerobic metabolism in lymphocytes from hyperthyroid patients
Authors: Valdemarsson Stig , Monti Mario
Published: December 2008

Valdemarsson S, Monti M. Increased ratio between anaerobic and aerobic metabolism in lymphocytes from hyperthyroid patients. Eur J Endocrinol 1994;130:276–80. ISSN 0804–4643

While an increased oxygen consumption is accepted as one consequence of hyperthyroidism, only few data are available on the role of anaerobic processes for the increased metabolic activity in this disease. In this study we evaluated the relative importance of anaerobic and aerobic metabolism for the metabolic activity in lymphocytes from patients before and after treatment for hyperthyroidism. Total lymphocyte heat production rate (P), reflecting total cell metabolic activity, was determined in a plasma lymphocyte suspension using direct microcalorimetry. The contribution from aerobic metabolism (O2 – P) was calculated from the product of the lymphocyte oxygen consumption rate and the enthalpy change for glucose combustion, and the anaerobic contribution as the difference between P and O2 – P. The total lymphocyte heat production rate P was 3.37 ± 0.25 (sem) pW/cell (N = 11) before and 2.50 ± 0.11 pW/cell (N = 10) after treatment for hyperthyroidism (p < 0.01) as compared to 2.32 ± 0.10 pW/cell in a control group (N = 18). The aerobic component O2 – P amounted to 1.83 ± 0.11 pW/cell in the patient group before and 1.83 ± 0.08 pW/cell after treatment and to 1.71 ± 0.16 pW/cell in 10 controls. Out of P, the O2 – P component corresponded to 56.8 ± 4.4% in the hyperthyroid state and to 73.7 ± 3.2% after treatment (p < 0.01) as compared to 73.4 ± 4.4% in the 10 euthyroid controls. It was concluded that the increased metabolic activity demonstrated in lymphocytes from hyperthyroid patients cannot be explained by an increased oxygen-dependent consumption. This suggests that cell function may be comparatively more dependent on anaerobic metabolism during thyroid hormone excess and that adenosine triphosphate generation thereby has to be supplied through an increased metabolism of energy-rich substrates along anaerobic metabolic pathways.

Stig Valdemarsson, Department of Internal Medicine, Lund University Hospital, S-221 85 Lund, Sweden
Cardiac triiodothyronine nuclear receptor binding capacities in amiodarone-treated, hypo- and hyperthyroid rats
Authors: Gotzsche Liv Bjorn-Hansen , Ørskov Hans
Published: December 2008

Gotzsche LBH, Ørskov H. Cardiac triiodothyronine nuclear receptor binding capacities in amiodaronetreated, hypo- and hyperthyroid rats. Eur J Endocrinol 1994;130:281–90. ISSN 0804–4643

Parameters that are assumed to be under direct control by thyroid hormonal state were evaluated in amiodarone-treated, hypo- and hyperthyroid rats. Special attention was paid to evaluating similarities between hypothyroid and amiodarone-treated rats, with special focus on myocardial nuclear triiodothyronine (T3) receptor binding characteristics. Rats were rendered hypothyroid by adding KCIO4 to the drinking water for 6 weeks (N = 14). Hyperthyroidism was induced by adding 0.003% l-thyroxine to the drinking water for 6 weeks (N = 14). Fourteen rats were treated orally for 6 weeks with amiodarone, whereas 14 rats served as untreated controls. Equilibrium binding characteristics for T3 nuclear receptors were determined by means of a simple and rapid method with excellent reproducibility and sensitivity. Body temperature and heart rate were lowered in hypothyroid and amiodarone-treated rats. Maximum binding capacities ofβ-adrenergic receptors were reduced by 39% and 14% (p < 0.05) in hypothyroid and amiodarone-treated rats, respectively, and increased by 28% (p < 0.05) in hyperthyroid rats. Maximum binding capacities for voltage-operated Ca2+ channels were increased by 35% and 16% in hypothyroid and amiodarone-treated rats (p < 0.05), respectively, and decreased by 24% in hyperthyroid rats (p < 0.05). Maximum binding capacities for T3 receptors (expressed per unit of DNA) were reduced by 39% and 32% in hypothyroid and amiodarone-treated rats (p < 0.05), respectively, and increased by 63% in hyperthyroid rats (p < 0.05). In hypothyroid and amiodarone-treated rats, myocardial T3 content was extremely reduced (less than 0.05 nmol/kg and 0.06 ± 0.08 nmol/kg, respectively, compared with control levels of 1.55 ± 0.46 nmol/kg). In vitro competition studies of amiodarone and its desethylanalogue revealed that both drugs are potentially capable of displacing T3 from its nuclear receptor at concentrations close to what are considered therapeutic drug levels. Myocardial nuclear T3 receptor maximum binding capacities decreased to a similar degree in hypothyroid and amiodarone-treated rats and increased in hyperthyroid rats. Several other similarities between hypothyroid and amiodarone-treated rats suggest that amiodarone may act by inducing a state of thyroid hormonal resistance.

Liv Bjørn-Hansen Gøtzsche, Medical Department (Diabetes and Endocrinology), Århus Kommunehospital, University Hospital of Århus, DK-8000 Århus C, Denmark
Centrally administered vasopressin modifies stress hormone (cortisol, prolactin) secretion in sheep under basal conditions, during restraint and following intravenous corticotrophin-releasing hormone
Authors: Matthews SG , Parrott RF
Published: December 2008

Matthews SG, Parrott RF. Centrally administered vasopressin modifies stress hormone (cortisol, prolactin) secretion in sheep under basal conditions, during restraint and following intravenous corticotrophin-releasing hormone. Eur J Endocrinol 1994;130:297–301. ISSN 0804–4643

The effects of central (lateral ventricle) injections of vasopressin (2.5, 25 or 250 ng) on cortisol and prolactin release were investigated in castrated male sheep (N = 6) under basal (non-stress) conditions, during 120 min of physical restraint and following peripheral injection of ovine corticotrophin-releasing hormone (oCRH). Cortisol and prolactin concentrations in non-stressed sheep were raised significantly (p < 0.05) in the 120 min following administration of 250 ng of vasopressin. The prolactin response to restraint stress was decreased (p < 0.05) in the 30-min period following central injection of 250 ng of vasopressin. The stimulatory effect of oCRH on cortisol release was enhanced (p < 0.05) by vasopressin (25 and 250 ng), whereas prolactin levels decreased (p < 0.02) in the 30-min period following injection of the highest dose of vasopressin. None of the central doses of vasopressin significantly altered plasma levels of this hormone, although vasopressin secretion was increased during restraint.

SG Matthews, Lawson Research Institute, 268 Grosvenor Street, London, Ontario N64 4V2, Canada
Involvement of autocrine mechanism of transforming growth factor-β in the functional differentiation of pregnant mouse mammary gland
Authors: Yamamoto Toshiya , Komura Hiroko , Morishige Ken-ichirou , Tadokoro Chikae , Sakata Masahiro , Kurachi Hirohisa , Miyake Akira
Published: December 2008

Yamamoto T, Komura H, Morishige K, Tadokoro C, Sakata M, Kurachi H, Miyake A. Involvement of autocrine mechanism of transforming growth factor-β in the functional differentiation of pregnant mouse mammary gland. Eur J Endocrinol 1994;130:302–7. ISSN 0804–4643

We studied the presence and possible role of the autocrine mechanism of transforming growth factor-β (TGF-β) in pregnant mouse mammary gland. Northern blot analysis revealed the expression of the TGF-β1 gene transcript at 2.5 kb in mammary epithelial cells isolated from virgin and mid-pregnant mice. The TGF-β activity was higher in the conditioned medium from mid-pregnant mouse mammary explants than that from virgin explants by a bioassay system using mink lung epithelial cells. A binding study using [125I]TGF-β1 as a ligand showed that pregnant mouse mammary epithelial cells possessed a single class of high-affinity TGF-β1 binding sites (Kd = 28.0 pmol/l, 1.2 × 104 sites per cell). These results suggested the presence of a TGF-β autocrine mechanism in pregnant mouse mammary epithelial cells. Next, we examined the effect of TGF-β1 on the functional differentiation of pregnant mouse mammary gland. Transforming growth factor-β1 inhibited α-lactalbumin production in cultured mammary explants from mid-pregnant mice in a dose-dependent manner without inhibiting DNA synthesis. All these results suggest that TGF-β may play a role in regulating the functional differentiation of mouse mammary glands during pregnancy.

Hirohisa Kurachi, Department of Obstetrics and Gynecology, Osaka University Medical School, 2-2 Yamadaoka, Suita, Osaka 565, Japan
Effects of rat corticotrophin-releasing factor, arginine vasopressin and oxytocin on the secretions of adrenocorticotrophic hormone and corticosterone in the fetal rat in late gestation: in vivo and in vitro studies
Authors: Deloof S , Montel V , Chatelain A
Published: December 2008

Deloof S, Montel V, Chatelain A. Effects of rat corticotrophin-releasing factor, arginine vasopressin and oxytocin on the secretions of adrenocorticotrophic hormone and corticosterone in the fetal rat in late gestation: in vivo and in vitro studies. Eur J Endocrinol 1994;130:313–19. ISSN 0804–4643

The effects of rat corticotrophin-releasing factor (rCRF), arginine vasopressin (AVP) and oxytocin (OT) were investigated in vivo in 21 -day-old rat fetuses injected through the umbilical vein and in vitro on perifused anterior pituitary glands from 21-day-old rat fetuses. In vivo, rCRF (1.25 pmol • 50 μl−1 • fetus−1), AVP (5 pmol • 50 μl−1 •fetus−1) alone and rCRF in association with AVP or oxytocin (12.5 pmol • 50 μl−1 • fetus−1) increased plasma adrenocorticotrophic hormone (ACTH) and corticosterone levels only 30 min after the start of injection. During the first 10 min of the sampling period, the injection of these peptides alone or in combination and the injection of saline decreased the plasma ACTH concentration, which was lower than that of uninjected fetuses, but had no effect on the plasma corticosterone concentration. In vitro, the release of ACTH by perifused anterior pituitary glands was increased strongly by rCRF (4 pmol/0.5 ml) but only slightly by AVP (92 pmol/0.5 ml) and oxytocin (198 pmol/0.5 ml). Arginine vasopressin and oxytoxin potentiated the release of ACTH stimulated by rCRF in vitro but not in vivo. Our results suggest that rCRF is the major peptide that controls ACTH secretion in the fetal rat at term. In conclusion, the rise of the ACTH level observed only 30 min after injection of rCRF or AVP suggests the existence of a factor able to inhibit the ACTH response after injection of these peptides. This factor might be elicited by the blood volume expansion.

A Chatelain, Laboratoire de Neuroendocrinologie du Développement, Université des Sciences et Technologies de Lille, Bâtiment SN4, 59655 Villeneuve d'Ascq cédex, France
Molecular prenatal exclusion of familial partial androgen insensitivity (Reifenstein syndrome)
Authors: Lumbroso Serge , Lobaccaro Jean-Marc , Belon Charles , Amram Serge , Bachelard Bruno , Garandeau Patrick , Sultan Charles
Published: December 2008

Lumbroso S, Lobaccaro J-M, Belon C, Amram S, Bachelard B, Garandeau P, Sultan C. Molecular prenatal exclusion of familial partial androgen insensitivity (Reifenstein syndrome). Eur J Endocrinol 1994;130:327–32. ISSN 0804–4643

In a large family with Reifenstein syndrome, we previously performed molecular analysis of the androgen receptor gene. Direct sequencing showed a G–A point mutation at position 2818 of exon 7, which was responsible for an arginine–histidine substitution at position 840 of the androgen receptor. In this family, the proband's mother became pregnant and wished to know whether she was carrying an unaffected fetus. Polymerase chain reactions of the sex-determining region of the Y chromosome (the SRY gene) on trophoblastic DNA at week 14 revealed a 46,XY genotype. Sequencing analysis showed the canonical sequence (CGT, encoding an Arg residue), suggesting that the fetus was not affected. The expectation of normal male sexual development was confirmed by detection of normal male external genitalia through ultrasonography at week 24. These data confirm that sequence analysis of the androgen receptor gene on trophoblastic DNA is the most reliable method for prenatally diagnosing or excluding androgen insensitivity syndrome in high-risk families.

Charles Sultan, Endocrinologie et Gynécologie Pédiatriques, Service de Pédiatrie I, Hôpital A. de Villeneuve, 34059 Montpellier Cedex, France
Secretory pattern of vasopressin in plasma and cerebrospinal fluid of patients with dementia and of two control groups
Authors: Nadal M , Wikström L , Ruthström L
Published: December 2008

Nadal M, Wikström L, Ruthström L. Secretory pattern of vasopressin in plasma and cerebrospinal fluid of patients with dementia and of two control groups. Eur J Endocrinol 1994;130:346–9. ISSN 0804–4643

Since the description of its antidiuretic effect in 1913, a variety of functions have been attributed to vasopressin, one of the most controversial throughout the years probably being its effect on memory processes. In an attempt to study the actual secretory rhythm of vasopressin in humans with demonstrated impaired memory, the plasma and cerebrospinal fluid levels of the peptide have been examined during 24 h in a group of patients with dementia, and their values compared with two healthy control groups of young and elderly volunteers. Patients with dementia had higher circulating levels of vasopressin in plasma than the healthy participants and the differences were statistically significant when compared with the healthy elderly (p = 0.003). This difference is not age-related because both groups were in the same age range. A possible explanation could be the higher plasma osmolality measured in the patients with dementia, despite the fact that their levels were within the normal ranges. The different results could not be attributed to changes in electrolytes or blood pressure because these parameters were similar in all groups (p = NS). But more interesting, perhaps, is the secretory pattern found in all three groups. The pattern is biphasic, with two significant peaks: at 16.00 h (p = 0.032) and at night (p = 0.002). This pattern was similar in all cases and in all groups. The total nocturnal secretion of vasopressin is higher than the diurnal secretion (p = 0.02) only in the plasma because the cerebrospinal fluid values were higher during the day. In contrast to plasma, no significant difference was found in the levels of vasopressin in cerebrospinal fluid between patients with dementia and the healthy groups. Furthermore, the correlation between plasma and cerebrospinal fluid levels was, as a whole, rather poor in our material but better in the healthy young volunteers. It seems evident, in view of these results, that the postulated relationship between vasopressin and memory cannot depend on an inadequate concentration of the hormone in the cerebrospinal fluid because all our groups showed similar values. Several hypotheses are given to explain the secretory pattern found in our material as well as for the differences in plasma between the patients with dementia and the control groups.

M Nadal, Skellefteå Hospital, 93187 Skellefteå, Sweden
Arginine vasotocin receptor binding in the hen uterus (shell gland) before and after oviposition
Authors: Takahashi Tetsuya , Kawashima Mitsuo , Kamiyoshi Michiharu , Tanaka Katuhide
Published: December 2008

Takahashi T, Kawashima M, Kamiyoshi M, Tanaka K. Arginine vasotocin receptor binding in the hen uterus (shell gland) before and after oviposition. Eur J Endocrinol 1994;130:366–72. ISSN 0804–4643

The binding affinity and capacity of arginine vasotocin (AVT) receptor in the hen uterus changed during a period before and after oviposition. Three hours before oviposition, the binding capacity of the AVT receptor increased. An injection of prostaglandin (PG) F2α caused an increase in the AVT receptor Bmax in the uterus, and indomethacin blocked the normal rise in the AVT receptor Bmax and PGF content prior to oviposition. However, just prior to oviposition, the binding affinity increased with a decrease in the binding capacity. A progesterone injection caused an increase in binding affinity and a decrease in binding capacity of the AVT receptor. The specific binding of the progesterone receptor in the uterus increased 2 h before oviposition and remained high until oviposition. Serum AVT levels increased at oviposition. An injection of AVT caused an increase in the affinity of the AVT receptor with a decrease in the capacity. The change in the affinity and capacity of AVT receptor at oviposition may result from the action of progesterone via increased progesterone receptor binding, and the action of AVT on its own receptors.

Michiharu Kamiyoshi, Department of Animal Production and Utilization Sciences, The United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu 501-11, Japan
Silent necrosis of a pituitary corticotroph adenoma revealed by timely magnetic resonance imaging: a cause of spontaneous remission of Cushing's disease
Authors: Le Nestour Elisabeth , Abécassis Jean-Paul , Bertagna Xavier , Bonnin André , Luton Jean-Pierre
Published: December 2008

Le Nestour E, Abécassis J-P, Bertagna X, Bonnin A, Luton J-P. Silent necrosis of a pituitary corticotroph adenoma revealed by timely magnetic resonance imaging: a cause of spontaneous remission of Cushing's disease. Eur J Endocrinol 1994;130:469–71. ISSN 0804–4643

Spontaneous necrosis of a corticotroph adenoma is rare and is a very unlikely way of curing Cushing's disease. We report hereafter a case where magnetic resonance imaging of the pituitary provided clear evidence of the event. Successive and timely pituitary magnetic resonance imaging in this patient showed first a typical microadenoma as a well-limited mass with a low signal intensity before the necrosis, then a bright signal before gadolinium injection in the T1-weighted image at the time of the event and, finally, the aspect of an empty sella turcica with a small arachnoidocele 1 year later. The necrosis of a corticotroph adenoma is more frequent in macro- than in microadenomas, and is usually heralded by headache and visual disturbances. In this case, pituitary necrosis was entirely asymptomatic, and cured the patient as well as the surgeon's knife would have. Nevertheless, this exceptional occurrence does not rule out the possibility of a recurrence.

X Bartagna, Clinique des Maladies Endocriniennes et Métaboliques, Hôpital Cochin, 27 rue due Faubourg Saint Jacques, 75014 Paris, France
Systemic iodine absorption during endoscopic application of radiographic contrast agents for endoscopic retrograde cholangiopancreaticography
Authors: Mann K , Rendl J , Busley R , Sailer B , Seybold S , Hoermann R , Sauerbruch T , Börner W
Published: December 2008

Mann K, Rendl J, Busley R, Sailer B, Seybold S, Hoermann R, Sauerbruch T, Börner W. Systemic iodine absorption during endoscopic application of radiographic contrast agents for endoscopic retrograde cholangiopancreaticography. Eur J Endocrinol 1994;130:498–501. ISSN 0804–4643

Hyperthyroidism induced by contrast agents is a major problem in patients with pre-existing thyroid disease, particularly in patients with functional thyroid autonomy. The present study was undertaken to evaluate whether contrast media applied during endoscopic retrograde cholangiopancreaticography (ERCP) may result in a significant increase of serum iodine levels and thus may be associated with the risk of iodine-induced hyperthyroidism. The courses of serum concentrations of total iodine and free iodide, as well as of urinary iodine excretion, were measured in 15 patients before and up to 21 days after ERCP. During ERCP, the non-ionic contrast medium iopamidol was instilled in amounts resulting in a total iodine load of 57.4 ± 22.8 mmol (7.3 ± 2.9 g). In all patients, ERCP resulted in a highly significant increase in serum levels of total iodine from 0.8±0.5 to 85.2 ± 116.9 μmol/l 4 h after application of the contrast agent. In parallel, serum iodide levels were raised from 0.06 ± 0.04 to 5.42 ± 6.09 μmol/l and urinary iodine excretion from 71.1 ± 35.7 μmol/mol creatinine to 621 620.9 ± 636 492.2 μmol/mol creatinine. Peak concentrations of serum iodine are well related to the total amount of iodine applied (p < 0.05). During follow-up, iodine levels returned to preexposure levels within 2–3 weeks. Levels of thyrotropin, free thyroxine, and free triiodothyronine remained unchanged during the follow-up period. In conclusion, endoscopic application of iodinated contrast agents during ERCP leads to significant increases of serum levels of total iodine and free iodide and of urinary iodine excretion. Therefore, patients with underlying thyroid disease may be at risk to develop iodine-induced hyperthyroidism.

Klaus Mann, Dept. of Internal Medicine II. Klinikum Grosshadern, Marchionistr. 15, 81377 Munich, Germany
Somatostatin in the boar reproductive system
Authors: Ødum Lars , Pildal Julie , Rehfeld Jens F
Published: December 2008

Ødum L, Pildal I. Rehfeld pJF. Somatostatin in the boar reproductive system. Eur J Endocrinol 1994;130:515–21. ISSN 0804–4643

Somatostatin (SRIF) is a widely distributed regulatory peptide. Recently, it was shown that human seminal plasma contains high concentrations of SRIF. In order to find the cellular source of seminal SRIF we have examined the presence of SRIF in porcine urogenital tissues. The concentration of SRIF in male accessory reproductive tissues of 3-month-old pigs (N = 4) ranged from 1 to 17 nmol/kg. In the boar, only the prostate gland contained significant amounts of SRIF (median 7 nmol/kg, range 3–18 nmol/kg, N = 4). Testis and semen contained no SRIF. Gel chromatography of extracts of the male accessory sex glands and epididymis showed both SRIF-28 and SRIF-14, whereas urinary bladder contained mainly SRIF-14. In conclusion, the results show a considerable species, tissue and developmental variation in the expression of SRIF in the genitourinary tract.

Lars Ødum, Department of Clinical Chemistry, Herlev Hospital, Herlev Ringvej 75, DK-2730, Denmark
Relation of attenuated proestrous luteinizing hormone surges in middle-aged female rats to in vitro pituitary gonadotropin-releasing hormone responsiveness
Authors: Brito Aurelia N , Sayles Timothy E , Krieg Richard J , Matt Dennis W
Published: December 2008

Brito AN, Sayles TE, Krieg Jr RJ, Matt DW. Relation of attenuated proestrous luteinizing hormone surges in middle-aged female rats to in vitro pituitary gonadotropin-releasing hormone responsiveness. Eur J Endocrinol 1994;130:540–4. ISSN 0804–4643

Prior to the cessation of regular cyclicity, middle-aged rats display pre-ovulatory luteinizing hormone (LH) surges of reduced magnitude. The present study was designed to identify whether middle-aged female rats with attenuated proestrous LH surges have alterations in pituitary responsiveness to gonadotropin-releasing hormone (GnRH). Young (4 months old) and middle-aged (10–12 months old) regularly cycling females were catheterized and sampled on proestrus to characterize their LH surge profiles. On the next proestrus (12.00 h), pituitaries were perifused individually and exposed to three pulses of GnRH (30 nmol/l). The patterns of the proestrous LH surges revealed that 12 of 22 middle-aged rats had attenuated surges (< 7 μg/l) while the remaining 10 middle-aged females had surges that were similar to those of young rats. Pituitaries perifused on the next proestrus showed similar basal LH release among the middle-aged and young females. However, the LH secretory rates following the second and third administration of GnRH, as well as the overall GnRH-stimulated LH secretory rates, were significantly decreased in middle-aged females with previously attenuated LH surges as compared to those from the young proestrous rats. In contrast, middle-aged rats with normal LH surges had pituitary LH responses that were no different from those of young females. These results indicate that a decrease in pituitary LH responsiveness to GnRH is only apparent in middle-aged rats that display attenuated proestrous LH surges.

Dennis W Matt. Department of Obstetrics and Gynecology, Medical College of Virginia, Box 980034, Richmond, VA 23298, USA
Prevention of iodine deficiency disorders by oral administration of lipiodol during pregnancy
Authors: Chaouki Mohamed L , Benmiloud Moulay
Published: December 2008

Chaouki ML. Benmiloud M. Prevention of iodine deficiency disorders by oral administration of lipiodol during pregnancy. Eur J Endocrinol 1994;130:547–51. ISSN 0804–4643

The prevalence of iodine deficiency disorders and the thyroid status of the population were studied in an endemic goitre area in Algeria. After oral administration of lipiodol (0.5 ml), three treated groups of mother–newborn couples were compared to an untreated group: group A, mothers treated 1–3 months before conception; group B, mothers treated during the first month of pregnancy; group C, mothers treated during the third month of pregnancy. Untreated mothers were used as a control (group D). After lipiodol treatment, all newborn babies and mothers were clinically euthyroid. All tested newborn babies were full term and no goitre was observed in the four groups. In the mothers, goitre prevalence and thyrotrophin levels decreased significantly, whereas maternal milk and urinary iodine and serum-free thyroxine levels were significantly higher after treatment. The rate of prematurity, stillbirths and abortions in the treated groups was reduced when compared to the untreated group, whereas placental and birth weights were significantly higher. In group D two cases of neonatal hypothyroidism were detected. Their re-evaluation confirmed that hypothyroidism was transient. Groups A, B and C were statistically different from group D with regard to neonatal thyrotrophin and thyroxine. Positive correlations were found between neonatal thyroxine and birth weights and placental weights on the one hand, and maternal urinary iodine and free thyroxine on the other. Consequently, these data indicate that oral administration of lipiodol before or during the first trimester of pregnancy normalizes thyroid function in newborn babies and mothers, increases placental and birth weight and reduces the frequency of iodine deficiency disorders. Lipiodol at this dose and during the first trimester of pregnancy had no deleterious effects and may prevent hypothyroid or neurological cretinism.

Mohamed Lamine Chaouki, Service d'Endocrinologie, Centre Hospitalo-Universitaire de Batna, Route de Tazoult 05000, Batna, Algeria
Cortical bone osteocalcin content and matrix composition in autosomal dominant osteopetrosis type I
Authors: Bollerslev Jens , Marks Sandy C , Mosekilde Lis , Lian Jane B , Stein Gary S , Mosekilde Leif
Published: December 2008

Bollerslev J, Marks SC, Mosekilde L, Lian JB, Stein GS, Mosekilde L. Cortical bone osteocalcin content and matrix composition in autosomal dominant osteopetrosis type I. Eur J Endocrinol 1994;130:592–4. ISSN 0804–4643

Several bone matrix protein constituents, including the major component collagen type I and the hydroxyapatite binding protein, osteocalcin, have been implicated in the regulation of bone turnover. Corticol bone osteocalcin, collagen and mineral content were studied in autosomal dominant osteopetrosis type I (ADO), a disorder characterized by diffuse symmetrical osteosclerosis, Iliac crest bone biopsies were obtained from eight patients (mean age 43.0 years, range 17–63 years) and compared with 16 age- and sex-matched normal controls (mean age 44.1 years, range 20–61 years). The osteocalcin level in cortical bone was increased (p < 0.03) in ADO (51.4 ± 3.9 mg/kg bone) compared with controls (38.0 ± 3.6 mg/kg bone). Total collagen, protein and calcium expressed per kilogram bone dry weight were without significant difference between patients and controls. The pathogenesis of ADO is most likely not related to cortical bone osteocalcin content, a protein implicated in osteoclast ontogeny and activation. These observations are in contrast to recent observations of reduced bone osteocalcin levels in osteopetrotic mutations in the rat and underscore the interspecies heterogeneity of this disorder.

Jens Bollerslev, Dept. of Med. Endocrinology, National Hospital, Pilestredet 32, N-0027 Oslo, Norway
Short-term starvation increases calcidiol-24-hydroxylase activity and mRNA level in rat kidney
Authors: Hagenfeldt-Pernow Ylva , Ohyama Yoshihiko , Sudjana-Sugiaman Elly , Okuda Kyuichiro , Björkhem Ingemar
Published: December 2008

Hagenfeldt-Pernow Y, Ohyama Y, Sudjana-Sugiaman E, Okuda K, Björkhem I. Short-term starvation increases calcidiol-24-hydroxylase activity and mRNA level in rat kidney. Eur J Endocrinol 1994;130:608–11. ISSN 0804–4643

The renal mitochondrial calcidiol-24-hydroxylase activity and the corresponding cytochrome P-450 mRNA level were measured in rats subjected to short-term starvation alone or in combination with calcitriol treatment. Short-term starvation of 24 and 48 h increased the mRNA level by five- and six-fold, respectively. The 24-hydroxylase activity increased by five- and threefold, respectively. Treatment with calcitriol markedly increased the enzyme activity about 20-fold and the mRNA level about six-fold. In rats subjected to calcitriol treatment combined with 24 h of starvation, a significant further increase in enzyme activity was observed. The mRNA levels increased but the difference was not significant statistically. The results indicate that the mechanism by which starvation stimulates the enzymes is different, at least in part, from that behind the stimulatory effect of calcitriol.

Y Hagenfeldt-Pernow, Department of Clinical Chemistry L Huddinge University Hospital, S-141 86 Huddinge, Sweden
Role of the serotoninergic system in the control of gonadotropin secretion in prepubertal male rats
Authors: Pinilla Leonor , Ranchal Antonio , Aguilar Rafaela , Aguilar Enrique
Published: December 2008

Pinilla L, Ranchal A, Aguilar R, Aguilar E. Role of the serotoninergic system in the control of gonadotropin secretion in prepubertal male rats. Eur J Endocrinol 1994;130:617–24. ISSN 0804–4643

To analyze the role of brain serotonin in the control of gonadotropin secretion in prepubertal males, serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations were studied at different ages after administration of 5-hydroxytryptophan (5-HTP), a precursor of serotonin synthesis, alone or in combination with fluoxetine, a specific inhibitor of serotonin uptake; 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), a serotonin 1A agonist; or d.l-p-chlorophenylalanine methyl ester hydrochloride (PCPA), an inhibitor of serotonin synthesis. Also, serum gonadotropin concentrations were measured in castrated males implanted with silastic capsules containing testosterone or 5α-androstane-3α, 17β-diol (α-diol). We found that: (i) the blockade of the serotoninergic system after PCPA administration did not modify basal gonadotropin secretion but did strongly reduce the response to orchidectomy; (ii) a stimulatory effect of 5-HTP on FSH secretion was only observed in intact males at the age of 8 days; (iii) the serotonin 1A agonist 8-OH-DPAT did not change serum gonadotropin concentrations; (iv) 5-HTP increased serum FSH and LH concentrations in 16-day-old castrated males; (v) FSH and LH serum concentrations decreased after 5-HTP in castrated animals implanted with testosterone, whereas castrated animals implanted with α-diol showed, like the intact males, a lack of response to 5-HTP. The main conclusions of our work are: (i) the serotoninergic system does not play a major role in the control of gonadotropin secretion in intact prepubertal male rats; (ii) after removal of the testes (s), and with increased FSH and LH serum concentrations, a clear stimulatory action was observed, suggesting that this stimulatory effect is normally masked when gonadotropin secretion is low; (iii) testosterone and its reduced metabolite α-diol affected differently the role of the serotoninergic system on gonadotropin secretion. After 5-HTP administration, gonadotropin secretion was inhibited in castrated males treated with testosterone, while no changes were observed in castrated males treated with α-diol.

Enrique Aguilar, Department of Physiology, Faculty of Medicine, University of Córdoba, E-14004, Spain
Suicide inactivation of aromatase in human placenta and uterine leiomyoma by 5α-dihydronorethindrone, a metabolite of norethindrone, and its effect on steroid-producing enzymes
Authors: Yamamoto Takara , Tamura Takaya , Kitawaki Jo , Osawa Yoshio , Okada Hiroji
Published: December 2008

Yamamoto T, Tamura T, Kitawaki J, Osawa Y, Okada H. Suicide inactivation of aromatase in human placenta and uterine leiomyoma by 5α-dihydronorethindrone, a metabolite of norethindrone, and its effect on steroid-producing enzymes. Eur J Endocrinol 1994;130:634–40. ISSN 0804–4643

Norethindrone (NET; 17α-ethynyl-19-nortestosterone), a progestogen component of the contraceptive pill, irreversibly inhibits aromatase activity in human placental microsomes. However, it is known also to be aromatized in vitro and in vivo to produce a biologically very active estrogen called ethynylestradiol (EE2). It is therefore inappropriate to administer a high dose of NET to estrogendependent cancer patients for a prolonged time period. In this study, we focused on 5α-dihydronorethindrone (5α-DHNET), a metabolite of NET that is not aromatizable, and the inhibitory effects of 5α-DHNET on human placental and uterine leiomyoma microsomal aromatase and other steroid synthetases. 5α-Dihydronorethindrone showed weak affinity for both estrogen and progestogen receptors. It inhibited significantly human placental aromatase activity in a dose-dependent manner (Ki = 9.0 μmol/l; Kinact = 0.024/min), as well as that of uterine leiomyoma, but did not influence cholesterol side-chain cleavage or 17α-hydroxylase, 21-hydroxylase or 11β-hydroxylase activities. These results suggest that 5α-DHNET may be useful as an aromatase inhibitor, whose use in large doses is expected to reduce the size of estrogen-dependent tumors.

Takara Yamamoto, Department of Obstetrics and Gynecology, Kawaramachi-Hirokoji, Kamikyo-Ku, Kyoto 602, Japan
Long-term treatment of acromegaly with the slow-release somatostatin analogue lanreotide
Authors: Marek Josef , Hána Václav , Kršek Michal , Justová Vlasta , Catus France , Thomas Francois
Published: December 2008

Marek J, Hána V. Kršek M. Justová V, Catus F, Thomas F. Long-term treatment of acromegaly with the slow-release somatostatin analogue lanreotide. Eur J Endocrinol 1994;131:20–6. ISSN 0804–4643

Thirteen patients with active acromegaly despite previous surgery were treated with 30 mg lanreotide im twice a month for 9 months. In 10 subjects the treatment continued to 19 months. GH serum levels of all patients decreased significantly from an initial value of 32.0 (29.4) μg/l [median (standard error of median)] to 10.0 (3.6) and 19.1 (5.7) after 3 and 9 months of treatment, respectively. In the 10 patients with the treatment longer than one year the decrease in GH was from 46.8 (29.4) μg/l to 12.5 (5.0) and 16.1 (5.3) after 13 and 19 months, respectively. IGF-I serum levels decreased significantly from 1193 (73)μg/l to 782 (99) and 621 (103) after 3 and 9 months, respectively, and were normalized in 3 patients. In the 10 patients treated for longer than one year, levels decreased significantly from 1318 (74)μg/l to 653 (170) and 742 (180) after 13 and 19 months, respectively. IGF BP-3 levels were reduced to the normal range in 6 patients and decreased from 8.7 (1.5)mg/l to 6.4 (0.8) and to 5.4 (1.0) after 3 and 9 months, respectively. In the patients with the 19 months treatment the decrease was from 9.3 (1.6) mg/l to 3.9 (0.9) and 4.8 (0.9) after 13 and 19 months, respectively. The IGF BP-3 to IFG I ratio increased in 7 patients. This elevation significantly correlated with the decrease in bioassayable somatomedin. Prolactin serum levels fell in all patients with increased prolactin secretion. Testosterone plasma levels increased in 4 out of 5 men without replacement therapy. Clinical improvement was observed in all patients. A reduction of tumour mass was observed in five patients and complete disappearance of the tumour in one subject. All patients complained of mild abdominal pain and softened stools for several days following the injections. However, these side effects never required interruption of treatment. Asymptomatic microlithiasis was seen in only one patient after 13 months, which led to treatment being suspended for a period of 3 months after which it was resumed. Fasting serum insulin and insulin area under the curve (AUC) after oral glucose tolerance test (OGTT) fell in all patients. Fasting blood glucose, fructosamine and glucose AUC after OGTT slightly increased during the treatment, but all blood glucose levels (fasting and during OGTT) remained within normal ranges. Lanreotide appears to be a safe and effective treatment in patients with active acromegaly unresolved by surgery. The long-acting formulation avoids the drawbacks associated with either repeated daily injections or continuous infusions of somatostatin analogues.

Josef Marek, Third Department of Medicine, Charles University, U nemocnice 1, 128 21 Praha 2, The Czech Republic
Opioid modulation of the gamma-aminobutyric acid-controlled inhibition of exercise-stimulated growth hormone and prolactin secretion in normal men
Authors: Coiro V , Volpi R , Maffei ML , Caiazza A , Caffarri G , Capretti L , Colla R , Chiodera P
Published: December 2008

Coiro V, Volpi R, Maffei ML, Caiazza A, Caffarri G, Capretti L, Colla R, Chiodera P. Opioid modulation of the gamma-aminobutyric acid-controlled inhibition of exercise-stimulated growth hormone and prolactin secretion in normal men. Eur J Endocrinol 1994;131:50–5. ISSN 0804–4643

The possible involvement of endogenous opioids in the gamma-aminobutyric acid-controlled (GABAergic) inhibition of growth hormone (GH) and prolactin (PRL) during physical exercise was evaluated in normal men. After fasting overnight, seven subjects were tested on four mornings at least 1 week apart. Exercise was performed on a bicycle ergometer. The workload was gradually increased at 3-min intervals until exhaustion and lasted about 15 min in all subjects. Tests were carried out under administration of placebo, the opioid antagonist naloxone (10 mg as an iv bolus injection), the GABAergic agonist sodium valproate (600 mg in three divided doses orally) or naloxone plus sodium valproate. During exercise, plasma GH and PRL levels rose 5.5- and 1.9-fold, respectively. The administration of naloxone did not modify, whereas sodium valproate significantly reduced the plasma GH and PRL rise during exercise. In the presence of sodium valproate, GH and PRL levels rose 3- and 1.5-fold, respectively, in response to exercise. When naloxone was given together with sodium valproate, both GH and PRL responses to exercise were abolished completely. These data suggest the involvement of a GABAergic mechanism in the regulation of GH and PRL responses to physical exercise in men. Furthermore, the data argue against a role of naloxone-sensitive endogenous opioids in the control of these hormonal responses to exercise, whereas they suggest a modulation by opioids of the GABAergic inhibitory action.

Vittorio Coiro, Istituto di Clinica Medica Generale e Terapia Medica, Università di Parma, via Gramsci 14, 43100 Parma, Italy
Circadian rhythm of hormones is extinguished during prolonged physical stress, sleep and energy deficiency in young men
Authors: Opstad Per Kristian
Published: December 2008

Opstad PK. Circadian rhythm of hormones is extinguished during prolonged physical stress, sleep and energy deficiency in young men. Eur J Endocrinol 1994:131:56–66. ISSN 0804–4643

The circadian rhythm of hormones (N = 10) and mental performance (N = 18) was investigated in male cadets during a 5-day military training course with continuous heavy physical activities corresponding to 35% of the maximal oxygen uptake, with almost total lack of food and sleep. The 24-h means for androstenedione, dihydroepiandrosterone (DHEA), 17α-hydroxyprogesterone, testosterone and thyroid-stimulating hormone decreased strongly during the course, and the circadian rhythm was extinguished below the minimum levels measured during the control experiment. The 24-h means for cortisol, dihydroepiandrosterone sulfate (DHEA-S) and progesterone increased during the course, and the circadian rhythm was abolished above the maximum levels of the control experiment. A gradual increase was found in thyroxine, free thryoxine and triiodothyronine during the first 12 h of activities, followed by a constant decrease for the rest of the course. Mental performance decreased during the course and the amplitude of its circadian rhythm increased from ±10% to ±30% of the 24-h mean. The circadian rhythms investigated were almost normalized after 4–5 days of rest. However, the nocturnal rise for cortisol, androstenedione and DHEA appeared earlier, and the plasma levels of thyroid hormones, estradiol and DHEA-S were lower during the recovery experiment than in the control experiment. The responses to stress of the circadian rhythm for mental performance and steroid hormones during the course indicate a differential regulation.

Per Kristian Opstad, Norwegian Defence Research Establishment, N-2007 Kjeller, Norway
Simultaneous measurement of plasma 18-oxocortisol and 18-hydroxycortisol levels in normal man
Authors: Yamakita Noriyoshi , Gomez-Sanchez Celso E , Mune Tomoatsu , Morita Hiroyuki , Yoshida Hisashi , Miyazaki Seiji , Yasuda Keigo
Published: December 2008

Yamakita N, Gomez-Sanchez CE, Mune T, Morita H, Yoshida H, Miyazaki S, Yasuda K. Simultaneous measurement of plasma 18-oxocortisol and 18-hydroxycortisol levels in normal man. Eur J Endocrinol 1994;131:74–9. ISSN 0804–4643

Plasma 18-oxocortisol (18-oxoF) and 18-hydroxycortisol (18-OH-F) were measured in 47 healthy subjects. Plasma 18-oxoF and 18-OH-F in the early morning were 0.827 ± 0.04 nmol/l and 3.29 ± 0.175 nmol/l, respectively. The plasma levels of both steroids correlated with each other and with cortisol, but not with aldosterone. Postural stimulation with or without furosemide administration increased 18-oxoF, 18-OH-F, aldosterone and plasma renin activity (PRA). Two hours after 2 mg of oral dexamethasone administration or after an overnight 2 mg of dexamethasone suppression cortisol, 18-oxoF and 18-OH-F decreased. Cortisol, aldosterone, 18-oxo-F and 18-OH-F increased after the intravenous administration of 250 μg of 1–24 ACTH. Changes in plasma 18-oxo-F and 18-OH-F levels correlated with PRA change during the posture studies and correlated with the change of ACTH during the dexamethasone studies. The ratios of post-/pre-test values of the postural stimulation and dexamethasone suppression in 18-oxoF and 18-OH-F were lower than that of aldosterone. Plasma 18-oxoF and 18-OH-F are more dependent on ACTH than on the reninangiotensin system. The ratio of 18-OH-F/18-oxoF, which is between 4 and 5, remains constant during the various stimulation or suppression maneuvers.

Noriyoshi Yamakita, Department of Internal Medicine, Matsunami General Hospital, Kasamatsu, GifuPrefecture, 501-61 Japan