bluuebunny/crossref_metadata_2025_split huggingface dataset:
Somatomedin A increments are diminished in acromegaly with concomitant hyperprolactinaemia
Authors: Hulting A.-L. , Hall K. , Werner S. 
Published: December 2008

Abstract. The influence of prolactin (Prl) on growth hormone (GH) regulated somatomedin A (SMA) levels was studied in 30 patients with acromegaly before and after transsphenoidal pituitary surgery. Pre-operative GH levels were elevated in all patients and SMA levels in all but one patient. Eleven patients (33%) showed hyperprolactinaemia. There was no correlation between GH and SMA levels. Plasma GH did not differ in patients with GH and Prl producing adenomas compared to those with isolated GH hypersecretion. SMA levels, however, were significantly lower in patients with hyperprolactinaemia than in those with normal serum prolactin (P < 0.001).
After surgery GH decreased in all and SMA levels in all but one patient. Despite similar post-operative GH levels SMA decreased to significantly lower levels in patients with combined hypersecretion of GH and Prl compared to patients with normal prolactin levels (P < 0.05). Nine of the 11 patients with hyperprolactinaemia showed normal Prl after surgery.
The SMA levels in patients with acromegaly seem to be suppressed in patients with pre-operatively concomitant hyperprolactinaemia before as well as after adenomectomy regardless of the normalization of Prl. Our findings offer one explanation ot the lack of correlation between SMA and GH levels in acromegaly.
The differential diagnostic problems in unilateral euthyroid Graves' ophthalmopathy
Authors: Perrild Hans , Feldt-Rasmussen Ulla , Bech Karine , Ahlgren Preben , Hansen Jens Mølholm 
Published: December 2008

Abstract. Nine consecutive patients with unilateral ophthalmopathy with suspected endocrine pathogenesis were investigated with a TRH test, a T3 suppression-test, thyroid autoantibodies and a subsequent computerized tomography (CT)-scan. All patients were clinically and biochemically euthyroid. Seven of 9 patients had a normal TRH test and 6 of 7 had a normal T3 suppression test. Slightly to moderately elevated microsomal and thyroglobulin (determined with radioimmunoassay) autoantibodies were found in 5 of 8 patients and in 1 patient thyroid stimulating immunoglobulins (TSI) were found. Three of the patients had normal thyroid function tests and no detectable thyroid autoantibodies. The subsequent CT-scan revealed that one of these had a maxillary tumour protruding into the orbita. The remaining 8 patients had enlargement of one (3 patients) or more (5 patients) eyemuscles. Two of the 8 patients had bilaterally enlarged eyemuscles, one of which was the patient with positive TSI. The remaining 6 patients had unilateral extraocular muscle enlargement. Thus, 2 of 9 patients had ophthalmopathy without thyroid dysfunction so-called isolated autoimmune ophthalmopathy or Graves' ophthalmopathy.
Thyroid function tests seem to be of limited value in the diagnosis between endocrine and non-endocrine eye disease, and we recommend the use of diagnostic imaging (e.g. CT-scan) in patients with unilateral exophthalmus in order to diagnose malignant processes.
Diabetes mellitus in phaeochromocytoma Fasting blood glucose levels before and after surgery in 60 patients with phaeochromocytoma
Authors: Stenström Gunnar , Sjöström Lars , Smith Ulf 
Published: December 2008

Abstract. Sixty patients undergoing operation for phaeochromocytoma were investigated in the pre- and postoperative states with respect to fasting blood glucose levels. When 6 previously known or suspected diabetics were excluded, preoperative diabetes (fasting blood glucose levels ≥ 7.0 mmol/l) were found in 3 of 13 (23%) with sustained hypertension, in 6 of 12 (50%) with sustained hypertension associated with paroxysms and in 4 of 24 (17%) with paroxysmal hypertension. None of the 5 patients with atypical clinical symptoms had glucose levels ≥ 7.0 mmol/l. In the groups of patients with particularly high urinary excretion of catecholamines and vanilmandelic acid higher blood glucose levels were also found. The postoperative blood glucose levels in the follow-up study were normal and < 5.8 mmol/l in all cases except in 3 of the 4 still living patients with a previously known diabetes and in 1 patient with a malignant tumour.
Thus, manifest diabetes, defined as fasting glucose levels ≥ 7.0 mmol/l, is frequently present in patients with phaeochromocytoma (24% in the present study) and the diabetes is reversed by removal of the tumour.
Abnormality of testicular FSH receptors in infertile men
Authors: Namiki M. , Koide T. , Okuyama A. , Sonoda T. , Itatani H. , Miyake A. , Aono T. , Terada N. , Matsumoto K. 
Published: December 2008

Abstract. To ascertain whether abnormalities in testicular binding of follicle stimulating hormone (FSH) are related with spermatogenic impairment found in idiopathic male infertility, we measured FSH receptors in testicular tissues obtained by biopsy from 37 infertile men.
Since there had been few reports on the characterization of human testicular FSH receptors, we first established conditions for FSH receptor assay in small amounts of human testicular tissues taken by biopsy. Thirty-seven infertile men were divided into 3 groups by histological grading using Johnsen's score count, and testicular FSH receptors among these groups were compared. Although 6 of 12 infertile men with low Johnsen's score count and 3 of 9 men with middle score count had no obvious FSH binding sites with high affinity, all 16 men with high score count had high affinity FSH binding sites.
The present findings demonstrate that the decrease in testicular high affinity binding sites for FSH is related with the degree of spermatogenic impairment found in idiopathic male infertility.
Lack of melatonin action on testosterone production by superfused rat interstitial cells
Authors: Jarrige Jean-Francois , Thieblot Philippe , Boucher Daniel 
Published: December 2008

Abstract. The direct effect of increasing doses of melatonin (10−8 to 10−5 m) on testosterone production by superfused rat interstitial cells was studied.
A constant basal testosterone output was observed for approximately 3 h after the initial high release. A continuous hypothalamo-pituitary stimulation induced a rapid testosterone response reaching peak values in 40–60 min, then decreasing progressively. Basal testosterone release was not modified by 20 or 140 min melatonin infusions. Furthermore, melatonin induced no alteration of the stimulative testosterone response when directly infusing the cells. This study demonstrates that melatonin in vitro has no direct effect on testosterone production by adult rat interstitial cells. It would seem, therefore, that the well known inhibitory influence of melatonin on rat reproductive function is not produced by a direct effect on Leydig cells.
Specific receptors for epidermal growth factor in human bone tumour cells and its effect on synthesis of prostaglandin E2 by cultured osteosarcoma cell line
Authors: Hirata Yukio , Uchihashi Masahito , Nakashima Hiroko , Fujita Takuo , Matsukura Shigeru , Matsui Katsuaki 
Published: December 2008

Abstract. Using tumour cell lines derived from human bone tumours, specific binding sites for epidermal growth factor (EGF), a potent growth stimulator in many tissues, and its effect on synthesis of prostaglandin (PG) E2, a potent bone-resorbing factor, by cultured osteosarcoma cell line were studied.
Three tumour cell lines, one osteosarcoma (HOSO) and two giant cell tumours of the bone (G-1 and G-2), all possessed specific binding sites for 125I-labelled EGF: the apparent dissociation constant was ~4–10 × 10−10 m and the maximal binding capacity was 50 000–80 000 sites/cell. EGF had no mitogenic effect in these cell lines. However, these cell lines did not have specific binding sites for 125I-labelled parathyroid hormone (PTH) or calcitonin. HOSO line produced and secreted PGE2 into medium, while no significant amount of PGE2 was demonstrated in G-1 or G-2 line. EGF significantly stimulated PGE2 production in HOSO line in a dose-dependent manner (0.5–50 ng/ml); its stimulatory effect was completely abolished by indomethacin, an inhibitor of PG biosynthesis. Exogenous PGE1 significantly stimulated cyclic AMP formation in HOSO line, whereas PGF2α, PTH, calcitonin, or EGF had no effect. None of these calcium-regulating hormones affected cyclic AMP generation in either G-1 or G-2 line.
These data indicate that human bone tumour cells have specific EGF receptors unrelated to cell growth, and suggest that EGF may be involved in bone resorption through a PGE2-mediated process in human osseous tissues.
Infarction of FSH-secreting pituitary adenoma
Authors: Koršić Mirko , Lelas-Bahun Nada , Šurdonja Pavle , Bešenski Nada , Horvat Stjepan , Plavšić Vesna 
Published: December 2008

Abstract. A patient with an FSH-producing adenoma is reported. Two hours after LRH administration (100 μg iv) the clinical signs of tumour infarction developed. The patient followed a severe clinical course. FSH levels normalised but further deterioration of pituitary function was documented. Worsening of the vision without improvement after surgical resection of the adenoma was observed.
The role of LRH testing in adenoma infarction is discussed.
Dynamic testing of prolactin and growth hormone secretion in patiens with neuroendocrine disorders
Authors: Müller E. E. , Cavagnini F. , Martinez-Campos A. , Maraschini C. , Giovannini P. , Novelli A. , De Leo V. 
Published: December 2008

Abstract. Prolactin (Prl) and growth hormone (GH) responses to different pharmacologic probes acting at the central nervous system (CNS) or the anterior pituitary (AP) level were evaluated in patients with distinct neuroendocrine disorders. Thirteen patients with Prl-secreting tumours (PST), 10 acromegalics (A) and 8 patients with hypothalamic lesions (HL), as assessed on clinical, radiological and surgical grounds, underwent on separate occasions acute testing with the opioid peptide FK 33-824 (0.5 mg iv), the indirect dopamine (DA) agonist nomifensine (NOM, 200 mg po), the DA receptor antagonist domperidone (DOM, 10 mg iv), TRH (200 μg iv) and insulin (ITT, 0.10-0.15 IU/kg iv). All patients were evaluated pre-surgery and 4 of them also post-surgery. Prl and GH were evaluated by RIA at different time intervals following treatments.
Peculiar features of Prl and GH response could be evidenced in the patients as follows: Prl: PST patients did not respond either to stimulation by FK 33-824 (12/13) or to inhibition by NOM, (9/10), but 2/8 and 4/12 of them did respond to DOM or TRH stimulation, respectively; 8/10 A and all of the HL patients did not suppress plasma Prl following NOM, but many of them did respond to FK 33-824 (6/10 A, 5/8 HL) and TRH (9/10 A, 6/8 HL); as for GH, PST patients could be divided into FK 33-824 responders (8/12) and non-responders, whereas in only one of the A and in none of the HL patients a consistent response to the peptide was present; a major difference between A and HL patients was the ability of TRH to elicit a GH rise in the former (8/10) but not the latter (0/6). In conclusion, concomitant application of different CNS- or AP-acting stimuli seems to enable better functional connotation of individual disorders, and hence, provide information of value for the underlying pathophysiology.
Characterization of growth hormone release in response to external heating Comparison to exercise induced release
Authors: Christensen Stig Engkjær , Jørgensen Otto Lunde , Møller Niels , Ørskov Hans 
Published: December 2008

Abstract. The effects of increases in body temperature on growth hormone (GH)-release were studied in 10 young normal males in the fasting state as well as postprandially.
The temperature increase of one degree centigrade was attained by external heating using thermostatically controlled water blankets covered by heat-reflecting aluminium foil. The increase in plasma GH after heating was partially suppressed in the non-fasting state reaching a mean of 7.9 ± 3.5 (sem), ng/ml, range 1.0–36 ng/ml. In contrast all subjects exhibited higher increases, mean 18.3 ± 4.0 ng/ml, range 7–44 ng/ml, in response to heating when fasting.
The results were compared in the same subjects to the plasma GH-responses obtained during exercise (450 kpm/min for 40 min) inducing a similar increase in body temperature of about one degree centrigrade. Nevertheless the response in plasma GH (8.4 ± 3.3 ng/ml, range 0.4–34 ng/ml) was smaller than obtained by the heat test despite a rate of temperature increase on exercise which was about twice as high. Furthermore, the same exercise performed in a cold room under circumstances which precluded any major rises in core temperature resulted in complete inhibition of GH-release. The results indicate that exercise per se does not stimulate GH-secretion, indeed it may inhibit the response expected to be evoked by the exercise-induced rise in temperature.
Evidence is also presented that it is core and not cutaneous temperature which modulated GH release.
The procedure used for inducing the rise in temperature and plasma GH may be used as a simple, acceptable and safe clinical test for GH-insufficiency.
Age-related alterations of pituitary-thyroid function in normal female subjects and in female patients with simple goitre
Authors: Yamada Takashi , Naka Motoji , Komiya Ichiro , Ichikawa Kazuo , Aizawa Toru , Hashizume Kiyoshi , Takasu Nobuyuki , Watanabe Takuji 
Published: December 2008

Abstract. Age-related alterations in pituitary-thyroid function were studied in 173 female patients with simple goitre and in 70 normal female subjects. They were divided into 4 groups according to age: A group, less than 19 years; B group, 20 to 29 years; C group, 30 to 39 years; D group, 40 to 59 years.
Serum triiodothyronine (T3) concentrations decreased progressively but insignificantly with age in female patients with simple goitre and in normal female subjects, whereas serum thyroxine (T4) concentrations remained constant throughout the studied age range. Only in female patients with simple goitre, did basal serum TSH concentrations show a tendency to increase with age. However, thyrotrophin-releasing hormone (TRH)-stimulated increase of serum TSH was progressively augmented with age both in female patients with simple goitre and in normal female subjects; the magnitude of change was greater in the former group.
As reflected by acute increases of serum T3 and T4 concentrations, thyroidal responsiveness to endogenous TSH was progressively depressed with age in female patients with simple goitre and in normal female subjects. This age-related thyroidal refractoriness to TSH was more apparent when the changes were expressed as ΔT3(stimulated T3 – basal T3)/ΔTSH (maximum TSH after TRH – basal TSH), and ΔT4(stimulated T4 – basal T4)/ΔTSH. ΔT4/ΔTSH was lower in female patients with simple goitre than in normal female subjects in all age groups. However, the difference was significant only for ΔT4/ΔTSH in group A. Thyroidal responsiveness to exogenous TSH also gradually declined with age in female patients with simple goitre.
Our data indicate 1) TRH-stimulated TSH secretion increases with age probably to overcome age-related thyroidal refractoriness to TSH and 2) although the thyroid of patients with simple goitre is slightly less responsive to TSH than that of normal subjects for all age groups, the difference was significant only for young patients.
Serum sex hormone-binding globulin during puberty in girls and in different types of adolescent menstrual cycles
Authors: Apter D. , Bolton N.J. , Hammond G. L. , Vihko R. 
Published: December 2008

Abstract. Serum sex hormone binding globulin (SHBG) concentrations were measured by an immunoradiometric assay, as part of a longitudinal study of puberty in girls, and were related to age. pubertal stage, age at menarche, weight, nature of the menstrual cycle and serum concentrations of sex steroids. A slow but very significant decrease was seen in SHBG from 77 nmol/l at 8–10 years of age to about 50 nmol/l after 15 years of age. Serum SHBG concentrations showed weak negative correlations with those of androstenedione and testosterone during puberty. The closest associations found between SHBG and the parameters measured were negative correlations with weight and body fat percentage in both pre-menarcheal and post-menarcheal girls, even after the effect of age was accounted for by calculating partial correlation coefficients. Girls who experienced early menarche (before 13.0 years) had lower SHBG but higher oestradiol serum concentrations at 10.0–15.9 years of age compared to girls with later menarche. In ovulatory menstrual cycles, a significant increase in SHBG was found from the early to the late part of the cycle, whereas no changes took place in anovulatory cycles. Serum concentrations of SHBG showed positive correlations with those of oestradiol and progesterone in specimens taken in the late part of the cycle.
In view of the weak relationships between serum SHBG and sex steroid concentrations, and the strong relationships between SHBG, weight and body fat percentage, factors other than steroids have to be considered in the regulation of SHBG levels during puberty.
Growth hormone releasing factor infusion does not sustain elevated GH-levels in normal subjects
Authors: Losa Marco , Bock Lilian , Schopohl Jochen , Stalla Günter K. , Müller O. Albrecht , von Werder Klaus 
Published: December 2008

Abstract. To evaluate the dynamics of GH-secretion after infusion of growth hormone releasing factor, human pancreatic growth hormone releasing factor (hpGRF1-44) was infused over 2 and 5 h at a dosage of 100 μg hpGRF1-44/h into 11 healthy subjects. The infusion was started and terminated with a 50 μg hpGRF1-44 bolus injection. In 5 subjects 200 μg TRH was given 4 h after starting the infusion. In addition, 4 healthy subjects received 50 μg hpGRF1-44 bolus injection every 2 h. GRF, somatostatin, GH, Prl, and TSH were measured by radioimmunoassay.
The initial 50 μg GRF bolus increased GH-levels in all 11 subjects with a maximum at 30 min (24.1 ± 5.1 ng/ml ± se). However, though hpGRF1-44 was continuously infused and GFR-levels remained elevated, GH decreased to a minimum 270 min after start of infusion (2.6 ± 0.6 ng/ml). The GH-response to the second bolus at the end of the infusion was lower compared to the first response (14.6 ± 3.4 ng/ml after 2 h and 7.6 ± 2.5 ng/ml after 5 h). TRH did not lead to a GH-increase during hpGRF1-44 infusion though Prl and TSH rose normally. The intermittent bolus injection of 50 μg hpGRF1-44 led to continuously decreasing GH-responses to the same GRF-dosage (I. bolus: 16.5 ± 1.6 ng/ml; II. bolus: 4.2 ± 0.8 ng/ml; III. bolus: 3.4 ± 0.5 ng/ml). No change in somatostatin levels was observed.
These findings show that GRF infusion or bolus injection in short intervals does not sustain elevated GH-levels. Pituitary GH is either not readily available for continuous GRF-stimulation or GH-secretion may be antagonized by increasing portal somatostatin levels which are not reflected in the peripheral circulation.
Effect of insulin on porcine granulosa cells: implications of a possible receptor mediated action
Authors: Otani Tetsuo , Maruo Takeshi , Yukimura Nobuyuki , Mochizuki Matsuto 
Published: December 2008

Abstract. The mechanism of direct action of insulin on porcine granulosa cells cultured in vitro was investigated. Specific receptors for insulin with two classes of binding sites were present. No significant difference in receptor characteristics was observed between granulosa cells obtained from small (1–2 mm), medium (3–5 mm) or large (6–11 mm) follicles. Insulin (25 mIU/ml) augmented both basal and hCG-stimulated progesterone secretion. Insulin was also essential for hCG-stimulated morphological luteinization of cultured porcine granulosa cells obtained from small follicles. Furthermore, 2 h preincubation with insulin (100 mIU/ml) increased glucose incorportation by cultured porcine granulosa cells as determined by pulsing with d-[14C](U)-glucose. The same dose of insulin also stimulated the glucose-6-phosphate independent form of glycogen synthase.
These results suggest that porcine granulosa cells possess insulin receptors and that insulin, mediated by its specific receptors, enhances glucose metabolism by stimulating glycogen synthase. Thus, insulin may play a pivotal role in morphological and funtional differentiation of porcine granulosa cells.
Involvement of endogenous prostaglandins in salt-induced hypertension
Authors: Ogihara Toshio , Gotoh Seiji , Tabuchi Yoshikatsu , Kumahara Yuich 
Published: December 2008

Abstract. Insufficient production of prostaglandins, which are possible antihypertensive agents, may be a pathogenetic factor in hypertensive patients on salt loading. We compared the levels of plasma PGE2, plasma renin activity (PRA) and urinary 6-Keto-PGF1α (6-O-PGF1α), a major stable metabolite of PGI2, on day 5 of salt deprivation and also on day 5 of subsequent salt loading in 17 patients with essential hypertension.
Salt loading decreased plasma PGE2, and slightly increased urinary 6-O-PGF1α. On salt loading, a positive correlation was found between the levels of plasma PGE2 and urinary sodium excretion. On salt deprivation, PRA was significantly correlated with plasma PGE2. The per cent change in mean blood pressure on changing from salt restriction to salt loading was inversely correlated with the per cent change in PGE2, and positively correlated with the per cent change in 6-O-PGF1α excretion.
These findings suggest that on salt restriction, PGE2 is involved in the renin-angiotension system and that on salt loading, PGE2 is produced to compensate for the excessive sodium. The finding that PGE2 production was attenuated progressively as the mean blood pressure increased on salt loading in patients with essential hypertension suggests that insufficient compensatory PGE2 production is a pathogenetic factor in salt-induced hypertensive patients. In contrast, PGI2 may be produced adaptively to regulate blood pressure during changes in salt balance.
Epidermal growth factor stimulates secretion of rat pituitary luteinizing hormone in vitro
Authors: Miyake Akira , Tasaka Keiichi , Otsuka Shirou , Kohmura Hiroko , Wakimoto Hiroshi , Aono Toshihiro 
Published: December 2008

Abstract. The effects of epidermal growth factor (EGF) on pituitary luteinizing hormone (LH) release and on the releases induced by oestradiol (E2) and LH-releasing hormone (LRH) were examined in a sequential double chamber perifusion system. In this system the mediobasal hypothalami (MBH) and/or pituitaries excised from normally cycling female rats in dioestrus were perifused with test media.
Perifusion with EGF at 1 ng/ml for 30 min induced significant release (80–100% increase, P <0.05) of LH from hypothalamo-pituitary pairs, but not from the pituitary alone. Perifusion of the pituitary alone with medium containing 1 ng/ml EGF, resulted in significant release of LH (70–140% increase, P < 0.05) after adminnistration of 10−7 m E2, but did not significantly influence LH release in response to 20 ng/ml LRH.
These findings suggest that EGF may be involved in the regulation of pituitary gonadotrophin secretion by a direct effect on the hypothalamus and indirectly by increasing the pituitary responsiveness to E2.