bluuebunny/crossref_metadata_2025 huggingface dataset:
PROPERTIES OF HUMAN GONADOTROPHINS ELUTED FROM HUMAN CORPUS LUTEUM AND MOUSE LUTEOMA LH-HCG RECEPTORS
Authors: Cole F. E. , Arquembourg P. C. , Rice B. F.
Published: December 2008

Studies were performed to try to determine if gonadotrophins are altered during their interaction with tissue receptors. Immunologic, electrophoretic and binding properties of lactoperoxidase labelled [125I]HLH and [125I]HCG were examined before and after elution from mouse luteoma and human corpora lutea receptor preparations. The anti-HCG used in these studies at a 1:10 000 dilution precipitated 92% of a freshly iodinated [125I]HCG preparation. Receptor eluted [125I]HCG, derived from the same batch of labelled ligand, was virtually quantitatively precipitated by the same dilution of anti-HCG. [125I]HCG eluted from the human corpus luteum was electrophoretically more homogenous when compared to its heterogenous parent labelled preparation and migrated to a position similar to that of native HCG.

In Ouchterlony double diffusion experiments against anti-HCG antiserum, corpus luteum eluted [125I]HCG and [125I]HLH showed immunologic identity with each other as well as with native HCG and HLH. Receptor eluted [125I]HCG from the mouse luteoma, following in vivo administration via tail vein injection or after incubation in vitro with labelled hormones, was immunologically indistinguishable from native HCG.

The electrophoretic mobility of HCG was retarded when HCG was added to extracts of mouse luteoma, liver and kidney. Eluates of mouse luteoma, applied to Bio-Gel columns previously equilibrated with [125I]HCG showed the ability to concentrate [125I]HCG in the high molecular weight column fractions. Similar results were obtained with columns equilibrated with [125I]TSH and [125I]HGH. [125I]HCG eluted from the mouse luteoma was able to bind to fresh luteoma homogenate but, in contrast to an earlier report with [125I]HCG eluted from rat testis, no enhancement of binding of the eluted [125I]HCG was observed with fresh tissue. These results could be explained by the extraction of non-dialyzable intracellular component during the [125I]HCG elution procedure from the luteoma homogenate which combines with HCG to lower its binding and alter its electrophoretic mobility. This component could be extracted from other mouse tissues and combines with other labelled peptide hormones. Data in the present report support in part the hypothesis that gonadotrophins eluted from mouse luteoma and human corpus luteum are not altered by their interaction with tissue receptors.
PITUITARY AND GONADAL FUNCTION IN PATIENTS WITH THE LAURENCE-MOON-BIEDL SYNDROME
Authors: Pérez-Palacios G. , Uribe M. , Scaglia H. , Lisker R. , Pasapera A. , Maillard M. , Medina M.
Published: December 2008

Pituitary and gonadal functions were evaluated in two pre-pubertal male siblings and in one unrelated adult male with the complete form of the Laurence-Moon-Biedl syndrome. The adult patient (19 years old) presented lack of secondary sex characteristics, azoospermia, and sub-normal external genitalia development. Testicular biopsy showed an arrest of spermatogenesis and diminished number of Leydig cells. Low plasma testosterone levels and normal responsiveness to HCG administration were found. A significant rise of pituitary gonadotrophin after LH-RH stimulation and a lack of response to clomiphene citrate was demonstrated. The pre-pubertal siblings (9 and 11 years old) had genital hypoplasia and undetectable plasma levels of testosterone, though there was a significant rise after HCG stimulation. Plasma gonadotrophin levels were within the assay sensitivity limits and a normal pituitary responsiveness following LH-RH stimulus was noted. Slightly low excretion of urinary 17-OH-corticosteroids which increased significantly after ACTH and metyrapone was demonstrated in both patients. Elevated levels of serum lipoproteins and triglycerides were found in all cases. These results are interpreted as demonstrating the suprahypophyseal origin of the dysfunction thus producing hypogonadism observed in the adult patient, and suggesting that a similar dysfunction might account for the genital hypoplasia in the pre-pubertal boys with this inherited disorder.
PLASMA SEX HORMONE-BINDING GLOBULIN BINDING CAPACITY IN BENIGN PROSTATIC HYPERTROPHY AND PROSTATIC CARCINOMA: COMPARISON WITH AN AGE DEPENDENT RISE IN NORMAL HUMAN MALES
Authors: Dennis M. , Horst H.-J. , Krieg M. , Voigt K. D.
Published: December 2008

A method for the routine determination of plasma sex hormone-binding globulin (SHBG) binding capacity is introduced. In normal males an age dependent increase in SHBG binding capacity from 2.85 × 10−8 m in the age range 22–44 years to 4.66 × 10−8 m in the age range 45–64 years was found. A higher mean value of 6.41 × 10−8 m was obtained in normal females, 20–40 years old, and still higher values were found in females taking oral contraceptives. Although in male groups with benign prostatic hypertrophy or prostatic carcinoma the mean ages were somewhat higher than in the older normal group, a further age dependent increase in SHBG binding capacity in these diseases could not be demonstrated. In fact the mean values found were slightly although not significantly lower at 4.07 and 3.89 × 10−8 m, respectively. As expected, oestrogen treatment of males with prostatic carcinoma produced higher values.
FAMILIAL IDIOPATHIC HYPOGONADOTROPHIC HYPOGONADISM
Authors: Bétend B. , Lebacq E. , David L. , Claustrat B. , François R.
Published: December 2008

A new case of familial idiopathic hypogonadotrophic hypogonadism is presented: 3 males and 2 females among 9 siblings are affected. Very low to non-detectable levels of plasma LH and FSH levels were found in each patient. LH-RH stimulation test gave in one male a slight increase in plasma LH levels while no change was observed in the others. Prolonged treatment with gonadotrophins or testosterone gave poor results in the males while evidence of ovulation was obtained in the two females during a unique induced artificial cycle with combined HMG and HCG treatment; rapid feminization was also obtained in the females with oestrogen therapy. The striking difference in the results of the substitution treatments between males and females suggest that some degree of acquired insensitivity of the testes to gonadotrophins and of peripheral tissues to male sex hormones are present in male hypogonadotrophic hypogonadism. This may be the consequence of a lack of hormonal stimulation or impregnation during infancy and childhood.
PROGESTERONE TREATMENT INCREASES PITUITARY OESTRADIOL RETENTION IN THE OVARIECTOMIZED NORMAL FEMALE RAT BUT NOT IN THE MALE NOR IN THE ANDROGEN- OR OESTROGEN-STERILIZED FEMALE RAT
Authors: Lisk Robert D. , Reuter Lawrence A.
Published: December 2008

Pituitary retention of [3H]oestradiol in ovariectomized rats was measured following in vivo progesterone pre-treatment and found to be significantly increased after 48, 72, 96 and 120 h of pre-treatment. Increased [3H]oestradiol retention was also observed for at least up to 72 h after removal of the progesterone pre-treatment source. This retention was measured as dpm per mg dry tissue weight. [3H]Oestradiol retention was also measured in the nuclear fraction of tissues incubated with [3H]oestradiol in vitro. Following 72 h of in vivo progesterone pre-treatment, the nuclear fraction from the pituitary was found to retain significantly more [3H]oestradiol than corresponding fractions from non-treated animals. In contrast to ovariectomized females, no increase in [3H]oestradiol retention was found in the pituitary of orchidectomized males pre-treated with progesterone for 72 h.

[3H]Oestradiol retention by pituitaries of ovariectomized rats injected on the day of birth with 200 μg oestradiol benzoate (OeB) or 500 μg testosterone propionate (TP) was significantly decreased in comparison to control animals. When the rats were pre-treated in vivo with oestradiol for 6 or 72 h and [3H]oestradiol retention was measured 6 or 24 h after this pre-treatment, the OeB and TP treated animals retained significantly less [3H]oestradiol under most treatment conditions. Progesterone pretreatment for 24 or 72 h in vivo followed by measurement of [3H]oestradiol retention immediately or 6 or 24 h later resulted in a significant increase in [3H]oestradiol retention for the control animals. In contrast, the neonatally OeB or TP treated animals differed significantly by not showing increased retention.

When [3H]oestradiol retention of the pituitary was measured in vitro following homogenization at 0°C and incubation at 37°C for 1 h, the nuclear fraction from both OeB and TP treated animals was found to retain less hormone per unit DNA; however, this decrease was significant only for the TP animals. Thus, males and androgen- or oestrogensterilized females have an altered and reduced augmentation of pituitary oestradiol retention in response to both oestrogen and progesterone pretreatments.
A MICROGEL ELECTROPHORETIC ANALYSIS OF THE COLLOID IN SINGLE RAT THYROID FOLLICLES DURING THYROXINE SUPPRESSION
Authors: Smeds Staffan , Anderberg Bo
Published: December 2008

A sequential study of the effect of thyroxine (T4) on the protein composition of the colloid in the rat thyroid gland has been carried out in 24 rats. Daily ip injections of 20 μg thyroxine were given and the colloid was analyzed after 1, 2, 3 and 4 days and 1, 2 and 3 weeks. The protein constituents were separated by microgel electrophoresis and measured by microdensitometry. The incorporation of [3H]leucine into the thyroglobulin fraction and into the albumin-like protein in the homogenate of the gland was analyzed after T4 suppression for 2 days. The 2 h thyroidal iodine uptake was analyzed during the first week of T4 administration. During the second and the third day of T4 administration, the amount of 27S and larger complexes of thyroglobulin was reduced by 30–40 per cent and the amount of the albumin-like protein was significantly increased and present in almost all samples. Preliminary data indicated that during the same period the relative amount of [3H]leucine activity was increased in the albumin-like protein fraction compared to the thyroglobulin fraction in the thyroid. It is concluded that the exocytotic vesicles contain the albumin-like protein. The results further indicate that the administration of T4 temporarily changes the relative rates of formation of thyroglobulin and of the albumin-like protein in the follicle.
PITUITARY-GONADAL FUNCTION IN MALE PATIENTS WITH MYOTONIC DYSTROPHY - SERUM LUTEINIZING HORMONE, FOLLICLE STIMULATING HORMONE AND TESTOSTERONE LEVELS AND HISTOLOGICAL DAMAGE OF THE TESTIS
Authors: Takeda Ryoyu , Ueda Misao
Published: December 2008

Variations in serum levels of LH and FSH after administration of synthetic LH-RH, and basal levels of serum testosterone were studied in 9 male patients with myotonic dystrophy. The degree of testicular damage, as determined histologically on biopsy specimens, was also studied. Results were as follows: 1) it was observed that both the basal and stimulated (maximal) levels of serum LH and FSH were significantly higher than levels found in 9 sex- and age-matched normal controls. 2) The basal level of serum testosterone was consistently lower in the patient group. One patient, however, showed a low normal level, which represented a statistically significant reciprocal relation to both LH and FSH levels as expressed on a logarithmic scale. 3) There was a significant trend which indicated that the higher the serum LH, FSH levels, or the lower the basal levels of serum testosterone, the more extensive was the damage to the seminiferous tubules. From these findings it was concluded that hypogonadism in patients with myotonic dystrophy, is characterized by the development of lesions in the seminiferous tubules.
LOCALIZATION OF PROLACTIN BINDING IN PROSTATE AND TESTIS: THE ROLE OF SERUM PROLACTIN CONCENTRATION ON THE TESTICULAR LH RECEPTOR
Authors: Aragona Cesare , Bohnet Heinz G. , Friesen Henry G.
Published: December 2008

Specific binding sites for prolactin (PRL) and gonadotrophins on ventral and dorsolateral prostate as well as on Leydig cells and tubules of testes of rats at different ages were examined. The binding sites for PRL were found in greatest number in ventral prostate and in Leydig cells. LH binding sites were also more numerous than FSH binding sites in the latter. FSH sites were greater than LH sites in tubular preparations obtained from the testis. Specific binding (SB) of PRL in the Leydig cells reached a maximum at 45 days (4%) and in the case of LH a maximum of 12% was obtained at 70 days. In both preparations SB of FSH exhibited a plateau between 20 and 40 days (11%) followed by a gradual decline to 6% at 100 days. Following 20 days of treatment with Bromocriptin beginning at 20 days serum PRL was suppressed and SB of LH to the Leydig cells was significantly decreased, whereas SB of PRL and FSH was unaffected.

These studies suggest that despite decreases in serum PRL, the number of PRL and FSH receptors remain unaltered. On the contrary, LH receptors in the rat testis are modulated by changes in serum PRL.
BINDING OF CHOLECALCIFEROL METABOLITES TO RAT DUODENAL MUCOSA CYTOSOL
Authors: Ulmann A. , Brami M. , Pezant E. , Garabedian M. , Funck-Brentano J. L.
Published: December 2008

In vitro binding of 25-hydroxycholecalciferol (25-(OH)D3) and 1α,25-dihydroxycholecalciferol (1,25-(OH)2D3) was studied in the duodenal mucosa cytosol of rachitic rats: both 25-(OH)D3 and 1,25-(OH)2D3 bind to a macromolecule (sedimentation coefficient 5.5 to 6 S in low or high ionic strength) with a high affinity (KD at 4°C = 1.2×10−9 m and 2×10−9 m, respectively). In addition, it is concluded from competition and chase experiments that 25-(OH)D3 binding sites differ from that for 1,25-(OH)2D3.
GLUCOSE TOLERANCE AND INSULIN SECRETION IN HYPERTHYROIDISM
Authors: Andersen O. Ortved , Friis Th. , Ottesen B.
Published: December 2008

To evaluate the glucose tolerance and insulin secretion in hyperthyroidism patients were examined in the toxic state and after they had been made euthyroid.

Fasting values:

In 42 untreated patients the glucose- and insulin concentrations in serum were significantly elevated. In 24 treated patients the glucose concentrations became normal, while the insulin concentrations remained elevated.

Oral-glucose-tolerance test:

In 20 untreated patients the glucose- and insulin responses were significantly increased. In 8 treated patients the glucose response became normal, while the insulin response remained unchanged.

Intravenous-glucose-tolerance test:

In 28 untreated patients the K-values were significantly decreased and the insulin response increased. In 23 treated patients the K-values rose significantly, but the insulin response remained unchanged.

Intravenous-tolbutamide test:

In 41 untreated patients the glucose concentration decreased significantly compared with the controls, and the insulin responses were significantly increased. In 23 treated patients the glucose concentrations decreased even more, while the insulin response remained unchanged.

The results indicate enhanced sensitivity or an increase in the mass of β-cells in hyperthyroidism. The glucose tolerance tests point to an increased peripheral insulin resistance. The normalized glucose tolerance and still enhanced insulin secretion during treatment support the assumption, that hyperthyroidism causes an increase in the β-cell mass.
ENDOCRINE MORBIDITY IN ADULTS TREATED WITH CEREBRAL IRRADIATION FOR BRAIN TUMOURS DURING CHILDHOOD
Authors: Shalet S. M. , Beardwell C. G. , MacFarlane I. A. , Jones P. H. Morris , Pearson D.
Published: December 2008

Hypothalamic-pituitary function was assessed in 20 adult subjects who were treated with cerebral irradiation for brain tumours during childhood between 8 and 32 years earlier. Nine patients showed impaired growth hormone (GH) responses to hypoglycaemia, of whom, 7 are below the third centile for standing height. All GH deficient subjects received more than 2950 rads to the hypothalamic-pituitary axis with a maximum dose of approximately 5000 rads being used in one case.

Three subjects have an elevated basal serum thyroid stimulating hormone (TSH) level and 2 of these show an exaggerated TSH response to thyrotrophin releasing hormone (TRH) but no patient was clinically or biochemically hypothyroid. The rest of hypothalamic-pituitary function was essentially normal.

This study shows that multiple pituitary hormone deficiencies do not develop with time when the radiation dose is below a critical level. Thus it appears that there is a gradation of radiation damage to the hypothalamic-pituitary axis which is dependent primarily on the dose received rather than the time interval after radiotherapy.
INFLUENCE OF LH/FSH RELEASING HORMONE (LRH) ON THE BASAL SECRETION OF GONADOTROPHINS IN RELATION TO PLASMA LEVELS OF OESTRADIOL, PROGESTERONE AND PROLACTIN DURING THE POST-PARTUM PERIOD IN LACTATING AND IN NON-LACTATING WOMEN
Authors: Jeppsson Sien , Rannevik Gunnar , Thorell Jan I. , Wide Leif
Published: December 2008

The pituitary responsiveness to LH/FSH releasing hormone (LRH) was studied in the puerperium in lactating and in non-lactating women. The response of both groups of patients to 25 μg LRH iv was tested 8–10 days, 15–17 days, and 29–32 days after a normal delivery at full term.

The basal levels of FSH were low during the first 10 days after delivery. A rise was then observed, and about 4 weeks after delivery levels above or in the upper normal range of a normal follicular phase were recorded. The levels were significantly higher in the lactating group. When compared with the normal follicular phase, the relative increase in FSH basal levels was higher than the increase in LH basal levels in both groups of patients.

The period of non-responsiveness of the pituitary to LRH was found to be of equal length in the two groups. In both groups the FSH response returned more rapidly than the LH response. About 2 weeks after delivery a reverse pattern of gonadotrophin response to LRH was seen with a FSH response that was greater than the LH response compared with what is generally observed in the various phases of the menstrual cycle in eumenorrhoeic women. This pattern was more pronounced in the lactating group about 4 weeks after delivery.

Oestradiol levels were low and roughly equal on the three test occasions in each group, but in the non-lactating group there was a tendency to higher concentrations. Prolactin levels were highest about one week after delivery and then showed a tendency to decrease, and this was more pronounced in the non-lactating group. Progesterone levels were invariably low in both groups.
COMPARISON OF THYROID ANTIGENS BY THE EXPERIMENTAL PRODUCTION OF PRECIPITATING ANTIBODIES TO HUMAN THYROID FRACTIONS AND THE IDENTIFICATION OF AN ANTIBODY WHICH COMPETES WITH LONG-ACTING THYROID STIMULATOR (LATS) FOR THYROID BINDING
Authors: von Westarp Christian , Knox Andrew J. S. , Row Vas V. , Volpé Robert
Published: December 2008

Antibodies were raised to various sub-cellular fractions of human thyroids, (of Graves' disease, Hashimoto's thyroiditis, and non-toxic goitre). With one exception it was found that antibodies to the Graves' thyroid fractions cross-reacted with both the non-toxic goitre and Hashimoto's thyroiditis fractions. This exception was in the antiserum to the Graves' 105 000 × g pellet (Gr4) which contained an antibody (A-1) that could not be absorbed by either the non-toxic goitre (NTG) or the Hashimoto's (H) thyroid preparations. The antibody-antigen reaction between A-1 and Gr4 could be blocked by the addition of LATS (or TSH) to the antigen, thus suggesting that A-1 might be a LATS-like immunoglobulin. These results suggest that the TSH receptor may be antigenic and that an antibody to this receptor can be produced in vivo. Production of such an antibody to the TSH receptor would permit the development for the first time of a good animal model of Graves' disease.
INACTIVATION OF SOMATOSTATIN BY PEPTIDASES IN DIFFERENT AREAS OF THE RAT BRAIN
Authors: Griffiths E. C. , Jeffcoate S. L. , Holland D. T.
Published: December 2008

With the availability of a sensitive and specific radioimmunoassay for growth hormone-release-inhibiting hormone (somatostatin or GH-RIH), it has been possible to investigate the presence of peptidase enzymes capable of inactivating this hypothalamic hormone in the hypothalamus and other brain areas of the rat. It was found that both supernatant and particulate fractions from male rat hypothalami rapidly inactivated somatostatin and that the enzymes involved have an optimum pH of 7.3. Peptidase activity was significantly higher in the supernatant than in the particulate fraction from the hypothalamus, thalamus, cortex and cerebellum. Besides confirming the presence of peptidases inactivating the release-inhibiting hormone in the hypothalamus (the site of somatostatin synthesis and release), the results may indicate that somatostatin has a functional significance outside the hypothalamus-anterior pituitary axis but within the central nervous system.
INFLUENCE OF EXPERIMENTAL HYPERTHYROIDISM ON SKELETAL MUSCLE METABOLISM IN THE RAT
Authors: van Hardeveld C. , Kassenaar A. A. H.
Published: December 2008

In this study hind-limb perfusion was used to investigate the influence of thyroid hormones on some metabolic parameters in the skeletal muscle of the rat.

Daily injection of 20 μg L-thyroxine (T4) per 100 g b. w. for a week caused a 25 % increase in oxygen consumption. Further enlargement of the T4 dose had little additive effect. In the dose range 20–80 μg T4/100 g b. w., no important changes occurred in lactate production or glucose consumption. Only at the highest T4 dose did the glucose consumption increase significantly. The most profound effect of T4 was on lipolysis. A daily dose of 20 μg T4/100 g b. w. gave a doubling of glycerol production rate, the maximum occurring at a dose of 40 μg T4/100 g b. w Inactivation of the nervous system was without influence on the T4-induced increase in oxygen consumption. However, the T4-induced elevation of lipolysis disappeared after abolition of the nervous activity. This raises the possibility that the T4 effect on lipolysis in skeletal muscle is a potentiation of catecholamine effects. The T4-induced oxygen consumption increase might be dependent not on the lipolytic process but rather on other energy-consuming cell processes.
LACK OF ACUTE EFFECT OF TRIIODOTHYRONINE ON NORADRENALINE RESPONSES OF ISOLATED SYMPATHECTOMIZED CAT HEARTS
Authors: Wahlberg Peter , Carlsson Enar , Brandt Ulla
Published: December 2008

The effect of 3–5–3′-triiodothyronine (T3) on chronotropic and inotropic responses to noradrenaline (NA) was studied on isolated heart preparations of cats sympathectomized with 6-OH-dopamine. Heart rates, left ventricular isovolumic pressures (P) and dP/dt were recorded, and concentration dose-response curves to NA were constructed. In the test series, T3 (0.01 and 0.1 μg per ml) was added to the perfusion medium. T3 did not affect the form nor the position of these curves. The results indicate that T3 does not have an acute effect on NA responses of sympathectomized isolated cat hearts, nor does it have inotropic or chronotropic effects of its own in these experimental conditions.
RADIOIMMUNOASSAY FOR PORCINE LIPOTROPHIC PEPTIDE B
Authors: Neureuther G. , Schwandt P. , Otto J.
Published: December 2008

A sensitive radioimmunoassay for the lipolytic peptide B from pig pituitary glands has been developed. Antisera were raised in rabbits, which allowed a final dilution of 1:6000. Free and antibody bound [125I]peptide B could be separated by double antibody, by dextran-coated charcoal and by polyethyleneglycol. The smallest detectable amount was 0.5 ng/ml. Peptide B could be measured irregularly in porcine sera; there was crossreacting material in an extract of a total human pituitary gland, but not in human sera. The assay seems specific except for a strong cross-reaction with porcine neurophysin. There are indications that peptide B consists of neurophysin and a small lipolytically active peptide which remains to be further characterized.
OESTROGENIC ACTIVITY OF OESTRADIOL-DECANOATE AFTER ORAL ADMINISTRATION TO RODENTS
Authors: de Visser J. , van der Vies J.
Published: December 2008

Oestradiol-decanoate, dissolved in arachis oil and orally administered to rodents, produces oestrogenic effects. Compared on a molecular basis the ester has 0.1–1.0 times the activity of ethinyl oestradiol, dependent on the species and the parameter studied.

The effects of oestradiol-decanoate are less or absent when the oil is omitted. It is likely that absorption of the steroid ester takes place via the intestinal lymphatics in conjunction with the oil.
NON-SUPPRESSIBLE INSULIN-LIKE ACTIVITY DURING ACUTE METABOLIC AND ENDOCRINE CHANGES IN DOGS
Authors: Eigenmann J. E. , Francke-Mäder M. , Zapf J. , Froesch E. R.
Published: December 2008

Non-suppressible insulin-like activity (NSILA-S) was determined in dogs after acute changes in the blood sugar and after injection of growth hormone. Serum was chromatographed over Sephadex G-50 columns equilibrated in 1 m acetic acid and NSILA-S was determined in the fractions between 55 and 85 % column volume using a protein binding assay and the conventional fat pad assay. The results obtained with these two methods correlated rather well (r = 0.74). Hyperglycaemia induced by an intravenous glucose load, by intravenous administration of mannoheptulose or both was not followed by an increase in NSILA-S levels. The injection of insulin and human growth hormone did not lead to alterations of the NSILA-S levels. It is concluded that total NSILA-S levels in the dog do not change acutely following manipulations of the blood sugar and that, in all likelihood, NSILA-S plays no role in the regulation of blood glucose.
LACK OF EFFECT OF PROLACTIN INHIBITION BY ALPHA-BROMOERGOCRIPTINE (CB 154) ON PLASMA ALDOSTERONE IN ANEPHRIC AND NON-NEPHRECTOMIZED PATIENTS ON REGULAR HAEMODIALYSIS
Authors: Ølgaard K. , Hagen C. , Madsen S. , Hummer L.
Published: December 2008

To investigate whether a direct influence exists between the prolactin suppressive effect of alpha-bromoergocriptine (CB 154) and the aldosterone response to a potassium stimulation, the present study was performed in 7 anephric patients and in 7 non-nephrectomized patients, all on regular haemodialysis. The increase in the plasma potassium concentration between dialysis was used as a stimulus to the adrenals, and was correlated to the increase in the plasma aldosterone concentration (PAC).

Plasma samples were obtained during a control period and during a corresponding period of treatment with bromocriptine. Despite a significant fall in the prolactin levels during the bromocriptine treatment, no differences in the aldosterone response to the increasing potassium concentration in the two periods were found neither in the anephric nor in the non-nephrectomized patients.

It is concluded that depression of prolactin levels by the dopamine agonist (bromocriptine) has no influence on the ability of the adrenals to react with an increase in aldosterone secretion following potassium stimulation in dialysis patients with and without preserved renin-angiotensin system.
HYPOTHALAMIC ENDOCRINE DYSFUNCTION IN ANOREXIA NERVOSA
Authors: Aro Antti , Lamberg B.-A. , Pelkonen Risto
Published: December 2008

The hypothalamic-pituitary function of 21 women with anorexia nervosa, aged 15–34 years, was studied. The tests included, in addition to the usual tests of thyroid function, a TRH stimulation test with 200 μg of synthetic TRH given iv; the response of serum immunoreactive growth hormone to insulin; and the diurnal variation and response of plasma cortisol to insulin hypoglycaemia.

The mean serum TSH level of the patients was higher than that of healthy controls. The mean maximal increment of TSH after TRH was similar in the patients and the controls. However, 18 of the patients but none of the controls showed a delayed TSH-response to TRH, i. e. the TSH-level at 60 min was higher than that recorded 20 min after TRH. Four of the patients had a low free thyroxine index, computed from the PBI and T3 Sephadex uptake values, and 3 of these were clinically hypothyroid. The means for PBI, T4 and the free thyroxine index were all significantly below the means for the controls.

The basal serum growth hormone levels were increased in 9 out of 17 patients. In 4 of these an inadequate response to insulin or to glucagon was found. In 5 out of the 8 patients with normal basal growth hormone levels a normal response was found, whereas the remaining 3 showed a subnormal response. The serum growth hormone level was correlated with the degree of weight loss but not with the serum albumin concentration. Plasma cortisol at 08.00 was increased in 9 patients and the diurnal variation was inadequate in 6. Four patients showed a subnormal response to insulin-induced hypoglycaemia, and 2 out of 5 patients tested failed to show adequate suppression of plasma cortisol after 1 mg of dexamethasone.

Dysfunction of the hypothalamic-pituitary axis is common in anorexia nervosa. A delayed TSH-response to TRH, compatible with hypothalamic dysfunction, seems to be an almost consistent feature of the disorder, and in some of the patients even clinical hypothalamic hypothyroidism may be evident.
DEVELOPMENT OF STRESS-INDUCED PITUITARY PROLACTIN AND TSH RELEASE IN MALE RATS
Authors: Fenske M. , Wuttke W.
Published: December 2008

Blood was collected from male rats of various ages under control conditions and after introduction of two stress factors. All animals were sacrificed between 15.00 and 16.00 h. Serum prolactin levels in immature male rats were found to be very low between birth and day 15 after birth. Neither exposure to a new environment, for example removal from the animal rooms for the duration of 10 min, nor exposure to concentrated ether vapour resulted in increased serum prolactin levels. Between day 20 and 35 basal serum prolactin levels were increased, they then fell at adult values. During this period of increasing serum prolactin levels pituitary prolactin release became stress-susceptable; i. e. elevated serum prolactin levels were observed after introduction of stress factors as in adult male rats. Serum TSH levels were found to be high between birth and day 10. Low TSH levels measured between day 15 and 40 and adult values were detected after day 40. Neither ether nor removal of the animals from their normal environment changed serum TSH levels at any age tested. These results indicate that the hypothalamo-pituitary in immature rats reacts in a similar way as that in adult animals from day 16–20 onwards. Serum TSH levels in these animals, however, are reduced, indicating that an increase in serum TSH is not necessary for normal processes of maturation.
IODOPEPTIDES FROM HUMAN THYROGLOBULIN
Authors: Valenta Lubomir J. , Strosberg A. Donny , Valenta Vera , Jaton Jean-Claude
Published: December 2008

Human thyroglobulin labelled in vivo by 125I was purified from eight different thyroid glands including normal thyroid tissue, thyrotoxic goitre and euthyroid multinodular goitre. The purified protein was cleaved with cyanogen bromide (CNBr) and the resulting peptides were separated by column chromatography and ion exchange chromatography. Reproducible elution profiles of both protein and iodine were obtained. However, the distribution of iodine depended on the iodine content of the intact thyroglobulin. Small CNBr peptides seemed to be preferentially iodinated, but with a limited capacity. With higher degrees of iodination, larger peptides became richer in iodine. This suggests sequential iodination of the thyroglobulin molecule. The mixture of small peptides was digested by trypsin. Two iodopeptides were identified in this material by peptide mapping and they had identical migration in thyroglobulins of different origin. One of them was purified by ion exchange chromatography and high voltage electrophoresis. Analogous amino acid composition was obtained for the iodopeptide purified from two different thyroglobulins. The data indicates that thyroglobulin iodination occurs in specific portions of the polypeptide chain and probably in a sequential manner.
A CASE OF ADRENOGENITAL SYNDROME WITH ABERRANT 11β-HYDROXYLATION
Authors: Maschler I. , Weidenfeld J. , Muller A. , Slavin S. , Shaefer J. , Chowers I. , Finkelstein M.
Published: December 2008

A 17 year old female patient with hypertension, amenorrhoea and hirsutism was found to have subnormal levels of plasma and urinary cortisol, significant plasma levels of Reichstein's compound S and 21-deoxycortisol, high urinary levels of THS and pregnanetriolone as well as elevated levels of plasma and urinary testosterone. Treatment with 0.5 mg/day of dexamethasone or 25 mg/day cortisone reduced her hypertension and restored her menstrual cycles, but also resulted in the development of moon face, body striae and a gain in weight. Lower doses of cortisone were without effect. The deficient cortisol production coupled with the presence of unusual intermediates such as Reichstein's compound S and 21-deoxycortisol can be explained by a shift in the substrate specificity of 11β-hydroxylase from C-21-hydroxylated substrates (i.e. compound S) to C-21-deoxy substrates (i.e. 17-hydroxyprogesterone).
OVARIAN HCG-BINDING CAPACITY DURING THE OESTROUS CYCLE OF THE RAT
Authors: Siebers J. W. , Peters F. , Engel W.
Published: December 2008

Binding of 125I-labelled HCG to rat ovary varies during the oestrous cycle. The highest amount of binding was found in dioestrous-II rats (7.33 × 10−15 mol of HCG per mg wet weight), while the lowest binding was observed in oestrous rats (1.67 × 10−15 mol of HCG per mg wet weight). An inverse correlation exists between the binding capacity of the ovary and the concentration of circulating LH. It is concluded that the low binding capacity of the rat ovary in the oestrous stage is due to masking of the specific receptors by the excessively high LH hormone secretion in pro-oestrus.
THE REGULATORY FUNCTION OF A PITUITARY LH-RH-DEGRADING ENZYME SYSTEM IN THE FEEDBACK CONTROL OF GONADOTROPHINS
Authors: Kuhl Herbert , Rosniatowski Christian , Taubert Hans-Dieter
Published: December 2008

It had previously been shown that a luteinizing hormone-releasing hormone (LH-RH)-inactivating enzyme in the rat hypothalamus, L-cystine arylamidase, is in all probability involved in the short-loop feedback mechanism of LH. Since this enzyme system was also shown to be present in the pituitary, the effect of the iv injection of several sex hormones upon its activity was investigated.

The basal arylamidase activity was found to be considerably higher in the neurohypophysis as compared to the adenohypophysis. The injection of 10 μg LH brought about a significant rise in arylamidase activity (+60 %) only in the latter. There was a dose-dependent increase in the pituitary enzyme activity 2 h after the iv administration of LH, and 16 h after the injection of oestradiol and progesterone into dioestrous rats.

Contrary to previous findings obtained with hypothalamic homogenates, the effect of LH upon the enzyme in the pituitary proved to be not dependent on the presence of sex steroids, as the iv application of 10 μg LH into ovariectomized rats resulted in an increase of pituitary L-cystine arylamidase by about 30 %. The injection of testosterone, oestradiol and - to a lesser degree - progesterone into adult male rats caused a significant increase of enzyme activity in the hypophysis. Progesterone proved to be ineffective in the hypothalamus.

This indicates that in contrast to the hypothalamus there is no sex-specific response of the LH-RH-degrading enzyme in the pituitary. It is concluded that this enzyme system seems to play an important part in the mechanisms regulating gonadotrophin release in the pituitary.
CHARACTERIZATION OF T3 IMMUNOREACTIVITY RELEASE FROM THYROID GLAND IN VITRO: A REFLECTION OF COLLOID DROPLET FORMATION
Authors: Chatterjee Sadhana , Takaishi Masaru , Shimizu Taeko , Shishiba Yoshimasa
Published: December 2008

T3 immunoreactivity release from the thyroid gland in vitro was shown to be increased by TSH. In the present study, we sought to determine whether the T3 immunoreactivity release is an indicator of thyroid hormone secretion or due to hormone synthesis. When thyroid glands from mice were incubated with TSH, T3 immunoreactivity release was increased in parallel with intracellular colloid droplet formation in a dose related manner. When colchicine, a known inhibitor of colloid droplet formation, was added, both T3 immunoreactivity release and colloid droplet formation were inhibited, whereas MMI, an inhibitor of hormone synthesis, failed to influence both aspects. Thus, T3 immunoreactivity release as a reflection of colloid droplet formation was demonstrated. The analysis of the released immunoreactivity by Sephadex column and subsequent radioimmunoassay suggested that the T3 immunoreactivity was, to a considerable extent, due to macromolecule instead of T3 itself. The effect of I− or Li+ to inhibit thyroid hormone secretion was shown to be on the step prior to, but not subsequent to, colloid droplet formation.
THE EFFECT OF STREPTOZOTOCIN-INDUCED DIABETES ON THE PITUITARY-THYROID AXIS IN GOITROGEN-TREATED RATS
Authors: Pericás Isabel , Jolín Trinidad
Published: December 2008

Studies of pituitary and thyroid function have been carried out in normal (intact) and diabetic Wistar rats. Diabetes was induced by a single streptozotocin injection (7 mg/100 g body weight). The animals were fed a low iodine diet (LID), and received a daily sc injection of either KClO4 (20 mg/100 g body weight) or propylthiouracil (PTU) (1.5 mg/100 g body weight) to induce hypothyroidism. Control groups received the same LID but supplemented with 0.8 μg I/g dry weight.

In intact rats goitrogen-treatment induces an increase in thyroid weight and in plasma TSH concentration. However, the plasma TSH response to goitrogen-treatment in diabetics indicates that pituitary TSH secretion increases following a reduction in plasma PBI, but the response is less marked than in controls. The difference in plasma TSH between control and diabetic rats provides an explanation for the findings that diabetes diminishes the thyroid growth response to goitrogen-treatment. Moreover, in intact rats the low pituitary TSH content is a consequence of the increase in pituitary TSH secretion, while in the diabetics the low pituitary TSH content cannot be explained by an increase in TSH secretion. The effect of diabetes on the pituitary-thyroid axis cannot be attributed specifically to poor growth, because the changes in pituitary-thyroid function which are observed in the diabetic groups are not seen in intact rats with a growth rate similar to that of insulin deficient rats.

Insulin administration to goitrogen-treated diabetic rats results in 1) an increase in the ability of the thyroid tissue to respond to its trophic hormone, 2) an increase in pituitary TSH secretion in response to the lowering of plasma PBI and, 3) an increase in thyroid growth response to goitrogen-treatment. Results are discussed in relation to the assumption that the lack of adequate insulin levels, or its metabolic defects, diminishes the full response of the thyroid to TSH, and affects the pituitary TSH secretion probably as a consequence of altered hypothalamic control of the pituitary function.
SERUM CALCITONIN IN HYPERGASTRINAEMIA DUE TO ACHLORHYDRIA
Authors: Fahrenkrug Jan , de Muckadell Ove B. Schaffalitzky , Rehfeld Jens F.
Published: December 2008

The serum concentrations of immunoreactive gastrin and immunoreactive calcitonin were measured in 13 fasting patients with achlorhydria and pernicious anaemia and in 10 age- and sex-matched fasting control subjects. All patients had highly elevated concentrations of gastrin in serum (1486 ± 336 pg/ml, mean ± sem). The mean concentration in the controls was 35.2 ± 6.4 pg/ml. No difference in the concentration of calcitonin was found between the pernicious anaemia patients and the controls, the levels being 0.93 ± 0.08 and 0.89 ± 0.03 ng/ml, respectively. Suppression of endogenous gastrin secretion in 5 of the patients by intragastric acid administration was not accompanied by any decrease in calcitonin concentration in serum.

The findings suggest that chronically elevated endogenous gastrin is without influence on calcitonin secretion.
THE SERUM LEVELS OF PROGESTERONE AND 20α-DIHYDROPROGESTERONE, AND THE OVARIAN LH, FSH AND PRL BINDING DURING LUTEOLYSIS OF THE SUPERLUTEINIZED RAT OVARY
Authors: Torjesen Peter A. , Aakvaag Asbjørn
Published: December 2008

The process of luteolysis has been studied in immature rats in which superluteinization had been induced with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotrophin (HCG). Following prostaglandin F2α and the prostaglandin analogues, and at the end of the pseudopregnancy, the plasma levels of progesterone and 20α-dihydroprogesterone were measured and used as parameters of luteal function in relation to the capacity of the ovarian tissue to bind LH, FSH and prolactin (PRL) in vitro. On day 19 after HCG a marked decrease in the progesterone level from the day 8 level was observed concomitant with a marked increase in 20α-dihydroprogesterone. The capacity of the ovarian tissue to bind LH in vitro was markedly reduced on day 19 compared to day 8. Identical changes were observed 21 h after 1 mg prostaglandin F2α or prostaglandin analogues. Progesterone decreased from about 600 ng/ml to about 50 ng/ml, whereas the increase in 20α-dihydroprogesterone was from about 200 ng/ml to 500–1000 ng/ml and the reduction in LH binding sites was from 1.7 × 10−12 to 0.5 × 10−12 mol/mg protein. Nanogram amounts of the analogues were as effective as 1 mg of prostaglandin F2α. The number of FSH or PRL binding sites was not affected by spontaneous luteolysis or the treatment given.

By the use of graded doses of the prostaglandin analogues a negative correlation (r=−0.81) was found between plasma progesterone and 20α-dihydroprogesterone levels, and a positive correlation (r = 0.84) between LH binding sites and plasma progesterone levels.

The luteolysis induced by prostaglandin F2α or prostaglandin analogues was indistinguishable from the spontaneous luteolysis using these parameters.
EVALUATION OF PROPRANOLOL-GLUCAGON TEST
Authors: Okada Y. , Watanabe K. , Takeuchi T. , Hata T. , Mikam H. , Brown F. A. , Kumahara Y.
Published: December 2008

A propranolol-glucagon test was evaluated in 24 control normal children, 21 pituitary dwarfs, 15 patients with constitutional short stature, 2 with chromosome aberration and 4 with miscellaneous diseases. The dose of glucagon enough for the stimulation of human growth hormone (HGH) secretion is more than 20 μg/kg of body weight. During the test in the control subjects the serum HGH level increased from 2.3 ± 1.2 ng/ml to a maximum level of 30.0 ± 15.1 ng/ml, when 10 mg propranolol, regardless of body weight and 30 μg glucagon per kg of body weight are given. The dose of propranolol administered ranged from 0.2 to 1.0 mg/kg of body weight in normal children studied. Serum 11-OHCS also increased significantly from 14.5 ± 11.2 μg/100 ml to 30.1 ± 15.5 μg/100 ml (P <0.01). There was no difference in the maximum level of urinary total catecholamines in propranolol-glucagon test between 7 pituitary dwarfs and 7 control subjects. The mechanism of HGH response to propranolol-glucagon administration is unknown, but propranolol-glucagon administration is a sensitive and reliable provocative test for HGH secretion, since false negative responses of HGH are not observed in patients with non-pituitary disease.
LACK OF A CIRCANNUAL CYCLE OF DAYTIME SERUM PROLACTIN IN MAN AND MONKEY
Authors: Gala Richard R. , Van De Walle Cynthia , Hoffman William H. , Lawson David M. , Pieper David R. , Smith Stuart W. , Subramanian Marappa G.
Published: December 2008

Serum samples were obtained from 7 subjects (6 men and 1 woman) in the morning (09.00 h) and in the afternoon (15.00 h) of each week for a period of 13 months and assayed for prolactin by RIA. In addition, 4 female monkeys were sampled once weekly in the afternoon for approximately two years. The data were analyzed for cyclicity by power spectrum analysis. In both species a serum prolactin circannual cycle was not obvious. In most subjects statstically significant (P<0.05) cycles were observed; however, there was considerable variability among individuals in the duration of the cycle, which ranged between 4 and 50 weeks. A similar result was also observed for the monkey data; here the cycles ranged between 7 and 51 weeks. The physiologic significance of these cycles is unknown at present. It is suggested that although there appears to be no diurnal serum prolactin circannual cycle, this does not rule out the possibility that there may be a nocturnal circannual cycle.
FAILURE OF SODIUM LOADING OR DEFICIENCY TO AFFECT PLASMA PROLACTIN IN THE MALE RAT
Authors: Mattheij J. A. M.
Published: December 2008

The relation between plasma prolactin (PRL) and sodium metabolism was studied in adult male rats. During the experiments attention was given to the avoidance of stress. Cannulated rats were infused with 2.5 ml 5 % NaCl over a 40 min period. Plasma PRL did not change during or up to 2 h after this infusion. Other rats were subjected to a sodium deficient diet for 3 weeks. This treatment which induced a marked rise in plasma aldosterone, did not cause a change in plasma PRL. It is concluded that PRL does not have an important role in the regulation of sodium balance.
INFLUENCE OF INDOMETHACIN AND OF POLYPHLORETIN PHOSPHATE FRACTIONS ON IN VIVO SECRETION OF THYROID HORMONE IN MICE
Authors: Melander A. , Westgren U. , Ingbar S. H.
Published: December 2008

Previous in vivo studies in mice have shown that polyphloretin phosphate (PPP), a polyionic polyester of phosphoric acid and the dihydrochalcone phloretin, can inhibit thyroid hormone secretion induced by TSH and by the long-acting thyroid stimulator of Graves' disease (LATS), but not that induced by catecholamines or 5-hydroxytryptamine (5-HT). The present study was undertaken to explore further the mechanism of this effect, particularly the possibility that PPP interferes with the synthesis of endogenous prostaglandins (PG). Therefore, the effects of PPP and some of its subfractions and congeners were compared with those of indomethacin, a known inhibitor of PG synthesis, with respect to their influence on the blood radioiodine (BRI) increase in response to TSH, 5-HT, and isoprenaline (IPNE) in 125I- and T4-pre-treated mice.

When given alone, neither indomethacin nor PPP or its subfractions reduced the BRI levels. Instead, small increments were seen in occasional experiments. Indomethacin did not inhibit the BRI increase in response to any of the thyroid-stimulating agents, but rather enhanced the responses in occasional experiments. PPP and some of its high-molecular weight subfractions reduced the BRI increases in response to TSH but not those to 5-HT or IPNE. The findings do not support the concept that de novo synthetized PG mediates TSH activation of thyroid hormone secretion, but they favour the view that PPP inhibits the action of TSH at its receptor site.
A RADIOLIGAND RECEPTORASSAY FOR SERUM HCG
Authors: Brand Egenius C. , Kassenaar A. A. H. , van Hall E. V.
Published: December 2008

A radioligand receptorassay system is described for the measurement of human choriogonadotrophin (HCG) in serum, using 600–1600 × g fractions of homogenates of superovulating rat ovaries. The method is specific for HCG and lutrophin (LH), with a detection limit of 3.5 mIU HCG. The values obtained in the dilutions of pregnancy sera paralleled the standard curve up to 20 μ1, and no non-specific effects were found with this amount of serum.

The potency ratio R/I, measured in normal pregnancy sera by radioligand receptorassay and radioimmunoassay, varied between 1.1 and 3.2. No relationship was found between the stage of pregnancy and the R/I ratio.