bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE EFFECT OF EPINEPHRINE AND ISOPROTERENOL ON INSULIN SECRETION AND GLUCOSE UTILIZATION IN ISOLATED ISLETS OF LANGERHANS FROM MICE
Authors: Hermann Leif Sparre , Deckert Torsten 
Published: December 2008

ABSTRACT
The effect of epinephrine and isoproterenol in different concentrations and adrenergic blocking agents on glucose induced insulin secretion and glucose utilization was studied in isolated islets of Langerhans from mice. Epinephrine in physiological concentrations significantly inhibited the glucose induced insulin secretion. This effect was not mediated by a change in glucose utilization but involved α-adrenergic stimulation. Isoproterenol significantly stimulated the glucose induced insulin secretion but had no effect on glucose utilization. β-adrenergic stimulation by isoproterenol at low glucose concentration was not sufficient to stimulate insulin secretion. The results are discussed in relation to current theories on the mechanism of glucose induced insulin secretion.
RELATIONSHIP BETWEEN FOETAL CORTICOSTEROIDS, MATERNAL PROGESTERONE AND PARTURITION IN THE RAT
Authors: Martin C. E. , Cake M. H. , Hartmann P. E. , Cook I. F. 
Published: December 2008

ABSTRACT
The concentration of total corticosteroids, corticosteroid binding globulin (CBG) and progesterone were determined in maternal and foetal/neonatal plasma from rats on days 5, 4, 3, 2, 1 before birth and days 0, 1, and 4 after birth. In addition free corticosteroids and adrenal weight/unit body weight were measured on the foetuses/neonates and the foetuses, respectively. Although the concentration of maternal total corticosteroids and CBG ranged from 53.0 ± 12.5 to 31.0 ± 13.1 μg/100 ml (x̄ ± sem) and 26.6 ± 2.2 to 45.1 ± 0.9 μg corticosteroid bound/100 ml plasma, respectively, the changes in the concentration of these constituents were not related to the initiation of either parturition or lactation. The concentration of total corticosteroids in foetal plasma increased significanly (P < 0.05) from day 5 (14.6 μg/100 ml) to reach peak concentrations (44.9 μg/100 ml) on day 3 before birth and then decreased to low levels (7.7 μg/100 ml) at birth.
The pattern of change in foetal adrenal weight/unit body weight closely followed the pattern of change in the concentration of total corticosteroids in foetal plasma during the last 5 days of gestation. There was a significant (P < 0.05) daily decrease in the concentration of CBG in the foetuses from 4 days before until 1 day before birth, which resulted in a significant (P < 0.01) increase from 3.08 to 5.94 μg/100 ml of free corticosteroids in the foetal plasma between day 2 and day 1 before birth, respectively. This peak corresponded with a significant fall (P < 0.02) in the maternal progesterone (measured by protein binding assay) from 2.57 μg/100 ml to 0.62 μg/100 ml between day 2 and day 1 before birth. Foetal progesterone (measured by radioimmunoassay) showed the same changes as maternal progesterone but was between 25–50 % of that in maternal plasma. These findings suggest that the changes in foetal free corticosteroids and maternal progesterone are important in the initiation of parturition in the rat.
DIURNAL RHYTHM OF 5αANDROST-16-EN-3-ONE AND TESTOSTERONE IN PERIPHERAL PLASMA OF BOARS
Authors: Claus R. , Giménez T. 
Published: December 2008

ABSTRACT
Testosterone and the boar taint steroid 5α-androst-16-en-3-one were determined radioimmunologically in peripheral plasma of 3 boars. A modified extraction procedure for the latter compound was established and its reliability confirmed. Samples of plasma were taken every 30 min during three 48 h periods.
Diurnal rhythms of both steroids were found with maximum values (concentrations > mean + 2 sd) occurring twice daily in the afternoon and after midnight. Corresponding nadirs (concentrations < mean − 2 sd) were found in the early evening and in the morning till around noon. The variations in testosterone were more smooth than those of 5α-androst-16-en-3-one. It is likely that clear cut diurnal rhythms are discernible because of the low base values.
SECRETION OF THYROXINE, 3,5,3′-TRIIODOTHYRONINE AND 3,3′5′-TRIIODOTHYRONINE IN EUTHYROID MAN
Authors: Westgren U. , Melander A. , Ingemansson S. , Burger A. , Tibblin S. , Wa°hlin E. 
Published: December 2008

ABSTRACT
The secretion of iodothyronines from the normal human thyroid gland was assessed by radioimmunoassay analyses of the concentrations of thyroxine (T4), 3,5,3′-triiodothyronine (T3) and 3,3′,5′-triiodothyronine (reverse T3, rT3) in thyroid venous and peripheral venous blood. The subjects studied were euthyroid patients undergoing parathyroid surgery. Measurements were carried out both under apparently normal conditions, following peroral T3 pre-treatment, and before and after acute administration of TSH into a thyroid artery. In the control subjects, significant gradients between thyroid venous and peripheral venous concentrations were recorded both for T4, T3 and rT3, suggesting that all three iodothyronines are secreted by the normal human thyroid. T3 pre-treatment seemed to reduce this secretion, and acute administration of TSH promoted rapid, marked, and concomitant increments in the thyroid venous concentrations of all three iodothyronines. Hence, it appears that not only T4 but also T3 and rT3 are secreted by the normal human thyroid gland, and that TSH stimulates the secretion of all three iodothyronines. On the other hand, calculations of the relative secretion rates yielded the relation T4:T3:rT3 as 85:9:1. This indicates that, in euthyroid subjects, most of T3, and almost all of rT3, is produced by extrathyroidal conversion of T4 and not by direct thyroidal secretion.
BONE MINERALIZATION AND BONE MINERAL CONTENT IN PRIMARY HYPERPARATHYROIDISM
Authors: Tougaard Lars , Hau Christian , Rødbro Paul , Ditzel Jørn 
Published: December 2008

ABSTRACT
The degree of bone mineralization and the bone mineral content (BMC) was evaluated in 6 patients with primary hyperparathyroidism. The degree of bone mineralization was estimated as the phosphorus/hydroxyproline ratio (P/Hypro) in bone biopsies; BMC was estimated by photon absorptiometry on both forearms. The mean values of both parameters were significantly lower than normal (P < 0.001 for P/Hypro; P < 0.02 for BMC). As no significant correlation was found between P/Hypro and BMC in hyperparathyroidism, the findings of low values of P/Hypro and of BMC in patients with elevated serum calcium point to primary hyperparathyroidism.
STUDIES ON THE PATTERN OF CIRCULATING STEROIDS IN THE NORMAL MENSTRUAL CYCLE
Authors: Aedo A. R. , Nuñez M. , Landgren B.-M. , Cekan S. Z. , Diczfalusy E. 
Published: December 2008

ABSTRACT
Circadian variations of the plasma levels of dehydroepiandrosterone, 17-hydroxypregnenolone, pregnenolone and testosterone were investigated by radioimmunoassay in 10 normally menstruating women during the periovulatory period. In seven of the subjects it was also possible to estimate androstenedione and dihydrotestosterone levels. Blood was withdrawn continuously over a period of 48 h at a rate of 4 ml/h by means of a non-thrombogenic pump. The circadian rhythm was studied during 13 3-hour sampling periods (39 h) which were identical in all subjects.
Dehydroepiandrosterone, 17-hydroxypregnenolone and pregnenolone showed a marked circadian rhythm with highest mean levels in the morning between 06.00 and 09.00 h and lowest mean levels during the night between 21.00 and 24.00 h. The peak levels of individual subjects coincided completely with the highest mean levels in the case of dehydroepiandrosterone, in 9 out of 10 cases with regard to 17-hydroxypregnenolone and in 8 of 10 cases as far as pregnenolone levels were concerned. The lowest individual levels were more dispersed around the means than were the individual peaks. The difference between the highest (morning hours: 06.00–09.00) and lowest (evening hours: 21.00–24.00) geometeric mean values was 404% for 17-hydroxypregnenolone, 163 % for dehydroepiandrosterone and 71 % for pregnenolone.
The mean testosterone levels also exhibited an elevation between 06.00 and 09.00 h which was significant (P < 0.05). However, the individual peak values were scattered from 21.00 h of the first day to 18.00 h of the second day. The mean concentrations of androstenedione showed a significant increase between 06.00 and 18.00 h. The individual peaks were widely dispersed. Hence a uniform circadian rhythm correlated to the levels of the Δl5-steroids mentioned above could not be demonstrated in the case of testosterone and androstenedione.
An analysis of variance indicated no significant differences between sampling periods as far as dihydrotestosterone levels were concerned.
The extent and regularity of the circadian variation in the plasma levels of the Δl5-steroids studied makes it mandatory to standardize very carefully the exact time of blood withdrawal in any longitudinal study. In view of the sharp changes in the plasma levels during the morning hours, it is suggested that sampling during the afternoon period may provide more constant values.
CORTISOL AND CORTICOSTERONE PRODUCTIONS OF ISOLATED ADRENAL CELLS IN NEONATAL RABBITS
Authors: Hirose Taeko 
Published: December 2008

ABSTRACT
Isolated adrenal cells of rabbits aged from 0 h to day 40 after birth were incubated for 2 h in the presence of ACTH. Thin-layer chromatography and the fluorimetric method were used to evaluate the products of these adrenal cells separately for cortisol and corticosterone.
Cortisol production by adrenal cells in response to ACTH (0.1 mU) was found to be highest between 0 and 8 h after birth (0.522 ± 0.049 μg/105 cells; mean ± sem). A decrease was observed at 9–20 h and this was further followed by a steady decrease up to day 35–40. Corticosterone production was 0.206 ± 0.042 μg/105 cells between 0 and 8 h after birth. Subsequently, this level was evenly maintained up to day 12–14, but it tended to increase on day 35–40. The level of cortisol production was significantly higher than that of corticosterone production at 0–20 h after birth, while the former was significantly lower than the latter from day 12–14 onwards. The ratio of corticosterone to total corticosteroids (cortisol + corticosterone) was very low (0.28 ± 0.04) at 0–8 h after birth, but showed a progressive rise up to day 35–40, when it was 0.95 ± 0.01. The results of the present study show that cortisol is the pre-dominant product of the adrenal cells in rabbits during early post-natal life.
SERUM PROLACTIN IN PATIENTS WITH "FUNCTIONLESS" CHROMOPHOBE ADENOMAS BEFORE AND AFTER THERAPY
Authors: Samaan N. A. , Leavens M. E. , Jesse J. H. 
Published: December 2008

ABSTRACT
The immunoreactive serum human prolactin (PRL) level was measured before and after intravenous administration of 500 μg of thyrotrophinreleasing hormone (TRH) in 11 patients with "functionless" chromophobe adenomas before and after surgery and after radiotherapy in 6 of these patients. The results were compared to other pituitary function tests. Two of the patients studied had recurrent disease after previous pituitary surgery and radiotherapy.
Five patients had pituitary surgery through the transfrontal route, while 6 had adenoma removal via the transnasal transsphenoidal route.
Before surgery, the serum PRL concentration was abnormally high in 4 patients, before and after TRH administration. It was normal in 6 and subnormal in 1 patient who had had previous therapy. Two of the patients studied showed high serum thyroid-stimulating hormone (TSH) levels in the presence of low serum T3 and T4 suggesting primary hypothyroidism with a secondary TSH-producing pituitary tumour.
After surgery all patients showed a significant decrease of the serum PRL level. This contrasts with more variable results in the measurements of other pituitary hormones. Post-operative radiotherapy produced no significant additional change in serum PRL levels in 5 of the 6 patients measured 6 months to 4 years after radiotherapy. Five of the 6 patients who had adenoma removed via the transsphenoidal route required no cortisol replacement and 4 remained euthyroid, whereas all 5 patients after transfrontal surgery required both cortisol and thyroid hormone replacement.
These results indicate: (1) that measurement of serum PRL levels at basal and after TRH administration in patients with "functionless" chromophobe adenomas before and after treatment may be the best index for evaluating the effect of therapy; (2) that adenoma removal may be followed by preservation of normal pituitary function, but this is more likely to occur if the transsphenoidal approach is used; and (3) that primary thyroid insufficiency may be associated with a pituitary adenoma.
BIOLOGICAL ACTIVITIES OF ACTH-ANALOGUES VARIED IN THE ACTIVE SITE
Authors: van Nispen Johannes W. , Tesser Godefridus I. , Barthe Pierre L. , Maier René , Schenkel-Hulliger Lotte 
Published: December 2008

ABSTRACT
The steroidogenic and lipolytic activities of corticotrophin-(1-24)-tetracosapeptide and [Lys17,18]corticotrophin-(1-18)-octadecapeptide amide were compared with those of corresponding analogues substituted in position 8 with norarginine and homoarginine, and in position 9 with phenylalanine and pentamethylphenylalanine. The norarginine containing analogues demonstrated a rewarding activity, although they were generally somewhat less active than the homoarginine containing compounds. This confirms the previous conclusions concerning the indispensability of arginine as a guanidinium derivate. The analogues in which phenylalanine was a substitute for tryptophan, constituted partial agonists with a low activity in steroidogenesis and lipolysis but a rather high melanophore stimulating activity. Insertion of the permethylated derivative of phenylalanine in this position, which ensures the presence of an aminoacyl residue with the full electron donor properties of tryptophan, destroyed the low steroidogenic and lipolytic activity, but increased the MSH-activity about 2-fold.
STIMULATION OF LONGITUDINAL BONE GROWTH BY HYPOPHYSEAL HORMONES IN THE HYPOPHYSECTOMIZED RAT
Authors: Thorngren K.-G. , Hansson L. I. 
Published: December 2008

ABSTRACT
The stimulating effect of different pituitary hormones on longitudinal bone growth was determined with tetracycline as intravital marker in hypophysectomized rats. Growth hormone was found to be the most effective growth stimulating pituitary hormone. At considerably higher doses, thyrotrophic hormone (TSH) and prolactin also showed growth stimulating activity. TSH exerts its effect via the production of thyroxine, whereas the growth stimulation by prolactin seems to be a direct effect of this hormone, similar to the effect of growth hormone. The LH, FSH, ACTH, MSH, vasopressin and oxytocin preparations did not stimulate longitudinal bone growth.
OUTCOME OF LONG-TERM ANTITHYROID TREATMENT OF GRAVES' DISEASE IN RELATION TO IODINE INTAKE
Authors: Lumholtz I. B. , Poulsen D. Loldrup , Siersbœk-Nielsen K. , Friis Th. , Rogowski P. , Kirkegaard C. , Hansen J. Mølholm 
Published: December 2008

ABSTRACT
Seventy-seven patients with Graves' disease, with an average of 56 years of age were treated with carbimazole in the period 1968–1975. The duration of therapy was on an average, 17.9 months and the follow-up on an average, 28.5 months. Remission was found only in 32 % of the patients. Data on the urinary iodine excretion from a total of 127 euthyroid controls and 15 patients with Graves' disease living in the same area were collected during the periods: 1962–1964, 1965–1968, 1971–1973 and 1972–1974. No significant difference was found in the urinary iodine excretion in the period 1962–1973 and no significant difference was found in the urinary iodine excretion between the patients with Graves' disease and the euthyroid controls. Our data demonstrate a high relapse rate following long-term treatment with anti-thyroid drugs in an area with relative low iodine intake.
DECREASED PARATHYROID FUNCTION IN HYPERTHYROIDISM: INTERRELATIONSHIPS BETWEEN SERUM PARATHYROID HORMONE, CALCIUM-PHOSPHORUS METABOLISM AND THYROID FUNCTION
Authors: Mosekilde Leif , Christensen Merete Sanvig 
Published: December 2008

ABSTRACT
Serum immunoreactive parathyroid hormone (S-iPTH) was measured together with serum and urinary calcium and phosphorus in 45 hyperthyroid patients in order to assess parathyroid function. Serum calcium and phosphorus were increased and positively correlated to the degree of hyperthyroidism. The prevalence of hypercalcaemia was 51.1 % using serum calcium values corrected for individual variations in serum albumin concentration compared to 15.6% using the uncorrected calcium values. S-iPTH was decreased and inversely correlated to serum calcium (corrected). Subnormal levels of S-iPTH were found in 28.9 % of the patients. The urinary excretion of calcium and phosphorus was increased and positively correlated to the degree of hyperthyroidism. The tubular reabsorption of calcium (TRCa %) was decreased, positively correlated to S-iPTH and inversely correlated to serum calcium. Increased mobilisation of bone mineral in hyperthyroidism is suggested mainly to be responsible for the elevated serum levels and increased urinary excretion of calcium and phosphorus and for the decreased parathyroid function.
VASOACTIVE INTESTINAL PEPTIDE (VIP): VARIATION OF THE JEJUNO-ILEAL CONTENT IN THE DEVELOPING RAT AS MEASURED BY RADIORECEPTORASSAY
Authors: Laburthe M. , Bataille D. , Rosselin G. 
Published: December 2008

ABSTRACT
This study was undertaken to investigate the variations of the Vasoactive Intestinal Peptide (VIP) content of rat jejuno-ileum (JI) with age. VIP was measured by its ability to inhibit competitively the binding of [125I]pork VIP (pVIP) to rat liver plasma membranes. The radio receptor assay was sensitive to 0.5 ng/ml. VIP fragments 1–6, 14–28 and 18–28 exhibited no cross reaction with [125I]pVIP. Glucagon had no effect and secretin was about 100 times less effective than pVIP. Rat VIP was extracted from JI by 0.5 m acetic acid and partially purified by adsorption on silicate. The effect of JI extracts in inhibiting the binding of [125I]pVIP paralleled that of pVIP used as standard. The VIP content of JI showed a 340-fold increase between day 21 post coitum (p.c.): 41 ± 4 ng/JI and day 63 post partum (p. p.): 14 110 ± 954 ng/JI. On a gut weight basis, VIP increased slightly from day 21 p. c. (591 ± 51 ng/g of JI) to day 14 p. p. (906 ± 109 ng/g of JI) and then increased more sharply (day 21 p. p.: 1508 ± 222 ng/g of JI) until day 63 p. p. (2672 ± 207 ng/g of JI). The VIP content seemed to reach a plateau after 2 months. A similar pattern was observed when the results were expressed per mg of JI protein. It is speculated that the rise in VIP content is related to the role of this peptide in the regulation of the gastro-intestinal function and/or the distribution of fuels in the organism.
SERUM CORTISOL APPEARANCE-DISAPPEARANCE IN ADRENAL INSUFFICIENCY AFTER ORAL CORTISONE ACETATE
Authors: Barbato Anthony L. , Landau Richard L. 
Published: December 2008

ABSTRACT
Six patients with long-standing idiopathic primary adrenal insufficiency were given 25 mg of cortisone acetate orally on two occasions. Circulating serum cortisol levels were determined hourly for five hours after ingestion. Two patients were additionally studied with an oral dose of 20 mg of cortisol. Marked patient to patient variation in peak hormone and in fifth hour hormone levels was observed. Both values were lowest in the two chronically symptomatic patients who had been maintained on empiric glucocorticoid replacement. Specific information on blood cortisol levels in treated Addisonian individuals has not been previously reported.
STUDIES ON THE PATTERN OF CIRCULATING STEROIDS IN THE NORMAL MENSTRUAL CYCLE
Authors: Landgren B.-M. , Aedo A.-R. , Nuñez M. , Cekan S. Z. , Diczfalusy E. 
Published: December 2008

ABSTRACT
By the use of a non-thrombogenic pump, blood was withdrawn continuously at a rate of 4.0 ml/h over a period of 48 h from 10 normally menstruating women during various phases of the peri-ovulatory period and the integrated levels of oestradiol, oestrone, 17-hydroxyprogesterone, progesterone, 20α-dihydroprogesterone and biologically active luteinizing hormone (LH) were estimated in 3-hourly plasma collections.
The first significant change detected two days prior to the LH surge (day LH-2) in one subject studied during this period was a continuous parallel rise in oestradiol and oestrone levels, which occurred in the absence of any simultaneous change in LH and 17-hydroxyprogesterone levels.
Marked fluctuations followed by a sudden drop in oestradiol levels were observed in another woman during the day preceding the LH peak (day LH-1). These changes were not associated with similar alterations in oestrone levels. The marked drop in oestradiol coincided with the beginning of a simultaneous major rise in LH and 17-hydroxyprogesterone levels followed some 6 to 9 h later by a small but significant increase in progesterone levels.
The period of the LH surge (day LH) was studied in 3 women. This period was characterised by a constant decline in oestradiol levels in the presence of unchanged oestrone values. The decrease in oestradiol levels preceded the LH peak by at least 12 h. The LH peak was biphasic in all subjects; both the ascending and descending limbs of it were significantly correlated to similarly changing levels of 17-hydroxyprogesterone. The increase in these two hormones preceded that in progesterone levels, which occurred later, at the time of the steepest rise in LH levels. The findings of the subsequent day (day LH+1) were characterised in two subjects by a parallel decrease in plasma oestradiol, LH and 17-hydroxyprogesterone levels, until a plateau was reached. This plateau coincided with a new rise in progesterone and 20α-dihydroprogesterone levels.
The hormonal profile observed two days following the LH surge (day LH + 2) in 3 women was similar to that of the preceding day, with the exception of a beginning new rise in 17-hydroxyprogesterone levels by the end of day LH + 2. This second rise in 17-hydroxyprogesterone paralleled that in progesterone and 20α-dihydroprogesterone levels and occurred in the presence of decreasing levels of LH.
The data reported strongly suggest that different control mechanisms are involved in the regulation of ovarian steroid secretion during the various phases of the peri-ovulatory period.
FOETAL AND MATERNAL HORMONAL CHANGES PRECEDING NORMAL BOVINE PARTURITION
Authors: Hunter J. T. , Fairclough R. J. , Peterson A. J. , Welch R. A. S. 
Published: December 2008

ABSTRACT
Successful chronic cannulation of the foetal posterior vena cava and maternal utero-ovarian and jugular veins in five Jersey cows between days 240 and 260 of gestation enabled changes in plasma hormone levels preceding calving to be monitored. All cows delivered live calves within the expected range of gestation for the breed.
Corticosteroids were assayed by competitive protein-binding, and prostaglandin F, progesterone, oestrone and oestradiol-17β by radioimmunoassay. Foetal corticosteroids rose slowly from 5.0 ± 0.7 ng/ml at 20 days to 9.3 ± 3.0 ng/ml at 10 days before term, then progressively increased to a mean of 74 ng/ml at calving. Maternal levels remained relatively constant at 5 to 15 ng/ml, though higher concentrations occurred following surgery. Foetal oestrone and oestradiol-17β concentrations were both less than 50 pg/ml and showed little change toward term. The maternal uteroovarian oestrogens increased slowly from 20 to 10 days pre-partum and then rose more rapidly reaching peak levels (2.9 ± 0.6 ng/ml for oestrone and 1.4 ± 0.3 ng/ml for oestradiol-17β) 1 to 4 days before delivery. Maternal progesterone concentrations fell towards term, with a rapid decrease over the last 36–48 h. Prostaglandin F levels showed little change until 36–48 h before calving when they gradually increased until the last 24 h where was a dramatic rise, reaching peak levels (5.7 ± 0.6 ng/ml) during labour.