bluuebunny/crossref_metadata_2025 huggingface dataset:
SPECIFIC RECEPTORS FOR PROLACTIN IN THE OVARY
Authors: Saito Tokuko , Saxena Brij B.
Published: December 2008

A role of prolactin (PRL) in ovarian function has been suggested in several species, but not unequivocally established except in the rat. We, therefore, examined the presence of specific receptor for PRL in ovaries of rat, cow, and human. Human PRL (hPRL) labelled with 125I by the lactoperoxidase method was shown to be capable of specific binding to rat mammary tissue homogenate. Human, cow, and rat ovarian homogenates and/or partially purified plasma membranes were also shown to specifically bind 125I-hPRL. Binding was a saturable phenomenon and was dependent on receptor protein concentration. Optimal binding was observed at pH 7.0 and at 37°C. Binding was reversibly inhibited by exposure of membranes to pH 10.0 and irreversibly destroyed by exposure to pH 3.0. Bound 125I-hPRL was displaceable by unlabelled human, ovine, and bovine PRL but not by FSH or LH. However, human chorionic somatomammotrophin (hCS) and hGH showed some competition with 125I-hPRL. Number of binding sites/mg protein was lowest (0.8 × 10−12 m) during metoestrus and increased during dioestrus (11 × 10−12 m) reaching the maximum number at pro-oestrus (24.6 × 10−12 m). These results demonstrate that presence of specific PRL receptor in the ovaries and are consistent with a role of PRL at the ovarian level.
CRITICAL ANALYSIS OF METHODS FOR ESTIMATING PRODUCTION RATES OF FSH
Authors: Raiti Salvatore , Blizzard Robert M. , Penny Robert , Migeon Claude J.
Published: December 2008

The urinary excretion method and the constant infusion technique were used to estimate hFSH production rates (PR) in three normal men (aged 25–40 years). Both studies were also done in a hypophysectomized nine year old boy. The PR of hFSH in the urinary excretion studies ranged from 20.0 to 45.7 IU/24 h, whereas the constant infusion studies yielded PR's of 68.7 to 107.8 IU/24 h. Possible reasons for the discrepancy of the results obtained by the two methods are discussed. In the hypophysectomized patient, the metabolic clearance rate (MCR) of infused hFSH was much lower (4.3 ml/min) than in the normal adults (7.8 to 12.0 ml/min) and was not affected by the dose of hFSH given.
CONDITIONS INFLUENCING THE DOSE-RESPONSE EFFECT OF GROWTH HORMONE ON LONGITUDINAL BONE GROWTH IN THE HYPOPHYSECTOMIZED RAT
Authors: Thorngren K.-G. , Hansson L. I.
Published: December 2008

Various factors that might influence the dose-response effect of growth hormone on the longitudinal bone growth were investigated with tetracycline as intravital marker of the bone growth in hypophysectomized rats. These are of practical importance for the bioassay of growth hormone. The growth response was found to be almost the same for subcutaneous and intraperitoneal injection, whereas the intravenous route resulted in significantly lower growth response. The administration of growth hormone in various volumes subcutaneously did not significantly influence the dose-dependent growth response. Freezing of the dissolved growth hormone or addition of NaOH to the solution had no significant effect on the growth response. Cortisone acetate 0.5 mg/kg given at hypophysectomy increased the post-operative survival somewhat, without having any post-operative depressing influence on the growth hormone-induced longitudinal bone growth. The present investigation showed that in standardized conditions the dose-dependent growth response is constant.
NORMAL RESPONSE TO THYROTROPHIN RELEASING HORMONE (TRH) IN FAMILIAL THYROXINE-BINDING GLOBULIN DEFICIENCY
Authors: Hansen E. , Kirkegaard C. , Friis Th. , Siersbæk-Nielsen K.
Published: December 2008

The response in serum thyrotrophin (TSH) to thyrotrophin releasing hormone (TRH) has been studied in 5 euthyroid patients with familial thyroxine-binding globulin (TBG) deficiency. Total serum thyroxine (T4), serum triiodothyronine (T3) and free T4 index and free T3 index were significantly and equally decreased, but in spite of these findings the serum TSH and the response to TRH was normal. The TRH test seems to be a better indicator of the euthyroid state in familial TBG deficiency than the measurement of free T4 and free T3 in serum.
ENDOCRINE FUNCTION OF THE CANINE PANCREAS
Authors: Verschoor L. , Hulsmans H. A. M. , de Gruyl J. , Westbroek D. L. , MacDicken I.
Published: December 2008

Pancreas transplantation was studied in the dog using a total duct ligated pancreas as allograft. In a group of 10 mongrel dogs the effects of longterm (6–36 months) total duct ligation on the endocrine pancreas function were studied by means of repeated intravenous glucose tolerance tests (iv-GTT). One year after total duct ligation the mean glucose assimilation coefficient (k-value) was 75%, the median insulin peak value (IPV) 63% and "total" insulin secretion in the first thirty minutes (TIS) 58 % of the pre-operative values. These levels were maintained up to three years after duct ligation.

The total duct ligated pancreas was then used as an allograft in 28 beagles in order to study the influence of DL-A (dog leucocyte-antigens) matching on the survival time of the graft. DL-A identity compared to one or two haplotype diference gave a fourfold increase in median survival time from 9 to 40 days. In a second group of 14 beagles with one haplotype difference the effect of immunosuppressive therapy was studied. The methods used (antilymphocyte serum and a combination of prednisone and azathioprine) increased the median survival time to the level seen in DL-A identity.

In conclusion the total duct ligated pancreas can be used as an insulin secreting allograft, providing rejection can be suppressed adequately.
AN ANALYSIS OF AN APPARENT SEX DIFFERENCE IN THE DESOXYRIBONUCLEIC ACID CONTENT OF RAT LIVER
Authors: Leeuwin R. S. , Visser B. J. , Meer C. v. d.
Published: December 2008

Using the extraction procedure of Schmidt & Thannhauser (1945) and the indole reaction for DNA according to Ceriotti (1952), the DNA content of female rat liver was about one and a half times that of male liver. Castration of male rats, with or without administration of testosterone propionate, had no effect on the liver DNA content. Spaying of female rats (5–6 weeks of age) caused a decrease of the liver DNA content. Substitution with oestradiol benzoate restored the amount of DNA. No significant sex difference was observed in the DNA content of either rat brain, kidney, spleen and thymus, or mouse liver. Dische's diphenylamine reaction showed no significant sex difference in the rat liver DNA content. It was concluded that rat liver may contain a substance which is controlled by oestrogens and which interferes with the indole reaction. The interfering factor is present in the protein fraction of the liver extract. The possible nature of this interfering substance is discussed.
CHANGES IN RAT ADRENAL MEDULLA FOLLOWING Δ9-TETRAHYDROCANNABINOL TREATMENT. A HISTOCHEMICAL STUDY
Authors: Biswas Bratati , Deb G. , Ghosh J. J.
Published: December 2008

The effects of acute (10 mg/kg) and chronic (10 mg/kg for 30 days) administration of delta-9-tetrahydrocannabinol (Δ9-THC) have been studied histochemically in the rat adrenal medulla, which include total catecholamines, noradrenaline, histometric measurements of adrenal medullary areas, calcium content of the medullary cells along with adenosine triphosphatase (ATPase), acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE) activities.

Acute Δ9-THC treatment reduced the total catecholamine content (including noradrenaline) of the gland, was accompanied by increased ATPase, AChE, BChE activities and increased calcium distribution in the gland. Chronic Δ9-THC treatment caused significant hypertrophy of the chromaffin tissue, with decreased total catecholamine content, although noradrenaline containing areas exhibited no notable change. The calcium content and ATPase activity were increased along with a concomitant increase in AChE and BChE activities. Although the changes in adrenal medullary enzyme activities following both acute and chronic Δ9-THC treatment are qualitatively similar, marked quantitative increase is noted in the chronically treated groups. The results indicate an increased total catecholamine releasing activity of the adrenal medulla following acute Δ9-THC treatment, while chronic Δ9-THC administration produces a preferential release of adrenaline.
HUMAN PLACENTAL LACTOGEN CONCENTRATION DURING PHYSIOLOGICAL FLUCTUATIONS OF SERUM GLUCOSE IN NORMAL PREGNANT AND GESTATIONAL DIABETIC WOMEN
Authors: Kühl C. , Gæde P. , Klebe J. G. , Pedersen J.
Published: December 2008

Oral glucose tolerance tests (OGTT) were carried out in 9 normal pregnant women and 11 non-obese gestational diabetics in late pregnancy. All samples were analysed for the content of glucose, insulin and placental lactogen hormone (HPL). Furthermore, spontaneous changes in the serum HPL concentration during a 3 h period were studied in 6 normal women in the 2nd half of pregnancy.

During OGTT only small and insignificant changes in the level of HPL were observed in both the normal subjects and the gestational diabetics. Furthermore, the mean HPL concentration curves of the normal subjects and the gestational diabetics were superimposed although the mean glucose concentration curves were significantly different. The study of spontaneous changes in HPL revealed only small and insignificant fluctuations in the serum HPL level, and the mean concentration curve resembled those obtained from the OGTT-study. It is concluded that neither the absolute serum glucose level, nor physiological fluctuations in the serum glucose concentration seemed to influence the serum concentration of HPL in this type of patients.
CIRCADIAN RHYTHM OF PLASMA CORTICOSTEROID IN ADULT FEMALE RATS: CHRONOLOGICAL SHIFTS IN ABNORMAL LIGHTING REGIMENS AND CONNECTION WITH OESTROUS CYCLE
Authors: Morimoto Yasuhiko , Oishi Tatsuo , Arisue Kazutaka , Ogawa Zensuke , Tanaka Fumiko , Yano Saburo , Yamamura Yuichi
Published: December 2008

The circadian rhythm of plasma corticosteroid (CS) levels in adult female rats was studied chronologically under the following conditions: normal light-dark (LD), inverted light-dark (DL), constant dark (DD) and constant light (LL). Animals were accustomed to LD condition for 7 days before exposure to each abnormal lighting regimen. Normal circadian rhythm established under LD condition was clearly inverted on the third day of DL regimen, and the inverted rhythm persisted thereafter under DL condition. The circadian CS rhythm persisted essentially unchanged throughout DD condition, but lost its regular periodicity showing "free running" and changed day by day under LL condition. The average CS levels over a 24 h period were higher under LL than under DD condition. Plasma CS levels in each lighting regimen exhibited diurnal variations regardless of the vaginal smear patterns of autopsied animals. Exposure of rats to LL for 21 days made the circadian CS rhythm flat, but induced persistent oestrus in only a few animals.

The data suggest that (1) an unexpectedly rapid inversion of the circadian CS rhythm occurs if animals are exposed to inverted light-dark environment; (2) constant darkness seems to be a near-natural environment for rats, and changes little of the pre-established circadian CS rhythm; (3) constant light, on the contrary, is assumed to be a stress for rats, and disrupts the circadian CS rhythm and elevates CS levels; (4) the change in circadian CS rhythm in adult female rats is not mediated by a change in gonadal function and the two conditions may not be connected directly with each other.
PROGESTERONE, 20α-DIHYDROPROGRESTERONE AND 20β-DIHYDROPROGESTERONE LEVELS IN DIFFERENT COMPARTMENTS FROM THE HUMAN FOETO-PLACENTAL UNIT
Authors: Runnebaum B. , Runnebaum H. , Stöber I. , Zander J.
Published: December 2008

The endogenous levels of progesterone, 20α-dihydroprogesterone and 20β-dihydroprogesterone in different foetal tissues, in placental tissue and in foetal blood during pregnancy (week 9–25) were determined by gas-liquid chromatography or by radioimmunoassay. The identification of these steroids in foetal tissues was based on the behaviour in paper and thin-layer chromatography, the formation of different derivatives, and the retention times in gas-liquid chromatography. For additional identification of progesterone and 20α-dihydroprogesterone a mass spectrum was obtained.

The average concentrations of progesterone (P), 20α-dihydroprogesterone (20α-DHP) and 20β-dihydroprogesterone (20β-DHP) in foetal tissues were as follows (ng/g wet weight tissue): brain, P 119.0 ± 45.5, 20α-DHP 86.9 ± 44.7 and 20β-DHP 9.7; lungs, P 257.7 ± 195.7, 20α-DHP 60.3 ± 26.4 and 20β-DHP 7.8; liver, P 103.7 ± 84.6, 20α-DHP 95.2 ± 89.8 and 20β-DHP 17.8; adrenals, P 295.7 ± 90.0 and 20α-DHP 254.5 ± 194.6; kidneys, P 214.2 ± 155.3 and 20α-DHP 76.6 ± 43.0; intestine, P 273.2 ± 166.7, 20α-DHP 77.9 ± 51.2 and 20β-DHP 8.7; residual tissues, P 246.3 ± 178.3 and 20α-DHP 54.8 ± 44.5

The average concentrations in placental tissue and in foetal plasma (week 12–18) were as follows (ng/g wet weight tissue or ng/ml plasma): placenta, P 2619. ± 2153.6 and 20α-DHP 461.0 ± 155.9; foetal plasma, P 378.7 ± 231.8 and 20α-DHP 283.0 ± 108.9

These results indicate that some foetal organs contain a high 20α-reductase activity at least during the first half of pregnancy.
THE EFFECT OF MAINTENANCE HAEMODIALYSIS AND RENAL TRANSPLANTATION ON THE PLASMA TESTOSTERONE LEVELS OF MALE PATIENTS IN CHRONIC RENAL FAILURE
Authors: Zadeh J. Alaghband , Koutsaimanis K. G. , Roberts A. P. , Curtis R. , Daly J. R.
Published: December 2008

Plasma testosterone levels were measured at the beginning of a 14 h period of haemodialysis, one hour later, midway through the period and at the end, in 18 male patients in chronic renal failure. The level fell from 8.70 ± 2.63 nmol/l at the start to 8.08 ± 3.33 nmol/l at the midpoint, and rose again to 10.12 ± 3.9 nmol/l at the end of a dialysis. All seven of the patients tested on a non-dialysis day showed similar levels at the same time. At the beginning of a 10 h dialysis period 19 other male patients showed a plasma testosterone level of 10.12 ± 3.99 nmol/l and, at the end, of 8.98 ± 4.54 nmol/l.

Over the same period the plasma corticosteroids rose from 301 ± 101 nmol/l to 483 ± 199 nmol/l. Eight male patients who had had successful renal transplantation had plasma testosterone levels of 15.08 ± 7.49 nmol/l.

It is concluded that the plasma testosterone is low in chronic renal failure, but the circadian rhythm is preserved. Treatment with maintenance haemodialysis does not itself affect the plasma testosterone level, or alter the circadian rhythm despite the procedure's being a stress. Successful renal transplantation restores the plasma testosterone to normal in most cases.
HUMAN LYMPHOCYTE BINDING AND DEIODINATION OF THYROID HORMONES IN RELATION TO THYROID FUNCTION
Authors: Holm Ann-Charlotte , Lemarchand-Béraud Thérèse , Scazziga Bianca-Rosa , Cuttelod Serge
Published: December 2008

The human lymphocyte has been investigated regarding its function as a thyroid hormone target cell. Binding and deiodination of the thyroid hormones were determined after simultaneous incubation of 131I-labelled L-thyroxine (131I-T4) and 125I-labelled L-triiodothyronine (125I-T3) with lymphocytes from healthy subjects, from hyperthyroid and primary hypothyroid patients before and after treatment.

The mean percentages of binding, 8.0 ± 0.5 (mean ± sem) for 131I-T4, and 9.7 ± 0.4 for 125I-T3 in the control group, were increased in the hyperthyroids to 10.1 ± 0.4 and 12.7 ± 0.6 respectively, and in the hypothyroids to 10.9 ± 0.7 and 12.8 ± 0.6. All elevated values returned to normal with successful treatment.

The mean percentage of deiodination, 12.0 ± 1.7 for 131I-T4, and 6.5 ± 0.9 for 125I-T3 in the control group, showed a threefold increase in the hyperthyroid patients, to 35.9 ± 3.2 and 20.2 ± 1.9 respectively and remained unaltered in the hypothyroid patients. The values of successfully treated hyperthyroid patients were normal and those of the treated hypothyroid patients below normal.

Human TSH added to the incubation medium stimulated the binding of both hormones, without influencing deiodination. Thus TSH might be active at the peripheral cellular level. This could contribute to the explanation of the increased binding by lymphocytes from primary hypothyroid patients with high serum concentrations of TSH.

A preliminary analysis of the binding characteristics revealed an equilibrium affinity constant of 1.03·1010 m−1 for T3, and of 3.97· 109 m−1 for T4, with corresponding total numbers of binding sites of 1500 and 2000 per cell.

It is concluded that, since lymphocyte activities closely reflect the thyroid function, these cells are well suited for studies on the peripheral fate of thyroid hormones and their cellular receptors.
QUANTITATIVE ANALYSIS OF PANCREATIC ISLET DEVELOPMENT AND INSULIN STORAGE IN THE FOETAL AND NEWBORN RAT
Authors: Freie H. M. P. , Pasma A. , Bouman P. R.
Published: December 2008

Pancreatic islet development and insulin storage were studied in foetal rats during the last 4 days of gestation (day 19 to 22 post-coitum (p. c.)) and in 1 and 5 days old neonatal rats. Adult female virgin rats were also studied. The percentage of granulated B-cells per islet, the degree of B-cell granulation and the islet insulin concentration rose from low levels on day 19 to adult levels on day 22 and remained stable after birth. This indicates that the qualitative maturation of the pancreatic islets as insulin producing units is completed on the last day of gestation.

The percentage of islet tissue slowly rose from 0.7 % at day 19 to 1.5 % on day 22. A further and much more rapid rise occurred during the first day of birth. At the 5th postnatal day the islets comprised 3.6 % of the pancreas versus 1.1% in adult rats. Likewise, the neonatal pancreatic insulin concentration was about 3 times higher than in the adult pancreas. The foetal pancreas as a whole showed rapid exponential growth between day 18 and 21 p. c., but a sudden decline in growth rate occurred from day 21 onward. The total mass of islet tissue, on the other hand, continued to expand at its high initial rate up to the first day after birth, whereafter this high rate also declined. The high concentration of insulin in the neonatal rat pancreas therefore appears to be due to differential growth rates of the endocrine and exocrine tissue during the last day of pregnancy and the first day after birth.
IN VITRO STUDIES ON COLLAGEN METABOLISM IN METAPHYSEAL RAT BONE
Authors: Langeland Norvald , Teig Vigdis
Published: December 2008

Oestradiol-17β has been administered to hypophysectomized/castrated and to thyro-parathyroidectomized/castrated young mature female rats. Treatment with oestradiol-17β 5 μg/day per animal, was continued for 3 weeks. Bone pieces from tibia/femur metaphyses were incubated in vitro for 3 h in order to establish the bone collagen synthesis and resorption rates. The results were compared to results from a previous study on castrated female rats with intact hypophysis, thyroid and parathyroid glands.

Bone from the thyro-parathyroidectomized/castrated rats treated with oestradiol-17β had a significantly reduced collagen resorption rate in vitro as compared to their paired controls. This is a result consistent with that of castrated female rats with intact thyroid and parathyroid glands treated with oestradiol.

Oestradiol-17β had no detectable effect upon collagen metabolism in the hypophysectomized/castrated rats.

It is concluded that the effect of oestradiol on bone resorption is not exerted via the parathyroid glands or parathyroid hormone. The possibility that oestrogens may act on bone via the hypophysis is discussed.
SUPPRESSIVE EFFECT OF L-DOPA ON HUMAN PROLACTIN RELEASE DURING SLEEP
Authors: Chihara Kazuo , Kato Yuzuru , Maeda Kiyoshi , Ohgo Shozo , Imura Hiroo
Published: December 2008

Immunoreactive plasma human prolactin (HPr) and human growth hormone (HGH) concentrations were measured in six normal young men with polygraphic sleep monitoring during normal sleep and during sleep in which 1-dihydroxyphenylalanine (1-DOPA) was infused intravenously at a rate of 0.8 to 1.0 mg/min. The intravenous infusion of 1-DOPA significantly suppressed the episodic release of HPr during sleep and the occurrence of rapid eye movement (REM) sleep. However, HGH release during sleep was not remarkably influenced by 1-DOPA.

These results suggest that central catecholaminergic neural mechanisms are related to both sleep-related HPr release and REM sleep, but do not play an important role in sleep-related HGH release.
SECOND ANTIBODY CHEMICALLY LINKED TO CELLULOSE FOR THE SEPARATION OF BOUND AND FREE HORMONE: AN IMPROVEMENT OVER SOLUBLE SECOND ANTIBODY IN GONADOTROPHIN RADIOIMMUNOASSAY
Authors: Koninckx Ph. , Bouillon R. , De Moor P.
Published: December 2008

Coupling the second antibody to a solid pase (DASP) was found to be a definite improvement over the classical technique of soluble second antibody (DA) separation of bound and free hormone in the radioimmunoassays of gonadotrophins in plasma or in serum.

The duration (2.5 to 7.5 min) and the pH (10.5 to 12.5) of the cyanogen bromide activation of microcristalline cellulose did not affect the coupling capacity or the immunoreactivity of the second antibody, nor did it augment aspecific adsorption of free gonadotrophin on the cellulose matrix. Precision of duplicates was comparable for both methods but the accuracy and the detection limit of the solid phase system were higher due to a better separation of bound and free hormone, to the lower blank value and to the absence of aspecific interference of protein concentration.

Cost was lower since much less second antibody was needed in the solid phase system than in the soluble system and since the experimental procedures were simplified by the absence of prozoning effect and the solid nature of the cellulose matrix.
BINDING OF L-TRIIODOTHYRONINE TO ISOLATED RAT LIVER AND KIDNEY NUCLEI UNDER VARIOUS CIRCUMSTANCES
Authors: Docter R. , Visser T. J. , Stinis J. T. , van den Hout-Goemaat N. L. , Hennemann G.
Published: December 2008

Triiodothyronine (T3) is specifically bound by nuclei from rat liver and kidney. Binding of T3 at 37°C reaches its maximum at 30 min. In the presence of EDTA (to remove Mg2+) T3 binds to a class of binding sites with an estimated equilibrium association constant (Ka) of 3.3 × 1010 m−1 and a maximal binding capacity (MBC) of 3.8 fmol T3/100 μg DNA. In the presence of MgCl2 T3 binds to a second class of binding sites with an estimated Ka of 4.8 × 108 m−1 and a MBC of 123 fmol/100 μg DNA. Among the analogues tested, binding - relative to T3 - of D-T3, triiodothyroacetic acid and desamino-T3 is the same for both classes of binding sites, but relative affinity of thyroxine, D-T4, tetraiodothyroacetic acid and desamino-T4 is 2.5 to 6 times higher for the second class of binding sites than for the first class.

The presence of a cytosol binding protein is not a prerequisite for binding of T3 to the nucleus.
ACTION OF CYCLIC ADENOSINE 3′,5′ MONOPHOSPHATE ON L-14C-LEUCINE INCORPORATION IN A SYSTEM OF ROUGH MICROSOMES FROM BOVINE THYROID GLAND
Authors: Wägar Gustav
Published: December 2008

The effect of cAMP and varying concentrations of potassium (18–72 mM) on the incorporation of L-14C-leucine into TCA-precipitable protein was studied in a cell-free system comprising rough thyroid microsomes. cAMP (2 mm) alone or in combination with theopylline increased the incorporation of leucine into ribosome-bound (after DOC treatment) and extra-vesicular material, but had no significant effect on the DOC-released intravesicular material. Increase of the K+ concentration from 18 mm to 72 mm affected the incorporation of leucine into the microsomal compartments in much the same way as cAMP did.

The effect of cAMP and potassium seems to be due in partly to enhanced activation of amino acids, since in a system of pH5 fraction and cell sap, both cAMP and K+ increased the incorporation of 14C-leucine into cold TCA-precipitable material. Experiments with 14C-leucyl-tRNA as a marker suggest that the effect of cAMP and K+ is a consequence not only of increased activation of amino acids, but also of increased binding of activated amino acyl-tRNA to ribosomes.
ENHANCED BILIARY THYROXINE EXCRETION IN RATS TREATED WITH PREGNENOLONE-16α-CARBONITRILE
Authors: Japundžić M. M. , Bastomsky C. H. , Japundžić I. P.
Published: December 2008

Normal rats were treated with pregnenolone-16α-carbonitrile (PCN) 10 mg/100 g by stomach tube twice daily for 3 days. In these animals the biliary excretion of intravenously injected 125I-thyroxine (T4) was enhanced and the bile: plasma 125I ratio (B/P ratio) and the biliary clearance rate of plasma 125I-T4 was increased. Normal rats were treated with PCN for 3 days and homozygous Gunn rats for 13 days. In both groups PCN enhanced the bile flow and elevated the B/P ratios and the biliary clearance rate of plasma T4 following ip injection of 125I-T4 17 h previously. PCN-treatment had no effect on the fractions of biliary 125I present as T4-glucuronide, T4 and I− in either the normal or Gunn rats. Treatment with PCN for 10 days produced goitres in normal and Gunn rats and in normal rats elevated the serum TSH (bioassay) levels and the 17 h thyroid 131I uptake as well as the serum PB125I concentrations, without affecting stable PBI concentrations. These data indicated increased pituitary TSH release in response to increased peripheral metabolism of thyroid hormone; enhanced hormonal release from the thyroid kept pace with the accelerated peripheral loss.
DIFFERENCES IN ACTION OF LH AND FSH ON THE FORMATION OF CYCLIC AMP IN THE PREPUBERTAL RAT OVARY
Authors: Selstam Gunnar , Rosberg Sten , Liljekvist Jan , Grönquist Lena , Perklev Torsten , Ahrén Kurt
Published: December 2008

The actions of LH (NIH-LH-B8) and FSH (NIH-FSH-S9) on the cyclic AMP (cAMP) system in ovaries of 23–24 day old rats have been analyzed. An intravenous injection of LH increased ovarian cAMP levels in vivo after only 20 seconds. Maximal cAMP levels were seen after 15 min. Addition of LH or FSH in vitro to the isolated ovaries produced dose dependent increases of cAMP in the tissue as well as in the incubation medium. Low concentrations of LH caused a release of cAMP into the incubation medium without any detectable change in the tissue levels. The levels of cAMP in the incubation media for all concentrations of FSH were lower than the tissue levels, whereas for LH the opposite was found. In time-course experiments where the concentrations of LH (10 μg/ml) and FSH (100 μg/ml) were chosen to give similar tissue levels of cAMP, the release of the cyclic nucleotide into the incubation medium was approximately 2–3 times greater for LH than for FSH at the time periods studied (5–240 min). When LH and FSH were tested together in high concentrations, their effects were additive. When the ovaries were first incubated with FSH for 120 min followed by an incubation with LH, the stimulatory effect of LH was considerably reduced. When the order of the incubations was reversed, however, LH did not change the response to FSH. The results show that both LH and FSH have intrinsic effects on the cAMP system in the prepubertal rat ovary, but that the effects of the two gonadotrophins are not identical.
HYPOTHALAMIC-PITUITARY-TESTICULAR SYSTEM AND ADRENOCORTICAL FUNCTION
Authors: Verjans H. L. , Eik-Nes K. B.
Published: December 2008

Effect of intramuscular administration of ACTH or dexamethasone on blood serum levels of testosterone, LH and FSH was examined in intact and castrated, adult, male rats. Six IU ACTH or 1 mg dexamethasone were given daily for 7 days. Corticotrophin treatment had no influence on circulating testosterone, LH and FSH in intact or castrated male rats. Dexamethasone administration resulted in a slight elevation of serum FSH in intact animals but not in castrates. LH and testosterone remained normal in both intact and castrated animals injected with dexamethasone. Under our conditions of study the secretions from the adrenal gland appear to be insignificant for the regulation of pituitary secretion of gonadotrophins in the male rat.
PRE-OPERATIVE LOCALIZATION OF HYPERFUNCTIONING PARATHYROID TISSUE BY PARATHYROID SCINTIGRAPHY
Authors: Burckhardt P. , Bischof-Delaloye A. , Ruedi B. , Delaloye B.
Published: December 2008

In 22 patients who underwent surgery suspected of primary hyperparathyroidism, the surgical findings were compared with the results obtained by pre-operative parathyroid scanning and biochemical screening. Thirteen of 15 parathyroid adenomas were localized by pre-operative scanning, but in five of them a false positive focus was also described. The technique was less useful in primary hyperplasia. Comparable results were reported by other investigators. In both instances the best results were obtained in patients with high parathyroid activity as measured by plasma calcium, plasma alkaline phosphatase and tubular reabsorption of phosphorus (TRP). Parathyroid scintigraphy was especially helpful in the presence of ectopic adenomas and in patients who had undergone previous parathyroid surgery. Unfortunately, the possibility of false positive results makes it unreliable for the diagnosis of primary hyperparathyroidism.
FREE CORTISOL IN OBESITY; EFFECT OF FASTING
Authors: Galvão-Teles A. , Graves Linda , Burke C. W. , Fotherby K. , Fraser Russell
Published: December 2008

Plasma and urinary corticosteroids were measured in 13 obese subjects before and after high and low protein diets, and after fasting. During isocaloric high and low protein diets, urinary 17-oxogenic steroids and to a lesser extent urinary free cortisol excretion rose and fell in parallel with protein intake. Plasma unbound cortisol levels were not much changed by high or low protein intake.

However, during 7 to 11 days total fasting, there was a highly significant rise in plasma unbound cortisol at 24.00. A smaller rise occurred at 09.00. The overall effect was a considerable diminution of the day-night variation of plasma unbound cortisol levels during fasting, and a rise in prevailing unbound cortisol levels and urinary free cortisol excretion. In 3 subjects tested these changes were reversed immediately by glucose re-feeding.
PLASMA STEROID AND PROTEIN HORMONE CONCENTRATIONS IN PATIENTS WITH PROSTATIC CARCINOMA, BEFORE AND DURING OESTROGEN THERAPY
Authors: Harper M. E. , Peeling W. B. , Cowley T. , Brownsey B. G. , Phillips M. E. A. , Groom G. , Fahmy D. R. , Griffiths K.
Published: December 2008

Plasma testosterone, androstenedione, oestradiol-17β, follicle stimulating hormone (FSH) and luteinizing hormone (LH) were not significantly different in patients with prostatic cancer, with benign prostatic hyperplasia or in patients without prostatic disease. Plasma prolactin concentrations were significantly lower in the patients with benign disease than those with prostatic carcinoma. Endocrine therapy in the form of stilboestrol administration significantly decreased plasma levels of testosterone, oestradiol-17β, FSH and LH within 7 days of the treatment. After 7 days therapy prolactin levels increased significantly in all patients studied. Changes in growth hormone concentrations were more varied in response to stilboestrol, being elevated in several patients and remaining unchanged in others. Treatment of a few prostatic carcinoma patients who were receiving stilboestrol therapy with CB154, an inhibitor of prolactin secretion, brought an immediate decrease in prolactin levels which was sustained. Plasma testosterone, androstenedione and growth hormone were unchanged in these patients but a significant decrease in plasma oestradiol-17β was noted in two patients during CB154 administration.
INHIBITION OF THYROGLOBULIN BIOSYNTHESIS AND DEGRADATION BY EXCESS IODIDE. SYNERGISM WITH LITHIUM
Authors: Radvila A. , Roost R. , Bürgi H. , Kohler H. , Studer H.
Published: December 2008

Lithium and excess iodide inhibit the release of thyroid hormone from preformed stores. We thus tested the hypothesis that this was due to an inhibition of thyroglobulin breakdown. Rats were pre-treated with propylthiouracil (PTU) for 3 weeks in order to deplete their thyroids of thyroglobulin. While the PTU was continued, lithium chloride (0.25 mEq./100 g weight) or potassium iodide (3 mg per rat) were injected every 12 h for 3 days. Thereafter the thyroglobulin content in thyroid gland homogenates was measured. PTU pre-treatment lowered the thyroglobulin content from 4.21 to 0.22 mg/100 mg gland. Lithium caused a marked re-accumulation of thyroglobulin to 0.60 mg/100 mg within 3 days. While iodide alone had only a borderline effect, it markedly potentiated the action of lithium and a combination of the two drugs increased the thyroglobulin content to 1.04 mg/100 mg.

Thyroxine was injected into similarly pre-treated animals to suppress secretion of thyrotrophic hormone. This markedly inhibited the proteolysis of thyroglobulin and 1.3 mg/100 mg gland accumulated after 3 days. Excess iodide, given in addition to thyroxine, decreased the amount of thyroglobulin accumulated to 0.75 mg/100 mg gland. To study whether this could be explained by an inhibitory action of iodide on thyroglobulin biosynthesis, thyroid glands from animals treated with excess iodide were incubated in vitro in the presence of 0.2 mm iodide for 3 h. Iodide decreased the incorporation of radioactive leucine into total thyroidal protein and into thyroglobulin by 25 and 35 % respectively. Iodide did not inhibit protein synthesis in the kidney, liver or muscle tissue. Thus, large doses of iodide selectively inhibit thyroglobulin biosynthesis.
A TRANSIENT RISE OF HORMONE SECRETION: A RESPONSE OF THE STIMULATED RAT THYROID GLAND TO SMALL INCREMENTS OF IODIDE SUPPLY
Authors: Studer H. , Bürgi H. , Kohler H. , García M. C. , de Escobar G. Morreale
Published: December 2008

Small doses of iodide (2 times 3.2 μg at 12 h interval), below those capable of inducing Wolff-Chaikoff effect, were injected into rats kept on a moderately low iodine diet. By means of a 125I equilibration technique as well as by direct measurement of cold T4, it was demonstrated that the level of circulating PB125I (representing iodothyronines as confirmed by column chromatography) increased by a mean of 40% within 24 h following the first iodide injection. The serum TSH concentration (measured by radioimmunoassay) was simultaneously depressed.

Thus, in stimulated thyroid glands, a biologically significant fraction of an iodide load escapes autoregulatory control of iodothyronine synthesis. A small, transient increase of hormone release is likely to represent the physiological response of a normal gland to a sudden supplement of iodide supply. The ensuing depression of TSH secretion may be necessary for final adjustment of thyroid function. It is considered to be the last step in a cascade of mechanisms whose interaction keeps the thyroidal hormone output within narrow limits in the face of a fluctuating iodide supply. Failure of one or several of these mechanisms in the goitrous human gland could conceivable explain the phenomenon of "Jod Basedow".
EFFECT OF SOMATOSTATIN ON BASAL AND GLUCOSE INDUCED INSULIN RELEASE IN FIVE PATIENTS WITH HYPERINSULINAEMIA
Authors: Efendić S. , Lins P. E. , Sigurdsson G. , Ivemark B. , Granberg P. O. , Luft R.
Published: December 2008

Somatostatin in a dose of 490 μg over 90 min inhibited basal insulin release in one subject with hyperplasia of the pancreatic islets and in two with benign insulin secreting adenomas. These three subjects also showed a marked insulin response to glucose infusion. No inhibitory effect of somatostatin was observed in two patients with benign insulinomas who demonstrated only a minor response to glucose. In the patient with islet hyperplasia and in one of the adenoma patients, who had an exaggerated insulin response to glucose (maximal response 10–30 times the basal insulin value), somatostatin also suppressed glucose induced insulin release. Our data suggest a beneficial therapeutic effect of somatostatin in patients with spontaneous hyperinsulinism with a pronounced insulin response to glucose.
REDUCTION OF 3-OXOSTEROIDS IN HUMAN LIVER MICROSOMES
Authors: Björkhem Ingemar , Einarsson Kurt , Hellers Göran , Wikvall Kjell
Published: December 2008

The 3α- and 3β-reduction of the following steroids was studied in human liver microsomes: 5α-androstane-3,17-dione, 17β-hydroxy-5α-androstan-3-one, 5α-pregnane-3,20-dione, 5β-pregnane-3,20-dione, 3-oxo-5β-cholanoic acid and 7α-hydroxy-5α-cholestan-3-one. With NADH as cofactor there was a preferential 3α-reduction of the C19- and C21-3-oxo-steroids and a preferential 3β-reduction of the C24- and C27-3-oxo-steroids. Substitution of NADH with NADPH influenced reduction of the substrates in different ways, indicating the presence of several 3α- and 3β-hydroxysteroid dehydrogenases with different substrate specificity and specificity towards NADH and NADPH. Only small or insignificant sex differences could be observed in the reductions studied.
TRANSLATION OF AVIDIN mRNA FROM CHICK OVIDUCT IN THE OESTROUS MOUSE UTERUS
Authors: Tuohimaa Pentti , Soderling Eeva
Published: December 2008

Oestrogen-primed immature chicks were injected with 5.0 mg of progesterone. Twenty hours after progesterone avidin mRNA was isolated and purified by a method including an antibody precipitation of the avidin polysomes, phenol extraction and nitrocellulose trapping. A water solution of mRNA (1 μg) with [14C]amino acids was instilled into the uterine horn of oestrous or dioestrous mice. Saline and [14C]amino acids were injected into the opposite control uterine horn. Avidin was assayed by an antibody method. A clear-cut avidin synthesis was found in the oestrous uterus, whereas the dioestrous showed only a slight avidin synthesis. This suggest that there are no absolute species-specific factors required at the translational level of uterine protein synthesis and that the mammalian uterus can translate foreign hormone-specific proteins at a rate dependent on the endogenous protein synthesis.
DIFFERENCES IN URINARY EXCRETION OF STEROID 21-DEOXYKETOLS BY WOMEN PREGNANT WITH A NORMAL OR AN ANENCEPHALIC FOETUS
Authors: Adejuwon C. A. , Heys R. F. , Oakey R. E.
Published: December 2008

During late pregnancy the urinary excretion of steroid 21-deoxyketols, which contain the CH3-CO-C(OH)< side chain, was 1.16 ± 0.50 mg/24 h (mean ± sd n = 9). The mean excretion of these metabolites in 8 pregnancies with an anencephalic foetus showed a significant reduction (P < 0.01, t-test) to 0.42 ± 0.18 mg/24 h. Six untreated non-pregnant women and 7 taking oral contraceptives which contain oestrogen had steroid 21-deoxyketol excretions of 0.26 ± 0.09 mg/24 h and 0.19 ± 0.09 mg/24 h respectively.

These results imply that the adrenal of the normal foetus makes a contribution to the secretion of those steroids which are ultimately excreted by the mother as 21-deoxyketols.
DIMINISHED SENSITIVITY OF THE INSULIN RESPONSE TO GLUCOSE FOLLOWING GROWTH HORMONE INFUSION IN MAN
Authors: Adamson Ulf , Cerasi Erol
Published: December 2008

The acute effect of growth hormone (GH) administration on the dose-kinetics of glucose-stimulated insulin release was investigated in eight healthy, non-obese male subjects. The glucose-insulin dose-response relationship in these subjects was established by performing glucose infusions at three different dose levels. In a second series of experiments, the glucose infusions were preceded by a 30 min infusion of GH (40 μg/kg body weight), terminated 60 min before administration of glucose. GH induced small but significant reductions in the basal levels of blood glucose and plasma insulin. The glucose tolerance (k-value) was diminished after GH at all glucose doses. Both the initial late phases of insulin response to glucose were impaired following GH treatment. This effect was most pronounced when the intermediary glucose dose (eliciting a blood glucose level around 300 mg/100 ml) was used. Thus, the insulinogenic index (whole period of stimulation) was reduced by GH to 88.9 ± 7.6, 60.4 ± 7.1 and 74.3 ± 11.0% of the respective controls when the smallest, the intermediate, and the largest glucose loads, respectively, were given.

The blood glucose-plasma insulin dose-response curves were shifted to the right of the control ones when glucose infusion was preceded by GH. These findings suggest that GH diminishes the sensitivity of the islet for the insulin releasing action of glucose.

Some possible mechanisms by which GH may modify insulin release are discussed.
STUDIES ON THE MECHANISM OF SOMATOSTATIN ACTION ON INSULIN RELEASE
Authors: Efendić S. , Claro A. , Luft R.
Published: December 2008

In man, 3 μg per kg per 90 min of linear somatostatin significantly inhibited basal as well as arginine induced insulin and glucagon release. One μg per kg per 90 min of somatostatin significantly inhibited basal insulin release but not basal glucagon release or arginine induced insulin and glucagon release.

In the perfused rat pancreas, as little as one ng per ml of perfusate of somatostatin significantly inhibited arginine induced insulin but not glucagon release, while 10 ng per ml of somatostatin by more than 50 per cent reduced the effect of arginine on insulin and glucagon release. Thus, linear somatostatin seemed to be a slightly more potent inhibitor of insulin than of glucagon release in man and in the perfused rat pancreas.
BIOGENESIS OF CORTICOSTEROIDS IN MONOLAYER CULTURES OF HUMAN FOETAL ADRENAL CELLS
Authors: Goodyer Cynthia G. , Torday John S. , Hall C. St. George , Smith Barry T. , Giroud C. J. P.
Published: December 2008

Human foetal adrenal cells were grown in monolayer culture and their steroidogenic capacity observed for up to a month. The cells produced a complex array of steroids and some of their ester sulphates from endogenous as well as from [14C] and [3H] precursors.

ACTH stimulated corticoidogenesis, particularly cortisol secretion, and markedly enhanced the incorporation of progesterone and pregnenolone into cortisol. Following incubation with the same precursors, large amounts of radioactivity remained water soluble. From the butanol extractable material of this fraction, dehydroepiandrosterone sulphate was characterized as the main metabolite of pregnenolone and corticosterone and 11-deoxycorticosterone sulphates as the main metabolites of progesterone. With time in culture there was a decrease in steroidogenesis as well as a steady decline in responsiveness to ACTH, mainly manifested by cortisol secretion. The medium from homologous foetal pituitary cultures stimulated cortisol production by the human adrenal cell monolayer.
EFFECT OF PROLACTIN, GROWTH HORMONE AND INSULIN ON THE UPTAKE AND BINDING OF DIHYDROTESTOSTERONE TO THE CULTURED RAT VENTRAL PROSTATE
Authors: Johansson Risto
Published: December 2008

The effects of prolactin, growth hormone and insulin on the total uptake and specific binding of tritiated dihydrotestosterone in the cultured rat ventral prostate were examined. In similar conditions prolactin and insulin act synergistically with testosterone on the macromolecule synthesis of the prostate, but have no effect on the conversion of testosterone to dihydrotestosterone.

The total uptake of tritiated dihydrotestosterone to the tissues was slightly, but not statistically significantly, increased by prolactin, insulin and growth hormone. The majority of the radioactive dihydrotestosterone in the tissue was in free form or very loosely bound. None of these three hormones altered the binding of tritiated dihydrotestosterone to the cytoplasmic receptors.

Non-radioactive dihydrotestosterone, cyproterone and cyproterone acetate in 1000 foid excess strongly decreased the binding of tritiated dihydrotestosterone to the cytoplasmic reseptors and to the nuclei. That part of the binding, which was inhibited by the hormones was considered to represent the specific binding to the receptors. Insulin stimulated both the specific and the unspecific uptake of dihydrotestosterone to the nuclei. Prolactin only stimulated the specific uptake to the nuclei while growth hormone had no effect.

Autoradiography of the nuclear fraction indicated a firm binding of tritiated dihydrotestosterone to the nuclei. The radioactivity of the other contaminating cell components in this fraction appeared to be negligible.
PROLACTIN AND THE PITUITARY-GONADAL AXIS IN MALE URAEMIC PATIENTS ON REGULAR DIALYSIS
Authors: Hagen C. , Ølgaard K. , McNeilly A. S. , Fisher R.
Published: December 2008

In 21 consecutive adult male patients with chronic renal failure on regular haemo- or peritoneal dialysis, the plasma levels of prolactin (hPr), growth hormone (HGH), thyrotrophin (TSH), luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T) and sex hormone binding globulin (SHBG) were measured.

Elevated levels of hPr were found in 16 of the patients and could not only be explained by the medicamentation. All the patients studied showed an inverse ratio of LH to FSH with higher levels of FSH than LH and 15 of the 21 patients had elevated plasma concentrations of FSH, while only 4 had elevated LH.

No significant difference in any of the hormone levels could be demonstrated before and after dialysis, and no significant correlation between the hormone levels and the time of dialysis, the type of dialysis or the age of the patient was found. However, 8 of the 21 patients showed higher levels of HGH before than after dialysis.

Impotency was found in 11 of the patients, but was not related to abnormal levels of hPr, LH, FSH, T or SHBG.
INHIBITION OF INSULIN RELEASE BY CYPROHEPTADINE: EFFECTS ON 3′,5′-CYCLIC-AMP-CONTENT AND 45Ca-ACCUMULATION OF INCUBATED MOUSE ISLETS
Authors: Joost H. G. , Beckmann J. , Lenzen S. , Hasselblatt A.
Published: December 2008

Cyproheptadine (1, 10 and 100 μm) significantly reduced insulin release from isolated mouse islets in response to glucose. In contrast, 1 mm cyproheptadine induced a large release of insulin into the incubation medium probably due to islet cell damage, since the islets had lost a considerable amount of their protein content. 3′,5′-cyclic-AMP-levels of the islets were not significantly affected by 10 μm cyproheptadine in the presence as well as in the absence of theophylline (10 mμ). As the inhibitory effect of cyproheptadine on insulin release was correlated with reduced accumulation of calcium-45, the agent may inhibit insulin release by interfering with the calcium handling of the β-cell.
THE EFFECT OF CYPROTERONE ACETATE ON THE ADRENAL OF THE MALE HAMSTER
Authors: Zieger G. , Lux B. , Kubatsch B.
Published: December 2008

Administration of different doses of cyproterone acetate (CPA) to male hamsters for 5 weeks slows down the growth of the adrenals and the increase in body weight. This effect is still present 4 weeks after cessation of CPA treatment, though some recovery can be seen. Histological and histometrical evaluations confirm an atrophy of the adrenal, particularly in the zona fasciculata and in higher doses also in the zona reticularis. After operative castration it is the zona reticularis which shows the most marked atrophic changes. It is therefore concluded, that CPA possesses besides its anti-androgenic properties an inhibiting corticoid-like effect on the adreno-pituitary feed-back mechanism.