bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth hormone specific stimulation of mitosis by size-fractionated serum from patients with growth hormone insufficiency: A study on the rat lymphoma cell line, Nb2
Authors: Luthman Marguerite , Wallerman Ella , Roos Paul , Werner Sigbritt 
Published: June 2009

Abstract.
The aim was to investigate the bioactivity of a high-molecular weight human growth hormone, identified following molecular sieve chromatography of serum. Nine patients with pituitary disease and GH insufficiency were studied. All patients had non-detectable levels of immunoreactive GH, <0.2 μg/l, in diurnal serum profiles. GH bioactivity was determined before and after size-fractionation of serum. The bioassay is based on the finding that a rat lymphoma cell line, Nb2, proliferates in the presence of lactogens. GH and PRL immunoreactivities were measured by radioimmunoassays. Pronounced GH immunoreactivity was found in fractions of sera from 7 out of the 9 patients and of 2 of 4 control sera, particularly in fractions corresponding to the elution volume of high-molecular weight proteins (>160 kD). PRL immunoreactivity was only detected in fractions corresponding to the elution volume of monomeric PRL. Unfractionated serum had a dose-dependent mitogenic effect on the Nb2 cells. GH-antibodies could not inhibit this effect. Fractions of serum obtained from the patients stimulated Nb2 cell division as well. The mitogenic effect of serum fractions could be inhibited by GH-antibodies. Thus, high-molecular weight GH circulating in patients with GH insufficiency were shown to exert a GH-specific bioactivity in vitro after size-fractionation.
Adenosine 3',5'-monophosphate in relation to inhibition of cervical smooth muscle activity in early pregnant women
Authors: Norström A. , Bryman I. 
Published: June 2009

Abstract.
Contractile activity was registered in strips of cervical tissue obtained by needle biopsy from women in the first trimester of pregnancy. Dibutyryl cyclic adenosine-3',5'-monophosphate (5 × 10−6mol/l), isobutyryl methylxanthine (10−4mol/l), and forskolin (10−510−4mol/l), the latter two drugs known to increase the levels of endogenous cAMP, inhibited spontaneous muscle activity. The levels of tissue cAMP were determined in strips during relaxation induced by prostaglandin E2 or purified porcine relaxin and compared with cAMP levels in strips from the same women during contractile activity. Exposure to prostaglandin E2 but not to relaxin was followed by increased levels of cAMP. It is suggested that cAMP has a role as a second messenger in the prostaglandin E2-mediated relaxation of cervical smooth muscle.
Presence of CRH-binding protein in amniotic fluid and in umbilical cord plasma
Authors: Suda Toshihiro , Iwashita Mitsutoshi , Sumitomo Takashi , Nakano Yoriko , Tozawa Fumiko , Demura Hiroshi 
Published: June 2009

Abstract.
CRH-binding protein was present in the amniotic fluid and in the umbilical cord plasma after 15 weeks and 24 weeks of pregnancy, respectively. The size of the CRH-binding protein was similar to that in the peripheral blood from normal subjects. The level of the binding of CRH-binding protein in the umbilical cord plasma during the third trimester of pregnancy was also similar to that in the peripheral blood of neonates and normal adult subjects. The binding of CRH-binding protein was temporarily decreased at 40 weeks of pregnancy. These results indicate that fetal CRH-binding protein seems to be produced at least in the second trimester of pregnancy.
Effect of insulin-like growth factor 1 on steroidogenesis in cultured human granulosa cells
Authors: Bergh Christina , Olsson Jan-Henrik , Hillensjö Torbjörn 
Published: June 2009

Abstract.
The effect of IGF-I on steroidogenesis in human granulosa cells was studied. Granulosa cells were obtained from follicles of both natural and stimulated cycles. The cells were cultured 4 to 6 days and the effect of IGF-I (1 to 100 μg/l) on basal, LH- and FSH-stimulated steroidogenesis was studied. It was found that in granulosa cells from follicles of natural cycles, FSH as well as IGF-I significantly stimulated progesterone and estradiol production in a majority of the experiments. A synergistic effect of FSH and IGF-I could be seen when low (1 and 10 μg/l) concentrations of the two hormones were used. Also in granulosa luteal cells from stimulated cycles a stimulatory effect of IGF-I on estradiol as well as progesterone production was observed. The present results suggest that IGF-I in combination with gonadotropins has a physiological role in the human follicle in controlling differentiation of the granulosa cells.
Muscarinic regulation of phospholipase A2 and iodide fluxes in FRTL-5 thyroid cells
Authors: Di Girolamo Maria , D'Arcangelo Daniela , Bizzarri Cinzia , Corda Daniela 
Published: June 2009

Abstract.
FRTL-5 thyroid cells express a muscarinic receptor which inhibits the phospholipase C activity in a pirenzepine-insensitive manner. We here report that the cholinergic agonist carbachol decreases in these cells the steady-state iodide content, an effect correlated with the iodination of thyroglobulin and with thyroid hormone formation. Several signal pathways may be involved in this phenomenon since carbachol in addition to inhibiting phospholipase C, increased the arachidonic acid release and modified the adenylyl cyclase activity. In FRTL-5 cells, arachidonic acid is released via the direct stimulation of phospholipase A2 by a pirenzepine-sensitive muscarinic receptor coupled to a GTP binding protein sensitive to pertussis toxin. Regarding adenylyl cyclase, carbachol potentiated the thyrotropin-induced stimulation of the enzyme, whereas it did not affect the basal levels of cAMP. In vitro binding studies revealed the presence of two muscarinic binding sites. To summarize, the analysis of signal pathways and of in vitro binding sites indicates a complex muscarinic regulation of thyroid function, which includes the modulation of iodide fluxes.
The influence of growth hormone and thyroxine on iodothyronine deiodinase activity in the liver, kidney and brown adipose tissue in hypophysectomized rats
Authors: Gøtzsche Liv S. Bjørn-Hansen , Flyvbjerg Allan , Marshall Sally , Jørgensen Karin D. , Weeke Jørgen 
Published: June 2009

Abstract.
The effects of GH and T4 substitution on peripheral iodothyronine deiodinase activity in the liver, kidney and brown adipose tissue of hypophysectomized rats were investigated. Animals were treated with GH (140 μg hGH/day), T4 (3 μg/day), GH plus T4 (same doses), or saline. Rats were killed 0, 4, 7 or 11 days after treatment was started. Non-hypophysectomized, age matched rats were killed after 0 and 11 days and served as controls. GH plus T4 restored body weight gain to normal, whereas GH alone and T4 alone did not. Tissue deiodinase activity and T3 concentrations were severely depressed in the hypophysectomized rats compared with non-hypophysectomized controls (to less than 10%). GH substitution in hypophysectomized rats led to a slight but significant elevation in tissue iodothyronine deiodinase activity in the liver and kidney, without concomitant increases in T3. Deiodinase activity in brown adipose tissue did not differ from that in saline-treated controls. T4 administration normalized deiodinase activity and tissue T3 content in all the evaluated tissues. GH plus T4 resulted in a lesser increase in deiodinase activity than T4 alone in the liver and kidney (p<0.01 at day 11), whereas no significant difference was observed in brown adipose tissue. In conclusion, GH stimulates iodothyronine deiodinase activity of the liver and kidney in hypophysectomized rats. Moreover, when GH is administered together with T4, the T4-stimulated enzyme activity in the liver and kidney is downregulated, suggesting that GH attenuates (or modulates) the T4 effect on this specific enzyme activity.
Evidence for a pathological reduction in brain dopamine metabolism in idiopathic hyperprolactinemia
Authors: Paradisi Roberto , Grossi Gabriele , Pintore Angela , Venturoli Stefano , Porcu Eleonora , Capelli Maurizio , Flamigni Carlo 
Published: June 2009

Abstract.
The role of brain catecholamine activity in the neuroendocrine regulation of the dopamine-PRL system in idiopathic hyperprolactinemia was investigated by high-performance liquid chromatography with electro-chemical detector. We measured urinary dopamine, norepinephrine, epinephrine, vanillylmandelic acid, homovanillic acid, 3,4-dihydroxyphenylacetic acid and total 3-methoxy-4-hydroxyphenylglycol levels in 12 women with idiopathic hyperprolactinemia before and during either peripheral dopa-decarboxylase blockade, by carbidopa, or dopamine β-hydroxylase blockade, by disulfiram. Homovanillic acid and 3,4-dihydroxyphenylacetic acid concentrations were significantly lower (p<0.001 and p<0.005, respectively) in patients with idiopathic hyperprolactinemia compared with those in 12 control subjects in the early follicular phase, whereas they were similar to those in the control subjects in the pre-ovulatory phase. Dopamine, norepinephrine, epinephrine, vanillylmandelic acid and 3-methoxy-4-hydroxyphenylglycol concentrations were similar to those of the control subjects in both phases of the cycle. During carbidopa administration the levels of all urinary catecholamines and metabolites were unchanged, except that of dopamine which dropped remarkably (p<0.001). During disulfiram administration dopamine, homovanillic acid and 3,4-dihydroxyphenylacetic acid concentrations increased (p<0.05, p<0.001 and p<0.005, respectively) and those of norepinephrine, vanillylmandelic acid and 3-methoxy-4-hydroxyphenylglycol decreased (p<0.05, p<0.001 and p<0.005, respectively), whereas epinephrine levels remained unaltered. These data support the existence of a quantitatively reduced brain dopamine activity in idiopathic hyperprolactinemia.
The interaction of GHRH with TRH in acromegaly: a controlled study
Authors: Looij Bert-Jan , Roelfsema Ferdinand , Frölich Marijke , Kruseman Arie C. Nieuwenhuijzen 
Published: June 2009

Abstract.
In a single-blind placebo-controlled study, the effect of an iv bolus injection of 100 μg GHRH(1–29)NH2 on the response to 200 μg TRH was assessed in 10 untreated patients with acromegaly to determine whether GHRH interacts with TRH in acromegaly, as previously described in healthy subjects. The combination of GHRH(1–29)NH2 with TRH resulted in a larger increment of peak and of integrated plasma TSH and PRL levels than after TRH alone. GHRH alone had no effect on TSH secretion and only a modest effect on PRL secretion. These findings suggest that in acromegaly, like in healthy individuals, GHRH potentiates the TSH response to TRH and that the effects of GHRH and TRH on PRL secretion are additive.
Stimulation of steroid secretion by adrenocorticotropin injections and by arginine vasopressin infusions: no evidence for a direct stimulation of the human adrenal by arginine vasopressin
Authors: Bähr V. , Hensen J. , Hader O. , Bölke T. , Oelkers W. 
Published: June 2009

Abstract.
Arginine vasopressin stimulates the secretion of adrenocorticotropin. A direct stimulatory effect of AVP on cortisol as well as aldosteron secretion has been postulated by several investigators. To study the possible role of a direct stimulatory action of AVP on the adrenal cortex, normal volunteers were treated with incremental injections of ACTH or with incremental infusions of AVP which raised plasma AVP levels to a maximum of 256±16 pmol/l. In both situations, a significant (p<0.001) linear correlation between plasma ACTH and plasma cortisol was observed. The regression coefficients were not different (p>0.5). Plasma aldosterone was stimulated by both treatments, but the weakly positive correlation between plasma ACTH and plasma aldosterone was not significant for either stimulus. Thus, in man, a direct stimulatory effect of AVP on cortisol secretion cannot be demonstrated. A direct effect of AVP on aldosterone cannot be definitely excluded, but is certainly of minor importance.
Acute and long-term effects of once-daily oral bromocriptine and a new long-acting non-ergot dopamine agonist, quinagolide, in the treatment of hyperprolactinemia: A double-blind study
Authors: Verhelst J. A. , Froud A. L. , Touzel R. , Wass J. A. H. , Besser G. M. , Grossman A. B. 
Published: June 2009

Abstract.
Quinagolide (CV 205-502, Sandoz), an octahydrobenzo (g) quinoline, is a new non-ergot dopamine agonist which has specific D2 receptor activity and a long half-life, making it suitable for once-daily treatment. Recent uncontrolled reports have suggested that quinagolide may be successfully used for the clinical management of hyperprolactinemia with fewer adverse reactions than bromocriptine. This study is the first to compare quinagolide in a double-blind manner with bromocriptine, given only once-daily instead of the usual multidose regimen. In the first phase we compared, in 7 hyperprolactinemic patients, the effects over 24 h of a single oral dose of 0.05 mg quinagolide with 2.5 mg bromocriptine. Compared with placebo, both bromocriptine and quinagolide showed potent PRL-inhibiting and GH-releasing effects, with comparable effects at 24 h; no significant changes were observed in TSH, LH, FSH or cortisol. Twelve hyperprolactinemic patients were then randomized to receive either once-daily bromocriptine or quinagolide in incremental doses for a period of six months. Both drugs were found to be equally effective, and no differences were seen either in adverse reactions or PRL levels during repeated diurnal sampling. We therefore conclude that quinagolide and bromocriptine are therapeutically equivalent in long-term use, and both are equally effective when given once a day. However, some patients intolerant of bromocriptine may respond better to quinagolide, and vice versa.
Thyroid epithelial cell proliferation in xenotransplanted human toxic nodular goitre is increased by Graves' IgG
Authors: Smeds Staffan , Jörtsö Erik , Tegler Lennart 
Published: June 2009

Abstract.
Human toxic nodular goitre tissue was xenotransplanted to athymic mice. Transplant function was analysed as 18-h thyroid transplant uptake of iodide-125 at day 21 and again at 10 weeks after transplantation. Graves' IgG or IgG from healthy donors was given intraperitoneally daily day 22-35. Epithelial cell proliferation in thyroid tissue transplants from human toxic nodular goitre and from normal thyroid glands was analysed by continuous [3H]thymidine administration for 4 days between day 21 and 24 and for 12 days between day 21 and 33 in separate series given daily injections of Graves' IgG or normal IgG during the same period. After administration of Graves' IgG, the 18-h iodide-125 uptake by the toxic nodular tissue transplants was 7 times higher at 10 weeks than at 3 weeks. Control IgG gave a corresponding 1.6-fold increase. The fraction of labelled cells after [3H]thymidine incorporation was 18 and 56% in toxic nodular goitre transplants and 4 and 48% in normal thyroid tissue transplants after daily Graves' IgG administration for 4 and 12 days, respectively, but only 1.3% in both types of tissue transplants after administration of normal IgG. Graves' IgG therefore seems to be able to stimulate cell proliferation in toxic nodular goitre tissue.
Congenital hypothyroidism in two cats due to defective organification: data suggesting loosely anchored thyroperoxidase
Authors: Sjollema B. E. , den Hartog M. T. , de Vijlder J. J. M. , van Dijk J. E. , Rijnberk A. 
Published: June 2009

Abstract.
Two cats with congenital hypothyroidism are described. In vivo discharge of accumulated labelled iodide by perchlorate administration revealed defective organification of iodide, which was complete in one cat and partial in the other. In the cat with the partial organification defect, thyroid tissue was obtained for biochemical studies. No membrane-bound peroxidase activity could be demonstrated. The activity was found in the 100000 × g supernatant. It is suggested that the loose enzyme anchoring caused decreased availability of peroxidase and as a consequence reduced capacity for organic binding of trapped iodide.
Regional stimulation of thyroid epithelial cells in Graves' disease by lymphocytic aggregates and plasma cells
Authors: Paschke Ralf , Brückner Norbert , Eck Thomas , Schaaf Ludwig , Back Walter , Usadel Klaus Henning 
Published: June 2009

Abstract.
The significance of intrathyroidal lymphocytic infiltration is not known. However, several indirect lines of evidence suggest that interstitial or intraepithelial lymphocytes are the effector or thyroid autoantibodyproducing lymphocytes in Graves' disease. This has not been investigated in vivo. Changes of nuclear volume of endocrine cells have previously been shown to be a reliable parameter of functional stimulation of endocrine glands. Therefore we investigated this parameter near and off lymphocytic aggregates, loosely distributed plasma cells and memory T cells in paraffine sections of Graves' disease thyroid glands. In 21 Graves' disease thyroid glands we found significant increases of thyroid epithelial cell nuclear volume near plasma cells (198.4 μm3) as well as near lymphocytic aggregates (219.1 μm3) compared with thyroid epithelial cell nuclear volume one microscopic field away (160.1 and 137.7 μm3 respectively). Similar nuclear volume differences were observed after propanolol and thiourelene antithyroid drug treatment. These nuclear volume differences could not be observed in 10 control thyroid glands and around CD45R0-positive memory T cells in Graves' disease thyroid glands. These direct in vivo investigations of regional functional stimulation of thyroid epithelial cells in Graves' disease show local stimulation near lymphocytic aggregates and diffusely distributed plasma cells. Therefore our in vivo data do not permit to identify stimulatory lymphocytes only interstitially or intraepithelially as previously suggested.
Results of external pituitary irradiation after unsuccessful transsphenoidal surgery in Cushing's disease
Authors: Vicente A. , Estrada J. , de la Cuerda C. , Astigarraga B. , Marazuela M. , Blanco C. , Lucas T. , Barceló B. 
Published: June 2009

Abstract.
Fourteen adult patients (10 females and 4 males; age range 20-60 years) with persistent Cushing's disease after transsphenoidal microsurgery were treated with pituitary irradiation. Supervoltage multiportal administration was employed at a total dose of 50 Gy (±0.65 sd). The interval between microsurgery and pituitary irradiation was less than 6 months in 6 patients and more than 6 months in 8. The pituitary-adrenal axis was evaluated postsurgically, before irradiation and every 6 months thereafter. The remaining anterior pituitary function was simultaneously tested. Remission rates at 12 months and 24 months after radiotherapy were 61 and 70%, respectively. Two patients developed TSH deficiency and another gonadotropin deficiency during the follow-up after radiation. We conclude that pituitary irradiation is the treatment of choice for persistent Cushing's disease after unsuccessful surgery because of its high efficiency and low incidence of adverse reactions when compared with other forms of treatment.
Different binding of stimulatory-type and blocking-type TSH receptor antibody with guinea-pig testis membrane
Authors: Inui T. , Ochi Y. , Hachiya T. , Chen W. , Nakajima Y. , Kajita Y. , Ogura H. 
Published: June 2009

Abstract.
A receptor assay using [125I]bTSH-binding to guinea-pig testis membrane was developed. Unlabelled hCG and FSH inhibited [125I]bTSH binding. In patients with Graves' disease and in untreated hyperthyroid patients, almost all long-acting thyroid stimulators and thyroid-stimulating antibodies, respectively did not inhibit [125I]bTSH binding, which on the other hand was inhibited by thyroid stimulation blocking antibodies in patients with primary hypothyroidism. When the inhibitory effect on the binding of [125I]hCG and 125I-synthetic α-subunit peptide (α26-46) of hCG to testis membrane was examined, bTSH resulted in a significant inhibition. However, all three kinds of TSH receptor antibodies had no inhibitory effect. This study demonstrated 1. interaction of α-subunit of TSH and hCG with the testicular receptor; 2. binding of thyroid stimulation-blocking antibody and lack of binding of thyroid-stimulating antibody to the testicular TSH receptor in spite of binding of these TSH receptor antibodies to the thyroidal TSH receptor, and 3. lack of binding of thyroid-stimulating antibody and thyroid stimulation-blocking antibody to the testicular gonadotropin receptor.
Calcitriol receptors in rat thyroid follicular cells (FRTL-5)
Authors: Berg Jens P. , Torjesen Peter A. , Haug Egil 
Published: June 2009

Abstract.
The FRTL-5 cell line is widely used as a model for normal thyroid follicular cells. These cells have retained their ability to alter cAMP production, cell proliferation, iodine uptake, and thyroglobulin synthesis in response to thyrotropin. We have previously shown that calcitriol attenuated both basal and TSH stimulated cAMP production dose-dependently in FRTL-5 cells. Cytosol fractions (105000 g, 60 min, 4°C) prepared from FRTL-5 cell homogenates possessed calcitriol-binding components with a sedimentation coefficient of approximately 3.7 S in high salt (0.3 mol/l KCl) sucrose gradients (5–20%). At 4°C, specific binding increased rapidly during the first 4 h and reached a plateau after 8 h. The specific binding (18 h, 4°C) was maximal at a [3H]calcitriol concentration of approximately 0.5 nmol/l. Scatchard analysis of the binding data indicated one single class of high affinity binding sites with Kd = 105±2 pmol/l and Bmax=38.5±4.7 pmol/g cytosol protein (mean ± sd, N=6). In conclusion, our results suggest that the FRTL-5 cells possess functional receptors for calcitriol with the same physicochemical properties as the receptors found in normal rat tissues.
Expression of GH receptor mRNA in regenerating skeletal muscle of normal and hypophysectomized rats. An in situ hybridization study
Authors: Jennische Eva , Andersson Göran L. 
Published: June 2009

Abstract.
Expression of growth hormone receptor mRNA was investigated by in situ hybridization in skeletal muscle from normal and hypophysectomized rats during the first seven days of regeneration after ischemic injury. A digoxigenin-labelled RNA probe directed against the extracellular part of the rat GH receptor was used. In both normal and hypophysectomized rats distinct expression of GH receptor mRNA could be demonstrated in the regenerating muscle cells at the myoblast/myotube stage. The GH receptor expression appeared to decline with increasing maturation of the regenerated muscle fibres. In hypophysectomized rats, the regeneration process and the expression of GH receptor mRNA was delayed compared with that in normal animals. It is concluded that growth hormone may affect also the early phase of muscle regeneration in normal animals. To what extent lack of growth hormone contributes to the delayed regeneration observed in the hypophysectomized rats remains to be elucidated.