bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in the biomechanical properties of skin and aorta induced by corticotrophin treatment
Authors: Oxlund H.
Published: December 2008

The work presented here is an investigation of the effect of elevated levels of corticosteroids on the biophysical properties of skin, aorta and muscle tendon. Rats were given corticotrophin injections for 10, 30 and 60 days to elevate the level of plasma endogenous corticosteroids. The corticotrophin treatments did not change the water or collagen content of specimens from dorsal skin, thoracic aorta and peroneal muscle tendons, tested mechanically. Changes became evident after longer treatment times. For both skin and aorta, the tensile strength, elastic stiffness and failure energy were increased after 60 days of treatment. The corticotrophin treatment did not influence the mechanical properties of muscle tendons. Complete reversibility of changes in the mechanical properties induced by 30 days of corticotrophin treatment was found after an additional period of 30 days of saline injections. This study indicates that an increased level of plasma corticosteroids elicited by corticotrophin treatment may increase the stiffness of the connective tissue of the organism. In the aorta this results in loss of capacitive function with increased haemodynamic strain on the aortic wall.
Inhibition of bone resorption and lysosomal enzyme release from calvarial bones cultured for 24 hours: synergism between cyclic AMP analogues and phosphodiesterase inhibitors
Authors: Lerner Ulf
Published: December 2008

The effect of N6-monobutyryl adenosine 3′,5′-cyclic monophosphate (mbcAMP), N6,O2′-dibutyryl adenosine 3′,5′-cyclic monophosphate (dbcAMP), 8-bromo adenosine 3′,5′-cyclic monophosphate (8-brcAMP), adenosine 3′,5′-cyclic monophosphate (cAMP) and two phosphodiesterase (PDE) inhibitors, theophylline and 3-isobutyl-methylxanthine (IBMX) on bone resorption was studied in an organ culture system for 24 h using half calvaria from 6–7 day old mice. The parameters studied were: the release of calcium (Ca2+), inorganic phosphate (Pi), β-glucuronidase, β-galactosidase, lactate dehydrogenase (LDH), and 45Ca from the bones to the medium. With dbcAMP, in concentrations between 5 × 10−5m and 2.5 × 10−4m, and with 8-brcAMP, in concentrations between 10−5m and 5 × 10−5m, a dose-dependent inhibitory effect on the spontaneous release of 45Ca from the explants was found. IBMX and theophylline in doses of 10−3m and 2.5 × 10−3m, respectively, inhibited the spontaneous mobilization of 45Ca, while hypoxanthine, which lacks PDE inhibitory capacity, did not affect the release of 45Ca. When cAMP or its analogues were combined with IBMX, a potentiated inhibitory effect on mineral mobilization and lysosomal enzyme release was seen. In contrast, adenosine 5′-monophosphate, 8-bromo adenosine 5′-monophosphate and sodium butyrate did not reduce the release of 45Ca when applied alone or combined with IBMX. PDE inhibitors combined with parathyroid hormone (PTH) resulted in a reduction of the PTH-stimulated bone resorption. The results provide further evidence that cAMP is not a mediator of the early stage of PTH-induced bone resorption, but on the contrary inhibits mineral mobilization and lysosomal enzyme release from cultured bones.
Prolactin, LH, FSH, GH and cortisol response to surgery and the effect of epidural analgesia
Authors: Hagen Claus , Brandt Mogens R. , Kehlet Henrik
Published: December 2008

The prolactin, LH, FSH, growth hormone and cortisol responses to surgical stress were studied in female patients receiving halothane (general) anaesthesia or epidural analgesia. Plasma cortisol, prolactin, and growth hormone concentrations increased during surgery, and post-operatively in patients operated under general anaesthesia, but not in patients operated during epidural analgesia. Gonadotrophin concentrations were unchanged in the general anaesthesia group until 9 h after stimulation when levels decreased slightly. In contrast plasma gonadotrophin levels decreased immediately after the administration of epidural analgesia and during the following 9 h. It is concluded that neurogenic blockade inhibits the anterior pituitary response to surgial stress.
Somatomedin A levels in serum from healthy children and from children with growth hormone deficiency or delayed puberty
Authors: Hall Kerstin , Enberg Gösta , Ritzén Martin , Svan Håkan , Fryklund Linda , Takano Kazue
Published: December 2008

Serum somatomedin A (SMA) has been determined in healthy children (n = 188) in relation to age using both a radioimmunoassay and a radioreceptor assay. The SMA levels, only 50% of adult values at birth, rise gradually with age and reach adult levels at 10 years of age. There is a significant correlation (r = 0.46, P < 0.001) between SMA determined by the two methods throughout childhood except during puberty. Immunoreactive SMA shows a marked pubertal rise in values with a peak 2 years earlier for girls than boys, which is not observed by the radioreceptor assay technique. In boys with delayed puberty the increase in immunoreactive SMA is seen first when the testes reach a size of 5 ml. Children with growth hormone deficiency (n = 30) had significantly lower levels of SMA than healthy age-matched controls. Immunoreactive SMA gives a better separation of these groups than the values obtained by radioreceptor assay.
Effect of acute hypercalcaemia on glucose tolerance and insulin release in human beings
Authors: Gedik O. , Akalin S. , Koray Zehra
Published: December 2008

Insulin secretion in response to an oral glucose challenge during acute hypercalcaemia was studied. Oral glucose tolerance tests (OGTT) were performed in 12 non-diabetic, non-obese human volunteers, aged 20–28 years. Blood samples were collected for calcium, glucose and insulin determination. The next day the same volunteers received a 4 h infusion of calcium gluconate (15 mg/kg/4 h) and were administered glucose 1 h after starting the infusion. Serum calcium, glucose and insulin concentrations were measured again.

Infusion of calcium gluconate resulted in an increase in serum calcium concentration of 5 mg/100 ml over 4 h. During these infusions no significant changes in glucose concentrations were noted. On the other hand, the total mean insulin concentration, expressed as the area under the 3 h glucose tolerance curve, and the insulin peak at 30 min were significantly increased during hypercalcaemia (P < 0.001).

These data indicate that acute hypercalcaemia does not affect carbohydrate tolerance but increases insulin secretion in human beings.
The effect of cyproterone acetate on serum lipids in normal men
Authors: Damgaard-Pedersen Finn , Føgh Marie
Published: December 2008

In a male anti-fertility study 7 volunteers received the anti-androgen cyproterone acetate (5 or 10 mg daily) orally in a paired study. A significant reduction in serum-cholesterol and LDL-cholesterol, and a significant increase in the intravenous-fat-tolerance-test (IVFTT) was observed. Thus low doses of cyproterone acetate reduced the serum testosterone concentration and some of the atherosclerotic risk factors.
Inhibition of vasopressin secretion by a met-enkephalin (FK 33-824) in humans
Authors: Brownell Judith , del Pozo Emilio , Donatsch Peter
Published: December 2008

To investigate the effect of a met-enkephalin analogue, FK 33-824, on renal handling of water, 8 subjects were given 0.5 mg im of the drug or placebo in a cross-over study. In a second trial under the same testing conditions, a 4 mg dose of naloxone iv was given to 6 subjects immediately preceding 0.5 mg FK 33-824 im. Urine and blood samples were collected at hourly intervals. Urinary vasopressin (AVP) and plasma prolactin (Prl) were assayed, and free water clearance (FWC) was calculated. Following the same protocol, a further 6 subjects received 5 IU of lysine vasopressin im 5 min preceding administration of FK 33-824.

FK 33-824 significantly (P < 0.001) increased Prl and FWC and reduced urinary concentrations of AVP (P < 0.01). Naloxone pre-treatment failed to modify significantly the latter two responses, while Prl stimulation was inhibited. Lysine vasopressin pre-treatment abolished the effect of FK 33-824 on FWC while the stimulating action on Prl was preserved.

These results indicate that in humans FK 33-824 reduces AVP secretion and that this effect is not mediated by naloxone sensitive opiate receptors.
The effect of heat exposure on blood serum levels of anterior pituitary hormones in calves, heifers and bulls
Authors: Schams D. , Stephan E. , Hooley R. D.
Published: December 2008

In four experiments male and female calves, heifers and bulls were housed in a climate chamber and exposed to two weeks of hot environmental conditions (30–35°C and 60% relative humidity (RH) during the day; 25°C and 60–70% RH during the night). The animals were subjected to milder conditions (15–18°C and 70% during the day; 12–15°C and 70% during the night) during the two week period preceding and the two weeks following heat exposure. Serum prolactin increased significantly (P < 0.01) when ambient temperature was increased and decreased after reduction of temperature. No changes could be observed for GH, TSH, LH and FSH. There was a significant (P < 0.01) sex difference in GH levels (males < females) in pre-pubertal calves but this difference was not apparent in older animals.
Effect of prolactin inhibition under heat exposure on water intake and excretion of urine, sodium and potassium in bulls
Authors: Schams D. , Stephan E. , Hooley R. D.
Published: December 2008

Six Holstein bulls were housed in a climate-chamber under constant light regimen and after two weeks of preconditioning at 15°C, 60% relative humidity RH (day) and 12°C, 60% RH (night) were subjected to two weeks of heat exposure. This involved one week at 30°C and 60% RH (day) and 25°C and 60% RH (night) and a further week at 35°C, 60% RH (day) and 30°C, 60% RH (night). Three bulls were untreated (group I) and 3 bulls were treated (group II) just before and during heat exposure with a prolactin inhibitor to study the possible physiological role of prolactin on the regulation of water, potassium and sodium.

Serum prolactin levels increased significantly (P < 0.01) in group I from the control value of 6 ng/ml to 33 and 44 ng/ml when the ambient temperature was increased (weeks 3 and 4) and then decreased to 21 and 12 ng/ml after reduction in temperature during weeks 5 and 6, respectively.

For group II prolactin values decreased under the treatment with the prolactin inhibitor to 0.5 ng/ml and remained at this level throughout the experiment. GH levels were unaffected by heat treatment or by treatment with prolactin inhibitor. There were no differences between groups I and II in respiratory rate, pulse rate and rectal temperature. Water intake increased in both groups under heat exposure but decreased significantly afterwards only in group II. Differences in urinary excretion volume and blood serum osmolality were not significant. Urinary potassium and sodium excretion were unchanged in group II but increased with heat exposure in group I. During heat exposure 2 bulls of group II lost weight despite maintaining food intake.
Role of the renin-angiotensin system in the adaptation of aldosterone biosynthesis to sodium restriction in the rat
Authors: Tarján Eva , Spät András , Balla Tamás , Székely Annamária
Published: December 2008

The purpose of the present study was to evaluate the role of the renin-angiotensin system in the secretion of aldosterone during restriction of dietary sodium intake. Rats were kept on control or low-sodium diet for one week. On the 7th morning of diet osmotic minipumps filled with the angiotensin converting enzyme inhibitor (CEI) SQ 20,881, or empty pumps, were implanted subcutaneously (sc). The rats were sacrificed 23 h later. Peripheral blood was analyzed for hormones and electrolytes. Adrenal capsular tissue (z. glomerulosa) was incubated for the determination of the conversion of [3H]corticosterone to [3H]aldosterone.

Sodium depletion had no effect on plasma sodium, but it increased potassium concentration. Infusion of CEI had no significant effect on plasma electrolytes. Plasma renin activity was increased both by sodium depletion and CEI. The mean serum aldosterone level was twelve times higher in sodium depleted animals than in controls. Aldosterone level was reduced by about 60 per cent in CEI-infused animals both on control and low-sodium diet. The conversion of corticosterone to aldosterone was significantly stimulated by sodium deprivation. This effect was also inhibited by the CEI SQ 20,881.
Ontogeny of pituitary gonadotrophin hormone activity and of testicular responsiveness to gonadotrophins in foetal rabbit
Authors: Veyssiere G. , Berger M. , Jean-Faucher Ch. , de Turckheim M. , Jean Cl.
Published: December 2008

Synthesis and secretion of T and DHT by 18, 19 and 20 day old foetal rabbit testes were measured (RIA) in an organ culture system (M199). It was demonstrated that synthesis and secretion in vitro of T and DHT were greater at 19 and 20 days than at 18 days. The T and DHT production could be stimulated by ovine LH at 19 and 20 days but not at 18 days. The pituitaries of 19 and 20 day old male and female foetuses (but not those of foetuses aged 18 days) stimulate synthesis and secretion of T by 20 day old testis. A gonadotrophic factor, active on testicular T production, is present in the pituitary gland of 19 day old foetuses of both sexes.

These findings indicate that the testicular responsiveness to LH and to the pituitary appears concomitantly with the pituitary gonadotrophic activity, between 19 and 20 days, just prior to the beginning of male sexual differentiation (20–25 days).
The value of an intravenous TRH test for the diagnosis of tumoural prolactinaemia
Authors: Assies J. , Schellekens A. P. M. , Touber J. L.
Published: December 2008

The plasma Prl response to 200 μg TRH iv was evaluated in 6 hyperprolactinaemic women without radiological evidence of a pituitary tumour (group I), in 15 hyperprolactinaemic women with dubious (group II) and in 17 normo- or hyperprolactinaemic women with clear (group III) radiological abnormalities, in 18 normoor hyperprolactinaemic men with clear radiological abnormalities (group IV), and in 4 women and 3 men with hyperprolactinaemia and sellar destruction who had been treated in the past for pituitary adenoma (group V). The responses were compared with those obtained in a control group of 83 (42 women, 41 men) normoprolactinaemic healthy individuals. The Prl response was defined as a ratio (R2): the 20 min value minus the 0 min value, divided by the 0 min value.

The median R2 values were: female controls 5.1, male controls 3.1, group I 0.1, group II 0.2, group III 0.3, group IV 0.55, group V females 0.45 and males 0.

It is concluded that 1) subjects suspected of harbouring a microprolactinoma (groups I and II) demonstrate absent or attenuated responses similar to those found in patients with definite prolactinomas and 2) a value of plasma Prl 20 min after 200 μg TRH iv greater than 3.5 times the basal level (R2 > 2.5) rules out the presence of a prolactinoma.
The clinical and biochemical features in 26 patients with prolactinoma before and after transsphenoidal microresection
Authors: Samaan Naguib A. , Elhaj George E. , Leavens Milam E. , Franklin Robert R.
Published: December 2008

Twenty-six women, 16 to 40 years of age, with amenorrhoea with or without galactorrhoea and abnormal pituitary fossa tomogram were studied before and after transsphenoidal resection of their pituitary adenomas. The immunoreactive serum prolactin (Prl) was abnormally high both before and after intravenous (iv) administration of thyrotrophin-releasing hormone (TRH) but the rise was blunted. The serum Prl level returned to normal post-operatively in 20 patients, but the subnormal rise after TRH persisted in 23 patients. The basal serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were normal before and after surgery. The peak serum level of LH after administration of the luteinizing hormone-releasing hormone (LRH) was normal but the peak FSH was significantly high before surgery (P < 0.001) and returned to normal post-operatively. Plasma oestradiol (Oe2) was significantly low compared to that after surgery (P < 0.001). Plasma testosterone (T) was significantly higher before surgery than that found in normal women (P < 0.001) and the level fell post-operatively. Plasma androstenedione (A) was higher before surgery than found in normals, but the difference was not significant (P < 0.2).

Post-operatively, 23 patients regained their normal menses. Three of these 23 patients continued to have high serum Prl but the serum Oe2 returned to normal. Sixteen of 20 patients who desired pregnancy became pregnant post-operatively. None of the patients required hormonal replacement after surgery.

These data indicate that the measurement of LH or FSH at basal and after LRH stimulation, may not be of significant prognostic importance compared with serum Prl and plasma Oe2. Regular menses and pregnancy can occur in some patients in spite of moderately high serum Prl but normal plasma Oe2 levels.

Surgical resection of prolactinoma has low morbidity with a high incidence of success resulting in return of normal menses and fertility. The persistent subnormal rise of Prl after TRH post-operatively in the majority of the patients suggests that long-term follow-up for evidence of recurrence is indicated.
Precocious and delayed puberty. Studies of FSH and LH production and metabolism
Authors: Raiti Salvatore , Maclaren Noel K. , Akesode F. A.
Published: December 2008

We measured the production rates and metabolic clearance, disappearance and excretion rates of FSH and LH as well as plasma testosterone and Δ4androstenedione in males with precocious and delayed puberty. In precocious puberty, we found modestly elevated FSH production early in puberty, reaching adult levels by midpuberty and remaining constant thereafter. LH production was low early in puberty, reached high levels at midpuberty and then fell. The plasma testosterone concentrations paralleled the changes in LH. This suggests that moderate FSH production is achieved by early puberty and adult levels are reached by midpuberty. On the other hand LH production is low early in puberty, reaches high levels by midpuberty and then falls again towards the end of puberty.

Constitutional delay in sexual development probably consists of several syndromes due either to a delay in LH production or to FSH production or to both. One patient with hypogonadotrophic hypogonadism was also studied. He showed relatively normal LH production but very low FSH production.
Urinary excretion of catecholamines in healthy subjects in relation to body growth
Authors: Parra A. , del Angel A. Ramírez , Cervantes C. , Sánchez M.
Published: December 2008

The daily urinary excretion of dopamine (DA), noradrenaline (NA) and adrenaline (A) was investigated in 43 clinically healthy males and 37 females, aged 13 days to 37.5 years. There was a progressive increase in the daily output of each catecholamine (μg/24 h) with increasing age (P < 0.025 to < 0.001), and the opposite was seen when values were expressed as μg/g creatinine (P < 0.05 to < 0.025). However, when values were expressed as μg/m2/24 h no significant differences were disclosed among the different age groups, except for a transient rise in DA excretion in the group 1.0–4.9 years. A significant linear correlation was observed between chronological age and urinary DA (r = 0.814, P < 0.05), NA (r = 0.837, P < 0.05) and A (r = 0.839, P < 0.05), and also between body weight and each one of the catecholamines (DA: r = 0.731, P < 0.05; NA: r = 0.839, P < 0.05; A: r = 0.720, P < 0.05). However, a quadratic correlation existed between height and DA (r = 0.759, P < 0.05), NA (r = 0.853, P < 0.05) and A (r = 0.814, P < 0.05). Each one of these models could explain up to 73% of the observed variability. It is suggested that: a) the most convenient form to express the daily urinary excretion of catecholamines is as μg/m2/24 h; b) the excretion of these compounds increased at a faster rate approximately after 130.0—135.0 cm of height; c) this height-related greater increase in the output of catecholamines occurs simultaneously with previously reported increases in haemoglobin and haematocrit and significant changes in plasma concentrations of thyroid hormones; d) although the mechanisms involved in these changes remain to be clarified, it is interesting to note that they occur at a time when oxygen requirements are greater consecutive to the rapid increase of lean body tissues.
Thyrotroph cell adenoma of the human pituitary gland associated with primary hypothyroidism: clinical and morphological features
Authors: Katz Michael S. , Gregerman Robert I. , Horvath Eva , Kovacs Kalman , Ezrin Calvin
Published: December 2008

The morphological features of a pituitary adenoma resected from a 39-year-old woman with hypothyroidism have been investigated. Hypothyroidism followed radioactive iodine treatment of pre-existing hyperthyroidism, presumably Graves' disease. Blood TSH was low during a euthyroid interval and was elevated above normal with the onset of hypothyroidism. The presence of a small amount of TSH was demonstrated in the tumour by radioimmunoassay. By conventional histology the tumour was a chromophobe adenoma. Some fine secretory granules stained with aldehyde thionin but were negative with PAS and contained no immunoreactive TSH. By light and electron microscopy, the tumour cells differed from thyroid deficiency cells. They were small and angular, containing numerous microtubules and small spherical secretory granules, oriented mainly along the plasma membranes. The tumour was considered to represent a thyrotroph cell adenoma, arising from protracted overstimulation secondary to chronic thyroid hormone deficiency.
Biosynthesis of 16α,17α-epoxy-oestratrienol in rat liver microsomes
Authors: Siekmann L. , Thull P. , Breuer H.
Published: December 2008

After incubation of 1,3,5(10),16-oestratetraenol, a 16-dehydrosteroid, with rat liver microsomes, 16α,17α-epoxy-oestratrienol was isolated as metabolite. The compound was detected by the use of mass fragmentography after purification of the incubation extract by thin-layer chromatography. Since the epoxide is rapidly hydrolysed by a hepatic epoxide hydratase, only very small concentrations of this metabolite were present in the incubation extract. When styrene oxide was added to the incubation mixture as inhibitor of the epoxide hydratase, the yield of the steroid epoxide increased considerably. Final identification of the oestrogen epoxide was performed by recording mass spectra and by comparison with authentic reference material.
Biosynthesis of 16α,17α-epoxy-4-androsten-3-one in rat liver microsomes
Authors: Disse B. , Siekmann L. , Breuer H.
Published: December 2008

4,16-Androstadien-3-one was incubated with the microsomal fraction of male rat liver in the presence of a NADPH generating system and oxygen. The metabolites formed were extracted from the incubation medium and purified by thin-layer chromatography (tic). Final identification was performed by combined gas liquid chromatography-mass spectrometry. Incubation of 4,16-androstadien-3-one resulted in the formation of a non-polar metabolite which proved to be 16α,17α-epoxy-4-androsten-3-one. This epoxide is a shortlived intermediate which is rapidly hydrolysed by the microsomal epoxide hydratase to 16β,17α-dihydroxy-4-androsten-3-one. In order to increase the amounts of epoxide in the incubation mixtures, styrene oxide which is a potent inhibitor of the epoxide hydratase was added. Under these conditions, up to 8% of the 16-dehydro-steroid incubated was transferred to the 16α,17α-epoxy-compound.
Testosterone and 17 OH-progesterone responses in men to 3 h LH infusions
Authors: Nankin H. R. , Lin T. , Murono E. , Osterman J. , Troen P.
Published: December 2008

LH is recognized as the Leydig cell stimulus for testosterone production. Yet earlier studies of bolus administered human pituitary LH did not result in testosterone elevations and spontaneous LH elevations infrequently cause recognizable parallel rises of testosterone in adult males. Therefore, 10 normal adult volunteers were given 3 h infusions of human pituitary LH A-3 (2 IU/kg) and sampling was continued for 3 h after the gonadotrophin was stopped. Testosterone, the precursor 17 OH-progesterone and LH were determined in blood samples. There was a mean 5.2-fold LH elevation. From a group baseline mean of 698 ng/100 ml ± 72 (± se) testosterone gradually rose and was significantly elevated at 90, 120 and 150 min (787 ± 67 P <0.03, 767 ± 60 P < 0.04, and 804 ± 69 P < 0.001, respectively). 17 OH-progesterone was determined on 9 subjects and averaged 142 ng/100 ml ± 16 before LH and gradually rose to 178 ± 18 at 120 min (P < 0.05) and then declined slightly at 150 and 180 min. Both steroids significantly declined between 180 min (end of LH infusion) and 240 min with no further significant concentration changes. The two men with the highest basal testosterone titers showed the smallest testosterone increases, but in both 17 OH-progesterone rose. In conclusion tonic LH stimulation caused mean testosterone and 17 OH-progesterone to peak at 150 min and at 120 min, respectively. Factors within the Leydig cell appear to limit increases of testosterone and 17 OH-progesterone during the first few hours of enchanced gonadotrophin stimulation.
The role of follicle stimulating hormone in testicular function of the mature rhesus monkey
Authors: Wickings E. J. , Usadel K. H. , Dathe G. , Nieschlag E.
Published: December 2008

In the rat, whilst FSH has been shown to be necessary for the initiation of spermatogenesis, this hormone does not appear to be involved in the maintenance of spermatogenesis in the mature animals. Since the role of FSH has not been conclusively established in primate species, including humans, a study based on the neutralization of FSH by passive immunization with specific FSH antibodies was initiated in adult male rhesus monkeys.

Prior to the actual study an antiserum pool was generated from 4 monkeys actively immunized with highly purified ovine FSH. In this FSH antiserum there was no evidence for the existence of LH antibodies, and the capacity of the antiserum to neutralize rhesus FSH was demonstrated by bioassay. Because of marked circannual variations in testicular functions passive immunization with FSH-antiserum was performed during the period of full testicular development in 4 other monkeys. FSH antiserum was injected for 106 days (i.e. a period covering the full duration of the total spermatogenetic process twice). Four further monkeys serving as controls were injected with normal rhesus serum for the same period. Testicular volume and histology, anti-FSH-titer, seminal parameters, serum testosterone, and LH were monitored at regular intervals.

In the passively immunized animals the testicular volume decreased by 50%, sperm counts decreased below control counts, histology revealed reduction of the tubular diameter by 40%, derangement of spermatogenesis and, on instances, tubuli with Sertoli cells only. Leydig cells appeared histologically normal, although testosterone levels in the passively immunized monkeys tended to be lower than in control animals. Values were not significantly different at the end of the observation period.

From these results it can be concluded that in contrast to the rat FSH plays a specific role in the maintenance of spermatogenesis in the mature rhesus monkey.
The effect of serum from obese and normal weight men on glucose metabolism in leucocytes
Authors: Myking Ole , Kjøsen Berit , Bassøe Hans H.
Published: December 2008

The influence of pooled serum from either obese or normal weight males on glucose metabolism in human leucocytes has been studied. Leucocytes from normal weight males were incubated with 10–90% pooled serum and either [U-14C], or [1-14C]glucose. Compared to serum from the normal weight males, serum from the obese group had a more stimulating effect on the 14CO2 and [14C]lactate production from [U-14C]glucose and on the 14CO2 production from [1-14C]glucose. The two serum pools had the same stimulating effect on the Embden-Meyerhof pathway as indicated by the formation of [14C]lactate from [1-14C]glucose. Calculations revealed that the activity in the pentose phosphate pathway was stimulated more by serum from obese, than from normal weight males. It is a possibility that increased stimulation of the pentose phosphate pathway may contribute to the development of overweight.
Effect of sulpiride on plasma prolactin levels in women with puerperal or pathological hyperprolactinaemia
Authors: Massara F. , Camanni F. , Belforte Luisa , Campagnoli C. , Novi Rosa F. , Molinatti G. M.
Published: December 2008

The effect of 100 mg im sulpiride on plasma Prl levels was studied in 10 normal females, 21 patients with galactorrhoea and normal plasma Prl, 10 women with puerperal hyperprolactinaemia and 27 patients with amenorrhoea-galactorrhoea and high plasma Prl levels.

The response to sulpiride in patients with galactorrhoea but normal Prl was slightly higher (P < 0.05) than that observed in normal women, but only if expressed in per cent.

Women with puerperal hyperprolactinaemia respond to the drug with a marked increase in Prl (mean ± sem: 563.0 ± 142.8%), even though their baseline values are already very high (mean ± sem: 133.6 ± 23.8 ng/ml).

By contrast, there is a lower or no response to sulpiride in 13 women with pituitary tumour.

The same was true in 11 patients with hyperprolactinaemia of uncertain aetiology but also 10 of these subjects presented signs suggestive of a tumour.

In the last 3 patients with pathological hyperprolactinaemia in whom a consistent Prl increase after sulpiride was observed, hyperprolactinaemia was probably not of tumourous origin.

On the basis of these results, the sulpiride test appears promising for discriminating between organic and 'functional' cases of enhanced Prl secretion.
Marathon run: effects on blood cortisol — ACTH, iodothyronines — TSH and vasopressin
Authors: Dessypris A. , Wägar G. , Fyhrquist F. , Mäkinen T. , Welin M. G. , Lamberg B.-A.
Published: December 2008

Blood cortisol, ACTH, thyroxine, triiodothyronine, reverse triiodothyronine, thyroid stimulating hormone (TSH) and vasopressin concentrations were determined in 9 runners (29–56 years old) and one 80 year old man taking part in a non-competitive Marathon in Athens, Greece on October 1976. After the run the mean concentrations of cortisol, ACTH and vasopressin showed a significant rise. The thyroid function variables and TSH did not differ from the control values. There was a significant correlation between the cortisol and ACTH levels after the race and also between their increments from the corresponding base values. A significant correlation was found between the physical fitness (as measured by indirect determination of Vo2max) and the post-race cortisol levels. One of the well trained runners with a fairly good running time had the highest post-race values for 6 of 7 hormones studied.
Changes in adenylate cyclase activity in rat pituitary after TRH and T3 injection in vivo
Authors: Brozmanová Hana , Langer Pavel , Knopp Jan , Földes Ondrej
Published: December 2008

Increased activity of adenylate cyclase in whole anterior pituitary was repeatedly found in groups of 3–6 adult male rats 5 min after iv injection of 10, 100 and 200 nmol of TRH kg−1. After the administration of 100 nmol TRH kg−1 the activity of adenylate cyclase was significantly increased at 2, 5, 10 and 30 min with a peak level at 5 min, while at 60 min the values did not differ from controls. The level of TSH in serum was significantly increased in all TRH injected groups with a peak value at 10 min, while no dose-response relationship was found at 5 min. Finally, the activity of adenylate cyclase was significantly decreased in animals injected with 20 nmol of l-triiodothyronine kg−1 180 min before sacrifice, the decrease being not overcome by 100 nmol TRH kg−1 injected 5 min before sacrifice.
Evidence for α-adrenergic receptors mediated TSH release in men
Authors: Zgliczyński Stefan , Kaniewski Marek
Published: December 2008

In order to elucidate the role of the adrenergic nervous system in the mechanism of TSH release in men the effects of α- and β-receptors blocking agents were studied in 11 healthy volunteers. Phentolamine administetred iv as a bolus injection in a dose of 10 mg, significantly lowered the TSH release in basal condition and in response to TRH stimulation. However, propranolol in a dose of 0.1 mg/kg administered in the same fashion as phentolamine had no effect on the TSH secretion. The results obtained suggest that the α-receptors of the adrenergic system are involved in the physiological mechanism which stimulates TSH release in men.
A pituitary tumour with possible ACTH and TSH hypersecretion in a patient with Addison's disease and primary hypothyroidism
Authors: Aanderud Sylvi , Bassøe Hans H.
Published: December 2008

A patient with Addison's disease, who was inadequately substituted with corticosteroids for twenty-five years, developed a pituitary tumour. The diagnosis of autoimmune thryroiditis with asymptomatic hypothyroidism was also made. ACTH and TSH plasma values were abnormally elevated. The ACTH secretion was suppressed by cortisone administered perorally. It seems possible that the pituitary enlargement is due to prolonged insufficient adrenocortical replacement therapy. The differential diagnosis and possible pathogenetic factors are discussed.
Defective cortisol binding globulin affinity in association with adrenal hyperfunction: a case report
Authors: Barragry J. M. , Mason . Stuart , Seamark D. A. , Trafford D. J. H. , Makin H. L. J.
Published: December 2008

A patient with an apparent abnormality of cortisol binding globulin (CBG) is reported. Investigations showed that while the plasma CBG binding capacity (equivalent to the plasma CBG concentration) was normal, the binding affinity was reduced by a factor of four. The significance of this observation is discussed with regard to its possible role in the development of the adrenocortical hyperfunction also seen in this patient.
The effect of chronic low-dose infusion of ACTH (1–24) on renin, renin-substrate, aldosterone and other corticosteroids in sodium replete and deplete man
Authors: Fuchs-Hammoser Regina , Schweiger Martin , Oelkers Wolfgang
Published: December 2008

Low-dose infusions of ACTH 1-24 (5 U/day) of 4 days duration were performed in 2 healthy young men on a normal sodium diet and in 2 on a low sodium diet, in order to study the mechanism of the transient effect of ACTH on aldosterone secretion described by other authors using larger doses of ACTH. Cortisol secretion was continuously stimulated by ACTH. Plasma aldosterone (P-Al) and its urinary metabolites increased during the first two days of infusion and returned to control or below control levels subsequently. Plasma renin activity (PRA) was also transiently stimulated by ACTH. Changes in PRA were not caused by changes in plasma renin substrate concentration. The correlation between PRA and P-Al (r = + 0.78; n = 52) was highly significant (P < 0.01). Plasma levels of deoxycorticosterone (DOC), 18-OH-DOC and corticosterone were also transiently stimulated in subjects on a normal sodium diet, while the stimulation was better maintained in those on a low sodium diet. The results suggest that the transient effect of low-dose ACTH infusion on aldosterone secretion may in part be mediated by changes in the renin-angiotensin-system. Changes in plasma levels of angiotensin II, which controls early and late steps in the mineralocorticoid biosynthetic pathway, may determine the extent to which chronically elevated ATCH levels stimulate the release of aldosterone and, perhaps, even the release of DOC and corticosterone. On the normal sodium diet, sodium retention and a slight fall in serum potassium levels towards the end of ACTH infusion may have contributed to the depression of aldosterone release.
Preparation of a partially desialylated human chorionic gonadotrophin (hCG) and its use for induction of ovulation after ovarian stimulation with human menopausal gonadotrophin
Authors: Crosignani P. G. , Donini P. , Lombroso G. C. , Donini S. , Caccamo A. , Trojsi L.
Published: December 2008

A method for the large scale preparation of partially desialylated human chorionic gonadotrophin suitable for human use is reported. To obtain the desired grade of desialylation and to avoid the presence of the enzyme in the modified hormone, neuraminidase coupled to Sepharose 4B was used. The preparation showed to be active in vitro (OAAD and SVW tests) and its half-life was found to be 13 min in the rat and 75 min in human beings. This desialo hCG proved to be effective in inducing ovulation in amenorrhoeic women. Among 39 induced cycles 31 ovulations and 5 pregnancies occurred.
Treatment of anorchia with oral testosterone undecanoate: pharmacodynamics and clinical effectiveness
Authors: Weil J. , Bidlingmaier F. , Butenandt O. , Sippell W. G. , Baumgartner W. , Knorr D.
Published: December 2008

The pharmacodynamics of plasma testosterone (T) and androstenedione (A) levels were studied in ten hypogonadal boys after oral administration of testosterone undecanoate (TU).

Plasma T and A levels were measured by specific radio-immunoassays.

Six hours after a single dose of 120 mg TU, there was a significant increase (P < 0.005) in plasma T and A with a median T peak level of 940 ng/100 ml.

Furthermore, twelve agonadal boys treated with a mean dose of 60 mg TU/day were examined over a period of 18–24 months. During this therapy, plasma T and A levels were significantly higher than before (P < 0.005), whereas plasma levels of LH and FSH did not decrease significantly. With the exception of one anorchic boy, all patients showed signs of sexual maturation, such as growth of pubic and axillary hair, and steady development of bone age during oral TU treatment.
Effect of beta-blockade on hormone release during hypoglycaemia in insulin-dependent diabetics
Authors: Lager Ibe , Jagenburg Rudolf , von Schenck Henning , Smith Ulf
Published: December 2008

Previous studies have shown that non-selective, but not beta1-selective, beta-blockers prolong the duration of hypoglycaemia. In order to elucidate possible mechanisms key hormones as well as alanine levels were measured following insulin-induced hypoglycaemia in 7 insulin-dependent diabetics. The subjects were treated with placebo, propranolol (a non-selective agent) or metoprolol (a beta1-selective drug) prior to the hypoglycaemia. Treatment with either beta-blocking agent led to higher levels of adrenaline, glucagon, cortisol and growth hormone during hypoglycaemia as compared to those reached on placebo. The adrenaline levels during placebo treatment in response to hypoglycaemia appeared less in these diabetics than that previously reported for non-diabetics.

The plasma alanine levels were similar and decreased following insulin administration irrespective of type of treatment.

The data show that the release of key glycogenolytic and gluconeogenic hormones is not inhibited by beta-blockers during hypoglycaemia but is instead augmented or, possibly, hormonal clearance is reduced. It is suggested that the delayed recovery in blood glucose on a non-selective beta-blocker is partly due to lack of gluconeogenic substrates such as lactate and glycerol.
Hypergonadotrophic hypogonadism with preserved fertility — A new syndrome?
Authors: Ljungberg Sten Otto , Rannevik Gunnar
Published: December 2008

It has been claimed that a follicle-stimulating hormone (FSH) level above approximately 8 μg/l indicates ovarian failure without functioning follicles in the ovaries. Exceptional cases with elevated FSH levels and a preserved follicular apparatus in the ovaries have been published. But in none of these cases has pregnancy been reported.

This paper presents a case, which, to the best of our knowledge, is the first case in which pregnancy occurred in a patient with persistent hypergonadotrophic hypogonadism and a histologically verified normal number of primordial ovarian follicles.

The finding of menopausal levels of plasma FSH is not sufficient by itself to exclude the existence of functioning follicles in the ovaries in an amenorrhoeic patient.
Desensitization of the cyclic AMP system in rat corpora lutea. Comparison between the effects of hCG and LH
Authors: Khan M. Iqbal , Rosberg Sten , Bergh Christina , Ahrén Kurt
Published: December 2008

The changes in hormonal responsiveness of corpora lutea produced by a single injection of hCG or ovine LH were studied in PMSG-treated immature rats with well-characterized corpora lutea of different ages. The hormonal response was measured as LH-stimulated accumulation of cyclic AMP in isolated, whole corpora lutea and, in some experiments, as LH stimulated luteal adenylate cyclase activity. Injection of hCG produced a complete desensitization (refractoriness) of very long duration (4–5 days) as has earlier been found in rats with heavily luteinized ovaries, while the injection of LH in equivalent doses, produced only a partial desensitization of much shorter duration (12–48 h). Morphological observations, after injection of trypan blue to a small number of the rats, showed that follicular growth, ovulation and formation of new corpora lutea could occur after both hCG and LH. The possibility that the corpora lutea which started to respond to LH stimulation 5–7 days after the hCG injection were not the ones originally desensitized by hCG but new corpora lutea, is discussed. The very rapid recovery of the LH sensitivity after desensitization with LH, can, however, not be explained in the same way. It represents a true reversal to the 'normal' hormonal sensitivity of the cells originally desensitized. The marked difference between hCG and LH in these desensitizing experiments is discussed in relation to earlier known differences between these two gonadotrophins, e.g. in binding properties to ovarian receptors and in rate of metabolism in the body.
Bromocriptine treatment during early human pregnancy: effect on the levels of prolactin, sex steroids and placental lactogen
Authors: Ylikorkala O. , Kivinen S. , Rönnberg L.
Published: December 2008

To elucidate the role of prolactin (Prl) in the endocrinology of early human pregnancy, 28 healthy women were given 5.0–7.5 mg of bromocriptine daily for two weeks between weeks 6–9 of normal gestation. Plasma Prl, oestradiol-17β (Oe2), progesterone (P), testosterone (T) and human placental lactogen (hPL) were measured before, and one and two weeks after the start of bromocriptine, and they were compared with those in 22 control women who were followed similarly but without bromocriptine treatment. Bromocriptine treatment induced a significant Prl depression at one week (7.3 ± 4.3 ng/ml vs 23.7 ± 11.4 ng/ml) and two weeks (5.3 ± 2.5 ng/ml vs 31.9 ± 16.4 ng/ml). Oe2, P. T and hPL levels, however, showed no significant differences between the groups. Two women undergoing bromocriptine treatment (7.1%) and one control woman (4.5%) experienced spontaneous incomplete abortion during the study period, but these three already had a low Oe2 level and a low/or undetectable hPL level at the beginning of the study. It is obvious that neither maternal 'hypoprolactinaemia' nor bromocriptine during early human pregnancy interfere with the normal progress of pregnancy or with the normal synthesis of sex steroids and hPL at this time.
Linear modulation of serum thyrotrophin by thyroid hormone treatment in hypothyroidism
Authors: Pekary A. Eugene , Hershman Jerome M. , Sawin Clark T.
Published: December 2008

Basal serum TSH and the peak TSH response to a 500 μg TRH bolus were measured in 57 euthyroid and in 29 hypothyroid subjects either receiving graded thyroid hormone replacement or acutely removed from full replacement therapy. Serum TSH, total T4 and T3 were determined by sensitive radioimmunoassay methods. The peak versus basal TSH data for hypothyroid patients were linear within individuals. The regression slope of the peak versus basal TSH data for all hypothyroid subjects did not differ significantly from the corresponding slope for all euthyroid subjects. Basal and peak TSH versus T3 and T4 data for hypothyroid patients were also linear within each individual. Moreover, the regression of the basal TSH values averaged over the non-replacement to full replacement state against the TSH versus T3 slope had a significant negative correlation. This trend leads to an array of regression lines which average to the familiar hyperbolic relationship between thyrotrophin and thyroid hormone levels in man.
Serum levels of insulin-like growth factor (IGF) and its carrier protein in various metabolic disorders
Authors: Zapf Jürgen , Morell Beat , Walter Helmut , Laron Zvi , Froesch E. Rudolf
Published: December 2008

The levels of insulin-like growth factors (IGF), two somatomedin-like polypeptides of human serum and of their carrier protein were determined in sera of patients with various metabolic disorders. IGF was measured by 4 different methods (fat pad and fat cell assay and competitive protein binding assay measuring total IGF, and a radioimmunoassay for IGF I) after extraction by acidic gel filtration on Sephadex G-50. This procedure is necessary to separate IGF from the carrier protein, which interferes with all of these assays.

1) In normal serum, immunoreactive IGF I accounts for one third of total IGF determined by the fat pad assay, but only for one fifth to one sixth of immunoreactive IGF I + II.

2) In acromegalics total IGF was increased 1.5- (protein binding and fat cell assay) to 2-fold (fat pad assay), but the increase was solely due to immunoreactive IGF I, which was ∼ 5-times above normal. The IGF binding activity was not elevated. Total IGF and IGF binding were decreased in hypopituitarism, Laron-type dwarfism and in liver cirrhosis. Immunoreactive IGF I was more drastically reduced in these diseases than total IGF. Apparently, only IGF I is under growth hormone control. The liver seems to be involved in the production of IGF.

3) No elevation of total IGF was found in patients with extrapancreatic tumour hypoglycaemia, but IGF binding was reduced. Immunoreactive IGF I was decreased in 5 of 10 patients. These results suggest that tumour hypoglycaemia in our patients is unlikely to be caused by increased IGF levels.

4) In patients with hyperprolactinaemia neither total IGF nor immunoreactive IGF I were elevated, and IGF binding was unchanged.

5) In newly detected insulin-deficient juvenile diabetics total IGF and immunoreactive IGF I levels were within the normal range, although the variation was greater than in normal subjects. However, IGF binding was markedly decreased.