bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of food restriction on 24-h serum and pineal melatonin content in male rats
Authors: Chik C. L. , Ho A. K. , Brown G. M.
Published: December 2008

Abstract. Food restriction (50%) effects on the 24-h rhythm of serum and pineal melatonin (MT) were studied in 260–300 g male Wistar rats under a lighting regimen of 14 h light and 10 h dark. Body weight, testicular weight, accessory organ weights, serum LH, serum testosterone, and 24-h rhythms of serum and pineal MT were determined. One week of food restriction caused a decrease in body weight (18%), accessory organ weights (18%), and serum LH (50%), but had no effect on serum or pineal MT. Three weeks of food restriction suppressed the body weight and accessory organ weights further (35% and 39%, respectively), reduced serum LH (68%) and serum testosterone (53%), reduced pineal MT (12%) and raised serum MT (34%). The increased serum MT may play a role in the reported potentiation of pineal action in food deprived rats.
Defective regulation of glucokinase in rat pancreatic islet cell tumours
Authors: Lenzen Sigurd , Tiedge Markus , Flatt Peter R. , Bailey Clifford J. , Panten Uwe
Published: December 2008

Abstract. The role of glucokinase in the regulation of insulin secretion was examined in normal rat pancreatic islets and in chemically- and radiation-induced rat pancreatic B-cell tumours which show an impaired insulin secretory response to glucose. In normal rats glucokinase activity in cytoplasmic fractions of pancreatic islets was decreased with the duration of fasting and increased by refeeding or insulin administration. This observation is consistent with the induction of glucokinase by insulin. Hexokinase activity was only slightly reduced during fasting. Glucokinase activity decreased in cytoplasmic fractions of streptozotocin-nicotinamideinduced rat pancreatic islet cell tumours. Glucokinase activity contributed about 75% to the total glucose phosphorylation capacity in cytoplasmic fractions of normal pancreatic islets and of small (< 1 mg) streptozotocin-nicotinamide-tumours. This proportion decreased to about 20% in the large streptozotocin-nicotinamide tumours. Glucokinase activity in cytoplasmic fractions of transplantable radiation-induced NEDH (New England Deaconess Hospital) rat B-cell tumours was seven times lower than in normal pancreatic islets and contributed only 15% to the total glucose phosphorylation capacity. In contrast, hexokinase activity of the NEDH tumour B-cells was 2.5 times higher than normal. Decreased glucokinase activity in the chemically- and radiation-induced tumour B-cells appears to result from a loss of the ability of insulin to induce this enzyme and may explain the lack of insulin secretory responsiveness of these tumour B-cells.
Effect of danazol on gonadotropin and cAMP stimulated progesterone synthesis in cultured human granulosa cells
Authors: Olsson Jan-Henrik , Hillensjö Torbjörn
Published: December 2008

Abstract. The effect of danazol on progesterone formation was studied in cultured human granulosa cells obtained from 20 follicles in the mid- to late follicular phase of normally menstruating women. The cells were cultured for 2 to 6 days in the presence of danazol (0.01 to 5 mg/l) alone and in combination with one of several progesterone stimulatory agents. The medium was changed every other day and analysed for progesterone with radioimmunoassay. In all cases progesterone synthesis was markedly stimulated by human FSH (10 μg/l), human LH (10–100 μg/l), hCG (1000 IU/l), forskolin (1 μmol/l) or 8-Bromo-cAMP (1 mmol/l). In the presence of danazol (1 mg/l) the FSH-, LH- and hCG-stimulated progesterone synthesis was partially inhibited by 55 to 60%. The response to forskolin or 8-Bromo-cAMP was also inhibited by danazol although to a somewhat lower extent (35 to 50%). Basal progesterone synthesis was inconsistently inhibited in some cases. It was concluded that not only gonadotropin-stimulated steroid synthesis, as previously demonstrated for hCG, but also forskolin and 8-Bromo-cAMP-stimulated steroidogenesis is sensitive to danazol inhibition. This suggests that the effect of danazol in human granulosa cells is due, at least partly, to interference with steps distal to cAMP generation.
Thyroid stimulating antibody: an index of thyroid stimulation in Graves' disease?
Authors: Baldet L. , Madec A. M. , Papachristou C. , Stefanutti A. , Jaffiol C.
Published: December 2008

Abstract. Early (20 min) thyroid radio-iodine uptake (ERU) and thyroid-stimulating antibodies (TSab) were determined in 27 untreated unselected patients with Graves' disease at the time of diagnosis. In 21 subjects the same tests were further performed in parallel during combined carbimazole-L-T3 therapy (mean duration of follow-up: 10.8 ± 5.8 months; mean ± sd). TSab was determined by a cAMP-human thyrocyte culture stimulation assay and expressed in μl-equivalent of a TSab standard/ml (μl-eq/ml). Before treatment, ERU, ranging from 15 to 54% of the injected dose (normal ≤ 8% dose) correlated with serum T3 (r: 0.54; P < 0.01); TSab, ranging from 6 to 85 μl-eq/ml was detected in 21/27 patients. There was a significant correlation between ERU and TSab (Spearman rank test: r: 0.57; P < 0.01). During the first months of treatment, 5 of the 21 patients sequentially studied had undetectable TSab levels throughout the study and in these patients ERU decreased by 57% of its initial value; the remaining 16 subjects were divided into two groups according to ERU changes: in group A (9 patients), initial ERU decreased by 50% or more or the absolute value became less than 20% of the dose and TSab decreased from 10.9 ± 4.8 ISP-μl-eq/ml to 5.3 ± 1.6 μl-eq/ml (P < 0.01); in group B (7 patients), the fall of ERU was less than 50% or the absolute value remained greater than 20% of the dose and TSab values remained unchanged. Furthermore, the values of ERU and TSab serially obtained during treatment varied in parallel in the 9 patients of group A, whereas in group B, TSab and ERU evolutions were discordant. These two patterns of TSab and ERU changes could not be related to any clinical or biological findings. We conclude that 1) ERU is more closely related to thyroid overstimulation than TSab in untreated patients with Graves' disease, but that there is a significant relationship between ERU and TSab values; 2) during antithyroid therapy, the TSab decrement was significantly greater in patients in whom initial ERU decreased by 50% or more or the absolute value became less than 20% of the dose than in patients with persistent high ERU levels; 3) the follow-up of these patients during antithyroid-L-T3 treatment showed two patterns of changes for ERU and TSab, parallel in some patients, discordant in others, suggesting an heterogeneity in the in vivo TSab effect from one patient to another.
Antibodies to membrane antigens in autoimmune thyroid disease
Authors: Furmaniak J. , Bradbury J. , Smith B. Rees
Published: December 2008

Abstract. The possibility that sera from patients with autoimmune thyroid diseases contain autoantibodies to thyroid membrane proteins distinct from microsomal antigen and the TSH receptor has been investigated using (a) solid phase assay system based on human thyroid membranes and 125I-labelled protein A and (b) immunoprecipitation of detergent solubilized 125I-labelled thyroid membranes followed by gel electrophoresis and autoradiography. In the solid phase assay binding to membranes showed a highly significant correlation with binding to microsomes (r = 0.82; P < 0.001; N = 82) indicating that the interaction between the serum and the membranes was due principally to microsomal antibody binding to microsomal antigen contaminating the membrane preparations. However, there were some discrepancies suggesting that an additional antigen-antibody system was involved. This possibility was then investigated using immunoprecipitation of 125I-labelled thyroid membranes. A labelled protein with mol wt 54 K was specifically immunoprecipitated (relative to normal pool serum) by 3 out of 4 sera from patients with Graves' disease who showed high binding to thyroid membranes. A further 4 sera from such patients with low membrane binding affinity failed to immunoprecipitate the 54 K protein. Sera from some patients with Hashimoto's disease and some patients with rheumatoid arthritis and one patient with Addison's disease also immunoprecipitated the 54 K protein from solubilized thyroid membranes. These studies suggested that antibodies interacting with the 54 K protein contributed to the discrepancies between thyroid membrane and microsome binding. However, the 54 K protein was also immunoprecipitated from detergent solubilized membranes prepared from human placenta, skeletal muscle and adrenal tissue. Immunoprecipitation studies with antisera to cytoskeleton proteins suggested that the 54 K band was the intermediate filament protein desmin. Consequently, thyroid specific antibody-antigen systems distinct from those involving microsomal antibody (or thyroglobulin antibody) could not be detected in thyroid membranes by immunoprecipitation.
Plasma growth hormone in acromegalic patients
Authors: Christensen Stig Engkjær , Weeke Jørgen , Ørskov Hans , Jøgensen Jens Otto Lunde , Esmann Jørgen , Doxey John C.
Published: December 2008

Abstract. The effects of the selective α2-adrenoreceptor antagonist idazoxan on diurnal variations in plasma growth hormone levels were studied in acromegalic patients. Seven patients entered the study; six patients had been unsuccessfully treated with either pituitary adenotomy, bromocriptine or other drug therapy or a combination of the two procedures. Plasma growth hormone levels were measured at hourly intervals over a period of 24 h under control conditions and following 4 days treatment with either placebo or idazoxan (20 mg po, three times a day); the comparison of idazoxan with placebo was a double blind cross-over study. Except in one patient, the diurnal growth hormone plasma profiles were virtually superimposable under control conditions and following either placebo or idazoxan; each patient had a characteristic profile. Four patients had impressive nocturnal elevations ranging from about 40 to 200 per cent above average daytime levels. Only one had definite paradoxical early postprandial peaks. These observations are contrary to accepted views on growth hormone levels in acromegalic patients. The majority of our patients thus had profiles reminiscent of the normal diurnal plasma growth hormone pattern albeit at a higher level indicating some preserved central drive. The rather high prevalence in the present study of patients having relapses after adenomectomy may indicate that a selection had been made of cases with hypothalamic aetiology. Administration of the selective α2-adrenoreceptor antagonist idazoxan did not modify plasma growth hormone profiles in these patients.
Dexamethasone fails to suppress hyperendorphinaemia of obese children
Authors: Facchinetti F. , Livieri C. , Petraglia F. , Cortona L. , Severi F. , Genazzani A. R.
Published: December 2008

Abstract. In order to evaluate the origin of hyperendorphinaemia in obese patients, plasma B-endorphin (B-EP), B-lipotropin (B-LPH) and cortisol levels were measured in basal conditions and after overnight treatment with 1 mg of dexamethasone. Thirteen obese children (weight excess ranging from 44 to 100%) and 10 normal weight controls were studied. Weight gain started in prepuberty and could not be explained by concurrent diseases. Hormone levels were measured by RIA, either directly in the plasma (cortisol) or after silicic acid extraction and Sephadex G-75 column chromatography (B-EP and B-LPH). Basal B-EP levels in the obese children (19.4 ± 4.9 pmol/l, mean ± sem) were significantly higher than in the controls (7.8 ± 1.2, P < 0.01), whereas B-LPH and cortisol was within normal range. In the controls, post-dexamethasone morning and afternoon hormone levels were significantly suppressed. In the obese children, B-EP concentrations remained unaffected by the treatment (14.6 ± 5.3 and 14.9 ± 5.2 at 08.00 and 16.00 h, respectively), whereas both B-LPH and cortisol values were significantly decreased. These data demonstrate that a short-term dexamethasone treatment is unable to correct the increased B-EP levels which characterize obese children, whereas it is effective on B-LPH and cortisol concentrations. It can be concluded that circulating B-EP in this condition loses the control of CRH. However, the origin of hyperendorphinaemia in obese patients still remains to be investigated.
The influence of free fatty acids on the free fraction of thyroid hormones in serum as estimated by ultrafiltration
Authors: Bregengåard C. , Kirkegaard C. , Faber J. , Poulsen S. , Siersbæk-Nielsen K. , Friis T.
Published: December 2008

Abstract. Thyroid hormones are displaced from their binding proteins in serum during nonthyroidal somatic illness, and FFA have been claimed to contribute. It seems mandatory to evaluate this effect using techniques for the measurements of serum free thyroid hormones in which serum remains undiluted. We measured the effect of 7 common human FFA on the free fraction of T4, T3 and rT3 in serum from healthy subjects using an ultrafiltration technique by which serum is diluted only minimally. In addition we measured the effect of oleic acid on the free fractions of the iodothyronines in pooled serum from healthy subjects and in pooled serum from patients with nonthyroidal illness. All FFA tested were able to displace both T4, T3 and rT3, but to a varying degree, arachidonic and linoleic acid being the most potent ones. A 20% increase in the free fractions of T4, T3 and rT3, respectively, was obtained by adding between 1.7–3.3 mmol/l, 1.3–4.6 mmol/l and 1.0–2.4 mmol/l of the different FFA. A serum pool obtained from patients with nonthyroidal somatic illness was more sensitive to oleic acid than a serum pool obtained from healthy subjects, since 2–3 times less oleic acid was necessary to induce a 20% increase in the free fractions of thyroid hormones. It is concluded that FFA are able to displace both T4, T3 and rT3 from their serum binding proteins in healthy subjects as well as in patients with nonthyroidal illness. However, serum from patients with nonthyroidal illness was more sensitive to the displacing activity of oleic acid than serum from healthy subjects. This was possibly due to reduced affinity of the serum binding proteins to thyroid hormones, and it could be argued that a factor different from FFA seemed responsible.
Dichotomic action of glucocorticoids on growth hormone secretion
Authors: Nakagawa Koji , Ishizuka Tatsuya , Obara Takao , Matsubara Miyao , Akikawa Kazumasa
Published: December 2008

Abstract. The mechanism of apparently discrepant actions of glucocorticoids (GC) on GH secretion, in vivo suppression and in vitro potentiation, was studied in rats. Dexamethasone (Dex), at the concentration of 50 nmol/l, Potentiated basal and GHRH-stimulated GH release from monolayer culture of normal rat pituitary cells in 48 h. On the other hand, in vivo administration of Dex, 165 μg daily for 3 days, consistently suppressed serum GH levels in female rats. In these rats, the hypothalamic content of immunoreactive (IR) SRIH was significantly increased, whereas that of IR-GHRH was significantly decreased in comparison with the untreated rats. Bioassayable GH-releasing activity was also lower in Dex-treated rats. These findings indicate that the suppressing effect of GC on GH release in vivo is, at least partially, due to the increase in hypothalamic SRIH release and probably also to the decrease in GHRH release, and these effects surpass the potentiating effect of GC on GH release at the pituitary level, resulting in a net inhibitory effect in vivo.
Screening for non-classic 21-hydroxylase deficiency in an HLA-B14 positive population
Authors: Motta P. , Airaghi L. , Catania A. , Mangone I. , Orsatti A. , Tenconi L. , Cantalamessa L. , Zanussi C.
Published: December 2008

Abstract. To evaluate whether HLA-B14 positive individuals are at increased risk for non-classic 21-hydroxylase deficiency, the response of progesterone and 17-hydroxyprogesterone to ACTH stimulation test was studied in a group of 27 apparently normal, HLA-B14 positive, blood donors. Four of these subjects showed a response typical of 21-hydroxylase defect. In the present series, the enzymatic defect was found to have a considerably lower prevalence than in a previous study of smaller size (15% vs 66%); however, considering the low frequency of the gene coding for the defect in the general population (0.015–0.057), the present results confirm an increased risk for non-classic 21-hydroxylase deficiency in HLA-B14 positive individuals. Therefore, in these subjects, a screening for 21-hydroxylase deficiency may be indicated.
The role of opiate, dopaminergic, and adrenergic systems in the hypothalamo-pituitary dysfunction in obesity
Authors: Baranowska B. , Singh S. P. , Soszynski P. , Nowakowski J. , Jeske W.
Published: December 2008

Abstract. In order to evaluate the role of opiate, dopaminergic and adrenergic systems in the mechanism of hypothalamo-pituitary disturbances in obesity, 9 obese women and 14 healthy women were investigated. Serum GH, LH, β-endorphin and cortisol concentrations were measured after administration of clonidine, an α2-adrenergic receptor agonist, and naloxone, an opiate antagonist. Additionally, PRL levels were measured after administration of the dopamine receptor blocker metoclopramide. An impaired GH response to clonidine and naloxone was found in obese women. However, a marked increase in β-endorphin was observed in obese patients after clonidine administration. Naloxone did not cause any significant change in β-endorphin release. Neither clonidine nor naloxone induced any change in LH release. Serum PRL concentrations in response to metoclopramide were significantly higher in obese patients than in healthy women. In conclusion: Disturbed activity in opiate, adrenergic, and dopaminergic systems may be of pathogenetic importance in a hypothalamo-pituitary dysfunction in obesity. The occurrence of hypothalamic amenorrhoea as well as the presence of abnormalities of the central nervous system regulation of GH, PRL, ACTH, cortisol, insulin and vasopressin output might point to a generalized hypothalamo-pituitary dysfunction in obesity.
Pre-operative evaluation of the prognosis of hypertension in primary aldosteronism owing to adenoma
Authors: Saruta Takao , Suzuki Hiromichi , Takita Takashi , Saito Ikuo , Murai Masaru , Tazaki Hiroshi
Published: December 2008

Abstract. The prognosis of hypertension was evaluated pre-operatively in 40 patients with primary aldosteronism owing to adenoma by examining the severity of hypertension, family history of hypertension, age of the patients, duration of hypertension, plasma renin activity, plasma aldosterone concentration, and efficacy of spironolactone (100 mg per day for 10 days) on blood pressure. In 30 of the 40 patients, the blood pressure was reduced to below 160/95 mmHg within a year after adrenalectomy (responders). In the other 10 patients, the blood pressure was not markedly reduced and remained above 160/95 mmHg (nonresponders). There were no significant differences in the age of the patients, family history of hypertension, plasma renin activity or plasma aldosterone concentration between these two groups. The severity of hypertension as judged by the WHO classification and the duration of hypertension prior to operation seemed to be of some use in assessing the postoperative prognosis of hypertension, but the efficacy of spironolactone was far more useful. That is to say, a reduction in mean blood pressure of more than 15 mmHg after administration of spironolactone was observed in 29 of the 30 responders. The remaining one patient showed an 11 mmHg reduction in mean blood pressure. On the other hand, none of the nonresponders revealed a reduction in mean blood pressure of more than 15 mmHg after spironolactone administration. From these results it is concluded that the pre-operative response of blood pressure to administration of 100 mg per day of spironolactone for 10 days represents a useful indicator of the postoperative prognosis of hypertension in patients with primary aldosteronism owing to adenoma.
Growth hormone, somatomedin levels and growth regulation in Turner's syndrome
Authors: Ranke Michael B. , Blum Werner F. , Haug Frank , Rosendahl Werner , Attanasio Andrea , Enders Herbert , Gupta Derek , Bierich Jürgen R.
Published: December 2008

Abstract. In a total of 56 children and adolescents with Turner's syndrome (41 with karyotype 45,X) basal serum levels of somatomedin bioactivity, Sm-C/IGF-I (RIA), IGF II (RIA), GH response to arginine and GHRH (GRF(1-29)NH2), and spontaneous GH secretion during 5.5 h of deep sleep were determined in a cross-sectional manner. GH responses to GRF and arginine as well as IGF-II levels were found to be in the normal range. Levels of somatomedin bioactivity were higher than normal before a bone age of 10 years, in the low-normal range thereafter, and below normal in some patients. Levels of Sm-C/IGF-I were found normal before and low-normal after a bone age of ten years. There was a trend towards increasing Sm-C/IGF-I levels with age. In contrast to the normal pattern, spontaneous sleep-related GH secretion was declining with age and did not show the puberty-associated rise. These findings suggest a normally functioning growth hormone-somatomedin axis in Turner's syndrome with alterations of its functioning level occurring secondarily as a result of absent gonadal activation. In single patients abnormally low growth hormone and/or somatomedin secretion may be present.
The postpartum period constitutes an important risk for the development of clinical Graves' disease in young women
Authors: Jansson Rolf , Dahlberg Per Anders , Winsa Brita , Meirik Olav , Säfwenberg Jan , Karlsson Anders
Published: December 2008

Abstract. In the present study, 93 consecutive women, 20–40 years of age, referred to our clinic from 1976–85 with Graves' disease, were examined with respect to a possible relation between onset of disease and previous pregnancy. An increased relative risk of 6.5 (3.8–11.0, 95% confidence interval) of developing Graves' disease within one year following delivery was found. After excluding the nulliparous women, almost 2 out of 3 women who developed Graves' disease in the principal child-bearing age of 20–35 years had a postpartum onset, suggesting an important role of immunomodulatory events following delivery for the development of this disease in young women. Future studies will ascertain to which extent the recognition of postpartum Graves' disease has implications on the choice of therapy in this group of women.
Cytostatics for acromegaly
Authors: Kasperlik-Zaluska A. A. , Wislawski J. , Kaniewska J. , Zborzil J. , Frankiewicz E. , Zgliczyński S.
Published: December 2008

Abstract. A 21-year-old woman suffering from acromegaly was treated with transsphenoidal subtotal hypophysectomy (microscopy: acidophilic adenoma), followed by x-ray and bromocriptine therapy. Seven years later she was re-operated because of a partial bitemporal loss of vision, intracranial hypertension, and regrowth of the pituitary tumour seen on CT-scan. A large part of the invasive suprasellar tumour was then removed by transcranial approach. The neurosurgery was followed by cobalt radiotherapy and bromocriptine administration. Two years later, symptoms and signs of tumour growth reappeared. Administration of cytostatics, such as doxorubicin (Adriamycin®) and lomustine (Belustine®), resulted in distinct clinical improvement associated with a seven-fold decrease in the serum growth hormone concentration. The visual field became normal and the intracranial mass on a CT scan decreased markedly. As a result the patient was able to resume work.
Morphological study of the effects of an GnRH agonist on the canine testis after 4 months of treatment and recovery
Authors: Dubé D. , Assaf A. , Pelletier G. , Labrie F.
Published: December 2008

Abstract. After 4 months of treatment of adult male dogs with the GnRH agonist (GnRH-A) [D-Trp6]GnRH ethylamide, the seminiferous tubules contained only type A and B spermatogonia, Sertoli cells, and rare primary spermatocytes, thus causing a 64% decrease in testis weight. At the electron microscope level, Sertoli cells showed an increase in phagosomes and lipid droplets. Leydig cells were markedly atrophied with the accumulation of lipid droplets and showed a pre-dominance of mitochondria with lamellar instead of vesicular cristae. Four months after cessation of treatment with GnRH-A, a complete return to normal spermatogenesis and Leydig cell morphology was observed. The full reversibility of spermatogenesis in the dog after chronic GnRH-A treatment suggests that this well-tolerated peptide could be used as a reversible method of male contraception.
Free thyroxine, free triiodothyronine, and thyrotropin concentrations in hypothyroid and thyroid carcinoma patients receiving thyroxine therapy
Authors: Liewendahl K. , Helenius T. , Lamberg B.-A. , Mähönen H. , Wägar G.
Published: December 2008

Abstract. Free thyroxine (FT4) and free triiodothyronine (FT3) concentrations in serum were measured by direct equilibrium dialysis methods in patients receiving thyroxine replacement or suppression therapy. Four of 50 hypothyroid patients euthyroid on replacement therapy (mean thyroxine dose 120 μg/day) had supra-normal FT4 concentrations, whereas the FT3 concentrations were normal in all. Forty-one of 56 operated thyroid carcinoma patients on suppressive therapy (mean thyroxine dose 214 μg/day) had raised FT4 concentrations, whereas the FT3 concentration was elevated in only one patient. There was a large difference in mean FT4 values for hypothyroid and thyroid carcinoma patients (17.2 vs 29.5 pmol/l), whereas the difference in mean FT3 values was small (5.0 vs 6.1 pmol/l), suggesting a decreased peripheral conversion of T4 to T3 with increasing concentrations of FT4. Serum TSH concentrations, as determined by an immunoradiometric assay, varied from < 0.02 to 11.9 mU/l in treated hypothyroid patients; 21 patients (42%) had values outside the reference limits. As a single test, serum TSH is therefore not very useful for the assessment of adequate thyroxine dosage in patients with primary hypothyroidism. In thyroid carcinoma patients, the TSH concentrations were < 0.18 mU/l; 45 patients had values < 0.02 mU/l indicating sufficient suppression of TSH secretion in the majority of cases. On the basis of these results we recommend the combination of FT3 and TSH tests for monitoring thyroxine replacement and suppression therapy. FT4 appears less useful than FT3 for this purpose even if special reference values values were adopted for each patient group.
Interaction of ovine somatomedin and multiplication stimulating activity/rat insulin-like growth factor II with cultured skeletal muscle satellite cells
Authors: Dodson Michael V. , Allen Ronald E. , Shimizu Nobuyoshi , Shimizu Yoshiko , Hossner Kim L.
Published: December 2008

Abstract. The interactions of 125I-multiplication stimulating activity (MSA) and 125I-ovine somatomedin with receptors on skeletal muscle satellite cells are described. Specific binding of 125I-MSA/rIGF-II was inhibited by MSA/rIGF-II and oSm but not by insulin. Binding of 125I-oSm was inhibited by MSA/rIGF-II, oSm and insulin. In addition, 24-h pre-incubation of satellite cells with insulin increased the amount of 125I-MSA/rIGF-II bound, but insulin concentrations below 550 μg/l had no effect on the subsequent binding of 125I-oSm. Pre-incubation of cultures with oSm or MSA/rIGF-II decreased the subsequent binding of 125I-oSm and 125I-MSA/rIGF-II. These preliminary experiments suggest that oSm is similar to IGF-I in its binding characteristics and that primary cultures of skeletal muscle satellite cells possess type I and type II IGF receptors.
Hyperthyroidism due to a thyroid-stimulating hormone (TSH)-secreting pituitary adenoma associated with functional hyperprolactinaemia
Authors: Savastano S. , Lombardi G. , Merola B. , Miletto P. , Di Prisco B. , Manco A. , Beck-Peccoz P. , Faglia G.
Published: December 2008

Abstract. This paper reports the case of a 31-year-old woman with hyperthyroidism, increased TSH and thyroid hormone levels, evidence of a pituitary adenoma, hyperprolactinaemia, amenorrhoea, and galactorrhoea. Following trans-sphenoidal pituitary adenomectomy, mild hyperthyroidism and increased TSH and α subunit levels persisted, whereas hyperprolactinaemia, amenorrhoea, and galactorrhoea disappeared. Serum TSH levels were not affected by administration of TRH, metochlopramide, domperidone, 1-dopa or somatostatin. Serum TSH chromatography showed a normal pattern. Following a second trans-spenoidal pituitary adenomectomy and radiotherapy, hyperthyroidism disappeared, and the TSH and α subunit levels returned to normal. Light microscopy showed no specific TSH immunostaining although electron microscopy revealed numerous secretory granules alined along the plasma membrane. The post-operative follow-up confirmed the presence of a TSH-secreting pituitary adenoma associated to functional hyperprolactinaemia.
Effect of 1,25-dihydroxyvitamin D3 on rat pituitary prolactin release
Authors: Törnquist Kid
Published: December 2008

Abstract. The effect of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on PRL secretion from rat pituitary in vivo and in vitro was investigated. Treating the rats for three days with 0.05 μg/kg per day had no effect on basal PRL secretion, whereas the TRH-induced PRL secretion was increased (P < 0.001). The enhancing effect of 1,25(OH)2D3 was blunted by verapamil. Incubating dispersed anterior pituitary cells with 10−8 mol/l 1,25(OH)2D3 induced a significant increase in PRL secretion after 96 h (364 ± 30 ng/well vs 481 ± 33 ng/well, P < 0.001; mean ± sem) compared with control cells. The TRH-induced PRL secretion was increased in cells incubated with 1,25(OH)2D3 for 144 h (0.766 ± 0.061 vs 1.024 ± 0.076 μg/well, P < 0.05; mean ± sem) compared with control cells. Neither 25-hydroxyvitamin D3 (25OH-D3) nor 24,25-dihydroxyvitamin D3 had any effects on the PRL secretion. However, when the cells were incubated with both 10−8 mol/l 1,25(OH)2D3 and 10−6 mol/l 25OHD3, the enhancing effect of 1,25(OH)2D3 on the basal PRL secretion was blunted. The results suggest that 1,25(OH)2D3 possibly affects the regulation of PRL release from the rat pituitary and that this effect is specific for 1,25(OH)2D3.
Treatment of Graves' ophthalmopathy with high-dose intravenous methylprednisolone pulse therapy
Authors: Nagayama Yuji , Izumi Motomori , Kiriyama Takeshi , Yokoyama Naokata , Morita Shigeki , Kakezono Fumiko , Ohtakara Shigeru , Morimoto Isao , Okamoto Sumiaki , Nagataki Shigenobu
Published: December 2008

Abstract. This preliminary study was undertaken to investigate the efficacy of high-dose iv methylprednisolone pulse therapy in 5 patients with Graves' ophthalmopathy. One gram of methylprednisolone sodium succinate was given iv daily for 3 successive days. The 3-day infusion was repeated 3 to 7 times at intervals of 1 week; total duration of pulse therapy was 3 to 7 weeks. The clinical improvement of eye involvements by pulse therapy was assessed immediately after the last pulse therapy. The clinical assessment of the effect of pulse therapy for Graves' ophthalmopathy showed a good response in 3 patients, a fair response in one, and no response in one. However, in one patient, who was judged to show no response, complete improvement of the enlarged extraocular muscle was observed on orbital computed tomography. Moreover, two patients, who have been followed without any other therapies, showed no relapse of eye involvements for 32 and 10 months, respectively. Although it is impossible to determine whether pulse therapy is more effective than other immunosuppressive therapies, the results of this preliminary study suggest that pulse therapy may be a good immunosuppressive therapy for Graves' ophthalmopathy too. Controlled studies are desired.
Evaluation and significance of the degree of pituitary-gonadal inhibition during intranasal administration of buserelin
Authors: Bourguignon J. P. , Heinrichs C. , Van Vliet G. , Vandeweghe M. , Vanderschueren-Lodeweyckx M. , Malvaux P. , Du Gaju M. , Craen M. , Lambrechts L. , Delire M. , Ernould C.
Published: December 2008

Abstract. In 12 patients (11 girls, 1 boy) with central precocious puberty and 4 patients (3 girls, 1 boy) with idiopathic short stature treated for 1 year with a GnRH superagonist, buserelin (0.3 mg intranasally, 4 times a day), a variable degree of inhibition of sex steroid secretion and pubertal development was observed. Regression of breast or genital development required a daily dosage of buserelin ≥ 34 μg/kg. After 3, 6, 9 and 12 months of treatment, the serum oestradiol level in the girls was positively related (r = 0.69) to basal serum LH measured at the same time and to change in breast development during the previous 3 months. In contrast, LH response to GnRH was very low in all the patients and not related to the degree of oestradiol inhibition. Height velocity and bone age velocity during the year of treatment showed no significant correlation with mean oestradiol level. Bone age velocity during treatment was inversely related to bone age at onset of buserelin. These data show that 1) the pituitary gonadal suppression during intranasal administration of buserelin is variable and dose-dependent; 2) gonadotropin response to GnRH is not a sensitive indicator of incomplete pituitary suppression during buserelin treatment; and 3) bone age velocity during treatment is more reduced the more advanced bone age is at onset of treatment.
Changes during lactation in the renin-like enzyme concentration in rat luteal tissue
Authors: De Vito Eduardo , Cabrera Ricardo R. , Guardia D. Cecilia
Published: December 2008

Abstract. The activity of a renin-like enzyme (RLE) previously found in rat copora lutea was studied during lactation. Luteal RLE concentration significantly increased after delivery and reached a maximum on day 5 of lactation. Plasmatic levels of PRL and progesterone also increased through lactation. Treatment with 2 bromo-alpha-ergocryptine, which diminished plasma PRL and progesterone levels, enhanced luteal RLE activity. Therefore, the increase in luteal RLE during lactation seems to be independent of PRL and progesterone levels, but dopamine could be involved in its regulation. The increase in luteal RLE is not related to the intensity of the suckling stimulus, since RLE values were not modified in mothers suckling 2 to 10 pups. In conclusion, RLE activity in rat corpora lutea changes during lactation with a pattern similar to that of plasmatic PRL and progesterone, but seems not to be regulated by these hormones, nor by the intensity of suckling. On the contrary, luteal RLE may be regulated by dopamine.
Nicotinic and M1-, M2-muscarinic cholinergic control of ACTH response to insulin-induced hypoglycaemia in man
Authors: Coiro V. , Passeri M. , Gelmini G. , Davoli C. , Bianconcini G. , Volpi R. , Minelli R. , Delia P. , Fagnoni F. , Chiodera P.
Published: December 2008

Abstract. The possible mediation of muscarinic and/or nicotinic-cholinergic receptors in the response of ACTH to insulin-induced hypoglycaemia was evaluated in 18 normal men. Subjects were tested with the insulin (0.15 U/kg) tolerance test (ITT) in basal conditions and in the presence of the M1- and M2-muscarinic antagonist atropine (600 μg iv just before insulin injection (time 0) plus 600 μg 20 min later in 6 subjects) or the M1-muscarinic receptor blocker pirenzepine (40 mg iv 10 min before ITT or 20 mg at time 0 plus 30 mg at time 20 in 6 subjects). The remaining 6 men were treated with the nicotinic receptor antagonist trimethaphan (0.3 mg/min × 30 min before ITT). ACTH rose 4.7 times in response to hypoglycaemia. The ACTH response to hypoglycaemia did not change after pirenzepine administration, whereas it was significantly increased by atropine and decreased by trimethaphan treatment. These data indicate that nicotinic and muscarinic (M2 but not M1) receptors participate in a different manner in the regulation of the hypoglycaemia-induced ACTH release.
Sequential effects of FSH on the first stages of ovarian follicular development in normal and dwarf Snell mice
Authors: de Reviers M. M.
Published: December 2008

Abstract. The population of small growing ovarian follicles was divided into 4 classes according to the number of granulosa cells (from 15 to 95) surrounding the oocyte, and a comparison was made of normal and dwarf mice. Follicular cell proliferation was estimated by tritiated thymidine incorporation. In normal mice, most follicles in classes 1 (15 to 35 granulosa cells in their largest cross-section) and 2 (36 to 55 cells) were labelled (86 and 95%, respectively); FSH treatment increased the labelling index (L.I.) in all follicle classes. In dwarf mice, only 38 and 76% of follicles in classes 1 and 2, respectively, were labelled. However, FSH treatment increased the percentage of labelled follicles and the L.I. to levels which were similar to those in the ovaries of untreated, normal animals. FSH stimulation of the percentage of labelled follicles and L.I. was obvious as early as 3 h after injection. There was a major increase of the L.I. 24 h after FSH stimulation, specially in dwarf mice; several hypotheses are proposed to explain this finding. We conclude that FSH is necessary for the development of the population of small growing follicles in the mouse ovary.
Alterations in thyroidal economy in a systemic illness induced by turpentine oil injection to the rat
Authors: Huang Tien-Shang , Chopra Inder J. , Boado Ruben , Wu Tzu-Chin , Tashkin Donald P. , Solomon David H. , Teco Guadalupe N. Chua
Published: December 2008

Abstract. Injection of turpentine oil (5 μl/g, sc) to Sprague Dawley rats was associated with a significant reduction in serum concentration of T4, T3 and TSH that lasted throughout 48 h of study. Dialyzable fraction of T4 and resin uptake of T3 did not change for 10 h after turpentine oil injection, but were increased significantly at 24 h and 48 h. Serum rT3 concentration was decreased significantly at 24 h and 48 h. The pituitary content of TSH in the experimental rat was significantly increased at 24 h after turpentine oil injection, but the TSH-β subunit content was decreased significantly. Serum TSH response to TRH did not change in experimental rats. Thyroidal radioiodine uptake, serum T4, and serum T3 in experimental rats demonstrated little or no increase in response to exogenous bovine TSH. A thyroid hormone binding inhibitor (THBI) was detected in serum and iodothyronine 5'-monodeiodinating activity was decreased significantly in liver, kidney and heart of rats injected repeatedly with turpentine oil. Oxygen consumption of experimental rats did not change appreciably. Our data suggest that administration of turpentine oil to the rat leads, within a few hours of the injection, to a systemic illness associated with marked changes in thyroidal economy.
No effect of superoxide dismutase on spontaneous development of diabetes in db/db mice
Authors: Berglund Ove , Grankvist Kjell , Albiin Carina , Marklund Stefan L.
Published: December 2008

Abstract. B-cells have previously been shown to be very susceptible to damage induced by superoxide radicals, and protection against such damage has been achieved both in vitro and in vivo with superoxide dismutase. During maturation, db/db mice develop diabetes and accumulation of potentially superoxide radical-producing leucocytes can be demonstrated in the islets during the process. To test for the possibility that superoxide radical-induced damage contributes to the development of diabetes, db/db mice were given daily ip injections of 200 mg/kg polyethylene glycolsubstituted CuZn superoxide dismutase. No effect of the treatment could be demonstrated.
Effects of osmotically stimulated endogenous vasopressin on basal and CRH-stimulated ACTH release in man
Authors: Bähr V. , Hensen J. , Hader O. , Oelkers W.
Published: December 2008

Abstract. Two groups of six healthy young males participated in separate experiments to examine the physiological role of endogenous vasopressin in h-CRH-induced (100 μg iv) ACTH release: a) after drinking of 3500 ml of water; b) after thirsting for 23 h; c) after 0.9% saline infusion, and d) after 5.0% saline infusion (0.06 ml/kg per min for 120 min). AVP levels were markedly elevated (4 ng/l) after thirsting and 5% saline infusion when compared with water loading or infusion of physiological saline. Although basal and h-CRH-stimulated ACTH and cortisol levels tended to be higher during hypertonic saline infusion and dehydration, no significant difference was observed between states of high or low endogenous AVP levels. These results are not in accordance with previous studies using ovine CRH, which might be due to its longer half-time or the timing of the changes in AVP plasma levels in relation to the CRH injection. Our data suggest that the osmotic modulation performed in this study results in AVP concentrations in the adenohypophysis, which are in the threshold range for influencing ACTH release induced by exogenous h-CRH.
The influence of oleic acid on cAMP accumulation of thyroid plasma membrane activated by thyrotropin
Authors: Chang Tien-Chun , Huang Tien-Shang
Published: December 2008

Abstract. Several thyroid hormone binding inhibitors have been described in nonthyroid illness. One of the major inhibitors, oleic acid, is present in excess amounts in sera of patients with nonthyroid illness. In this study, we demonstrated that oleic acid inhibited the cAMP accumulation of thyroid plasma membrane activated by thyrotropin at 50 μmol/l and higher concentrations. In the presence of albumin, oleic acid significantly inhibited the cAMP accumulation of plasma membrane activated by thyrotropin at 2.4 mmol/l (P < 0.01 when the albumin concentration was 40 g/l and pH was 7.4; P < 0.001 when the albumin concentration was 20 g/l and pH was 7.2). These findings suggest that in nonthyroid illness, especially at a low albumin concentration and low blood pH, a high oleic acid concentration may influence the thyroid function directly in addition to inhibiting the thyroid hormone binding to serum protein. Oleic acid also could inhibit 5′-guanylylimidodiphosphate- and forskolin-induced cAMP production in thyroid plasma membranes. Therefore, the inhibiting effect of oleic acid may be through the action of oleic acid on the catalytic unit of the hormone-sensitive adenylate cyclase system.
Transsphenoidal microsurgery as primary treatment in 25 acromegalic patients: results and follow-up
Authors: van 't Verlaat Johanna W. , Nortier Johan W. R. , Hendriks Martin J. , Bosma Nicolaas J. , Graamans Kees , Lubsen Herman , Vasen Hans F. A. , Thijssen Joseph H. H. , Croughs Ronald J. M.
Published: December 2008

Abstract. Twenty-five patients with acromegaly were treated by transsphenoidal microsurgery. Fourteen patients (56%) were considered cured according to the following criteria: a. basal plasma GH < 10 mU/l; b. glucose suppressed plasma GH≤4 mU/l, and c. disappearance of TRH responsiveness if present preoperatively. Thirteen of the cured patients were reevaluated after a mean follow-up period of 3.5 years (range 1.5 to 5.5 years). At that time, basal plasma GH was still < 10 mU/l and glucose suppressed plasma GH was still ≤ 4 mU/l in all patients, indicating the practical value of our criteria. The remaining 11 patients (44%) received additional treatment by external pituitary irradiation and bromocriptine. Owing to surgery, 5 patients (20%) developed partial or panhypopituitarism.
Preventive action of phentolamine on adrenaline induced blood glucose elevation in humans
Authors: Porta S. , Hofmann H. M. H. , Ertl U. , Rinner I. , Puerstner P. , Weiss P. A. M. , Felsner P. , Korsatko W.
Published: December 2008

Abstract. A comparison of the action of adrenaline infusion and a combined adrenaline + alpha blocker (phentolamine, Regitine®) infusion on blood glucose (BG), plasma immunoreactive insulin (IRI), BG/IRI ratio, C-peptide, and plasma cortisol levels was made in healthy young human subjects. The purpose of the experiment was to check, whether alpha block could abolish adrenaline-induced enhancement of blood glucose levels. The results show that during enhanced adrenaline levels, the use of regitine could indeed normalize blood glucose levels, not so much by increasing the IRI secretion, but by diminishing adrenalineinduced liver glycogenolysis via alpha receptors. This could be a model to prevent stress (adrenaline) induced metabolic deviations in diabetics, especially before and during predictable stress situations, e.g. examinations or surgery.
Effects of neuromedin B, gastrin-releasing peptide-10 and their fragment peptides on secretion of gastrointestinal and pancreatic hormones in dogs
Authors: Kawai Koichi , Chiba Yukinobu , Mukai Hidehito , Munekata Eisuke , Yamashita Kamejiro
Published: December 2008

Abstract. The effects of neuromedin B (NMB), gastrin-releasing peptide (GRP)-10 and their C-terminal fragment peptides on the pancreatic and gastrointestinal hormone release were studied in dogs. Intravenous bolus injections of NMB and GRP-10 (4.5 nmol/kg) into conscious dogs elicited a sharp and statistically significant rise in plasma gastrin and insulin levels, but only GRP-10 brought on a significant rise in the plasma glucagon and enteroglucagon levels. The degree of stimulation of gastrin and insulin secretion by NMB and GRP-10 was dose-dependent. With a dose of 4.5 nmol/kg, the minimum size of C-terminal fragment peptides of NMB and GRP-10 to stimulate gastrin secretion was NMB (2–10) and GRP-10 (3–10), respectively. Both NMB and GRP-10 (0.1-100 nmol/l) stimulated insulin release from the isolated canine pancreas. The glucagon release was stimulated by 10 and 100 nmol/l GRP-10 and was not stimulated by the same doses of NMB. The somatostatin release was not influenced by either peptide. It is concluded that 1) NMB and GRP-10 can stimulate gastrin and pancreatic hormone secretion, and the latter effect may be mainly due to a direct action on the islet cells; 2) the stimulatory effect of GRP-10 is stronger than that of NMB. The difference in the minimal active fragment between NMB and GRP-10 suggests that the amino acid of position 3 – NMB (Leu) and GRP-10 (His) – may play an important role in their biological activity.
Exaggerated growth hormone response to growth hormone-releasing hormone in type I diabetes mellitus
Authors: Krassowski J. , Felber J. P. , Rogala H. , Jeske W. , Zgliczynski S.
Published: December 2008

Abstract. Excessive GH response to various stimuli has been frequently described in diabetes mellitus. We studied the GH response to a synthetic GHRH in a group of 16 non-obese Type I diabetic patients. GHRH (1–44) given as iv bolus at a dose of 50 μg induced a markedly greater GH response in the diabetic than in the normal subjects with peak values of 39.5 and 14.7 μg/l, respectively, and the differences were significant from 15 to 60 min. Peak GH level was 44.6 μg/l in diabetic patients without retinopathy and 34.2 μg/l in patients with retinopathy, but the difference was not significant. Peak GH levels did not correlate with metabolic control of disease estimated by basal glucoseand HbA1 levels nor with age, weight of the patients, and duration of the disease. It is concluded that Type I diabetic patients show an exaggerated GH response to GHRH and this response does not correlate with the metabolic control of diabetes.