bluuebunny/crossref_metadata_2025 huggingface dataset:
HYPOTHALAMO‐PITUITARY‐GONADAL FUNCTION IN MALE CENTRAL PRECOCIOUS PUBERTY
Authors: CHAUSSAIN J. L. , SAVAGE M. O. , NAHOUL K. , BRIJAWI A. , CANLORBE P. , JOB J. C.
Published: March 2008

Eleven boys aged 1–10 years with central precocious puberty were studied. According to the pubertal development six were classified as P2, one as P3 and four as P5. In all cases plasma testosterone levels were definitely elevated (1.7–5.8 ng/ml) when compared with pre‐pubertal controls. Peak values after HCG (3 × 1500 u) in four of the boys were in the high adult range. The binding capacity of serum testosterone oestradiol binding globuline (TeBG) ranged between 0.5 and 7.30 μg/dl. Basal plasma levels of LH and FSH were respectively 2.06 ± 0.64 and 1.2 ± 0.25 miu/ml, and peak levels after LHRH (0.1 mg/m2) 13.9 ±3.7 and 2.6 ± 0.43 miu/ml respectively. The data demonstrated a significant increase of plasma testosterone and post LHRH LH peak levels in boys with central precocious puberty when compared with pre‐pubertal controls. The patients at stage P2 exhibited high levels of plasma testosterone contrasting with the degree of pubertal maturation, high values of TeBG and low responses to LHRH which were in the pre‐pubertal range. These findings suggest that the testicular sensitivity to LH increases early in boys with central precocious puberty, while the testosterone responsiveness, both, at peripheral and hypothalamic levels, is delayed.
THE TURNOVER TIME OF CALCIUM IN THE EXCHANGEABLE POOLS OF BONE IN MAN AND THE LONG‐TERM EFFECT OF A PARATHYROID HORMONE FRAGMENT
Authors: REEVE J.
Published: March 2008

(1) A non‐compartmental method is described for analysing the kinetics of the exchange of calcium between the bloodstream and the exchangeable bone pools. (2) This method has been applied to studies on osteoporotic patients treated with low doses of an active fragment of human parathyroid hormone. The data of Phang et al. (1969), who studied the effects of dietary calcium peturbation on normal volunteers, were also analysed. (3) It was found that in response to chronic PTH treatment the transit time of calcium in the exchangeable pools decreased. This could not be explained by the observed changes in the calcium accretion rate to the fixed bone pools, and it was necessary to postulate an alteration in the ratio of the rate constants governing the interchange of calcium between bloodstream and exchangeable pools. (4) The changes in the behaviour of the exchangeable pools in response to dietary perturbation could not be explained by the postulated increase in endogenous PTH secretion rate in response to dietary calcium restriction.
HUMAN THYROID ADENYLATE CYCLASE IN NON‐TOXIC GOITRE: SENSITIVITY TO TSH, FLUORIDE AND THYROID STIMULATING IMMUNOGLOBULINS
Authors: BECH KARINE , MADSEN STIG NISTRUP
Published: March 2008

Homogenates prepared from human thyroid tissue obtained at operation for non‐toxic goitre were separated by differential centrifugation into 1000 g, 5000 g, 10,000 g and 37,000 g fractions. The fractions showed varying amounts of TSH (12.5 mu/ml) and fluoride (10 mmol/1) sensitive adenylate cyclase activity. The 5000 g pellet contained the highest amount of TSH‐sensitive adenylate cyclase activity calculated per mg protein. Of other potential activators tested only fluoride, immunoglobulins from patients with Graves' disease and adrenaline (10−6 mol/l) caused significant stimulation in this fraction, which was selected for further studies.

Maximal activation of adenylate cyclase was obtained with 75 mu TSH/ml incubate, half maximal stimulation with 2.9 mu TSH/ml and detectable stimulation was found with 0.0125 mu TSH/ml. Supramaximal concentrations (1.25 u/ml) gave a decreased response. Stimulation with TSH resulted in a linear production of cyclic AMP for 40–60 min dependent on the TSH concentration. 30 min pre‐incubation of homogenate with TSH at 4°C did not influence the response after addition of ATP‐buffer and subsequent incubation at 37°C, suggesting a very rapid equilibrium for binding of TSH to its receptor after addition of ATP‐buffer to the system.

In the 5000 g fraction stimulation of adenylate cyclase with TSH 12.5–75 mu/ml incubate exceeded that obtained with fluoride, and when combined in maximal concentrations an additive effect was observed after incubation for 40 and 60 min, but not after 10 and 20 min, and fluoride caused a linearization of the cAMP response to maximally stimulatory concentrations of TSH. Thus, fluoride appears to maintain the TSH stimulated adenylate cyclases in a maximally activated state.

The 5000 g fraction was sensitive to stimulation with immunoglobulins (TSI) from ten of eleven randomly selected patients with untreated Graves' disease. TSI stimulated adenylate cyclase activity could exhibit a lag‐phase of at least 20 min, and stimulation was most readily detected after 60 min incubation at 37°C. The TSI preparations from patients with Graves' disease exhibit varying degrees of lag‐phase indicating that TSI is a heterologous class of immunoglobulins with activation kinetics distinctly different from those of TSH.
THE DISAPPEARANCE OF HCG AND RETURN OF PITUITARY FUNCTION AFTER ABORTION
Authors: LÄHTEENMÄKI P.
Published: March 2008

Plasma concentrations of HCG/LH and FSH were monitored after a first trimester abortion in eighteen healthy female volunteers three times weekly until the onset of first menstruation. Plasma concentrations of the HCG were measured with a specific RIA for the beta subunit (β‐sub‐HCG) from the samples of six of these subjects.

The elimination of HCG during the first 12 days was studied from plasma concentrations measured by the radioimmunoassay of LH. The experimental data were well explained by a mathematical model consisting of three exponentially decreasing components. The half‐lives of the two more slowly decreasing components were 27 and 168 h. The estimate of the complete disappearance of HCG was 37.7 days, when the specific (β‐sub‐HCG) assay was used.

Recovery of pituitary function occurred within 4–9 days after abortion, as judged by increased plasma FSH concentrations. In fourteen of eighteen subjects a midcycle LH peak was observed which occurred between 16 and 29 days after abortion. Plasma oestradiol concentrations increased 2–16 days after the rise in plasma FSH. Considerable amounts of HCG still circulated in the blood but the pre‐ovulatory peak of oestradiol never began before HCG/LH concentrations had decreased to below the range of the mid‐cycle LH peak.
GONADOTROPHIN, THYROTROPHIN AND PROLACTIN RESERVE IN β THALASSAEMIA
Authors: LANDAU H. , SPITZ I. M. , CIVIDALLI G. , RACHMILEWITZ E. A.
Published: March 2008

Gonadotrophin (Gn), thyrotrophin (TSH) and prolactin (PRL) reserve was evaluated in patients (aged 12–26 years old) with β thalassaemia. Abnormalities were detected in Gn reserve only. When compared with young adult controls, three of the four female patients and one of the two adult males had markedly impaired Gn responses to LH‐releasing hormone (LHRH). Of the five prepubertal males, one had no Gn rise following LHRH, while responses in the other four patients were comparable to those in boys with delayed puberty. Only one adult male had an exaggerated LH response to LHRH. TSH and PRL dynamics were normal. No correlation could be found between the severity of the disturbance in the gonadal axis and the total number of blood transfusions. Our findings correlate best with the severity of the disease process itself.
BOOK REVIEW
Authors: BAYLISS R. I. S.
Published: March 2008

Book Review in this Article

Recent Advances in Endocrinology and Metabolism. Edited by J. L. H. O'Riordan
ACUTE ENDOCRINE PROFILE OF SULPIRIDE IN THE HUMAN*
Authors: L'HERMITE M. , DENAYER P. , GOLSTEIN J. , VIRASORO E. , VANHAELST L. , COPINSCHI G. , ROBYN C.
Published: March 2008

Normal men and normally menstruating women received i.m. injections of 0.1 to 4.0 mg/kg sulphide. This psychotropic drug induced a very rapid (already significant after 5 minutes) and sustained (still significant after 7 hours) elevation of prolactin (PRL) concentrations in all subjects with no consistent modification of LH and FSH. After injection of 4.0 mg/kg, there was similarly no modification of mean TSH concentrations in the women tested in the luteal phase, as well as of mean GH levels in men. Sulpiride prevented the inhibitory effect on PRL levels of 500 mg levodopa, administered orally simultaneously; levodopa administered 2 hours prior to sulpiride failed to counteract the PRL‐stimulatory effect of sulpiride. Under chronic sulpiride‐induced hyperprolactinaemia, levodopa exhibited however a very slight inhibitory effect on PRL concentrations. These data are in agreement with the hypothesis that sulpiride acts mainly at the pituitary level by blocking dopamine receptors of the lactotropes and support the concept that the menstrual cycle perturbations observed under chronic sulpiride administration result from hyperprolactinaemia itself or from a mechanism quite similar to that by which sulpiride induces hyperprolactinaemia.
AUTOIMMUNE THYROID DISEASE AND THE POLYMYALGIA RHEUMATICA‐GIANT CELL ARTERITIS SYNDROME
Authors: DENT R. G. , EDWARDS O. M.
Published: March 2008

In a study of 250 patients with autoimmune thyroid disease, seven (2.8%) were found to have polymyalgia rheumatica or giant cell arteritis. All cases occurred in female patients over the age of 60 years, a prevalence in this group of 9.3%. No cases of either disorder were seen in a control population of 150 female patients over the age of 50 years attending a cardiac clinic at the same hospital. Awareness of this association may allow earlier diagnosis and treatment of this syndrome in elderly patients with thyroid disease.
UNILATERAL ADRENALECTOMY AND PITUITARY IRRADIATION IN THE TREATMENT OF ACTH‐DEPENDENT CUSHING'S DISEASE IN CHILDREN AND ADOLESCENTS
Authors: LANDAU B. , LEIBA S. , KAUFMAN H. , SERVADIO C. , WAINRACH B.
Published: March 2008

In four juvenile patients with Cushing's disease, the therapeutic approach used was unilateral adrenalectomy followed by irradiation of the pituitary. The follow‐up time of these patients has ranged from 1.5 to 10 years. All four are clinically well. Concentrations of adrenal steroids are within normal limits and they require no additional medication. It is felt that this method gives young patients the chance for normal growth and pubertal development as well as a normal social life, so important in the stressful adolescent years, thus avoiding the handicap incurred by bilateral adrenalectomy and the consequent requirement for continuous substitution therapy.
PITUITARY‐GONADAL FUNCTION IN XYY AND XXY MEN IDENTIFIED IN A POPULATION SURVEY
Authors: SCHIAVI RAUL C. , OWEN DAVID , FOGEL MARVIN , WHITE DANIEL , SZECHTER RENATA
Published: March 2008

Evidence on pituitary‐gonadal function in XYY subjects has been inconclusive and based, for the most part, on selected samples such as institutionalized individuals or subjects examined for particular behavioural or medical characteristics. We report the results of a double‐blind hormonal study of a sample from an entire well‐defined birth cohort of men. The starting population included all males born in Copenhagen during the period 1944–1947 comprising 31,436 individuals. Chromosome determinations conducted on 4139 men representing the top 15.9% of the height distribution of the sample identified 12 XYY and 16 XXY men. All the XYY subjects and 14 XXYs consented to participate in an individual case study and were individually matched to XY controls selected from the total sample. The XYY men had significantly higher plasma concentrations of LH, FSH and testosterone than matched XY controls. There were no differences in testicular size and in the reported number of children between the XYYs and control group. XXY men from the same population showed significantly higher LH and FSH, lower concentrations of testosterone, had smaller testes and reported fewer children than their matched controls.
EFFECT OF ACUTE MYOCARDIAL INFARCTION ON PITUITARY‐TESTICULAR FUNCTION
Authors: WANG CHRISTINA , CHAN VIVIAN , TSE T. F. , YEUNG ROSE T. T.
Published: March 2008

The effect of acute myocardial infarction on the secretions of LH, FSH and testosterone was studied in thirteen male patients. Plasma testosterone fell transiently on the fourth day after acute myocardial infarction. This was accompanied by a rise in LH on the same day which persisted for a week after infarction. Serum FSH showed no significant change. The data suggest that following the medical stress of myocardial infarction, testosterone concentration was suppressed resulting in a compensatory rise in LH.
THE EFFECT OF α ADRENERGIC RECEPTOR BLOCKADE ON THE GLUCAGON‐INDUCED GROWTH HORMONE RESPONSE
Authors: TANAKA T. , SUWA S.
Published: March 2008

The effect of a a adrenergic blockade (phentolamine) on glucagon‐induced growth hormone response was tested in five normal men. There was no significant difference in growth hormone concentrations between the glucagon test and the glucagon‐phentolamine test (mean maximum level, 23.4 ± 3.7 ng/ml and 23.1 ± 5.9 ng/ml, respectively). Insulin secretion was significantly higher (P < 0.025) 30 and 60 min after an injection of glucagon in the glucagon‐phentolamine test. The results suggest that the stimulation of growth hormone secretion by glucagon is not mediated through an a adrenergic mechanism.
PHARMACOKINETICS OF 1‐DESAMINO‐8‐D‐ARGININE VASOPRESSIN (DDAVP) IN PATIENTS WITH CENTRAL DIABETES INSIPIDUS
Authors: PULLAN P. T. , BURGER H. G. , JOHNSTON C. I.
Published: March 2008

The pharmacokinetic parameters and biological duration of action of DDAVP were measured in five patients with central diabetes insipidus of differing severity. Plasma half‐life correlated significantly with the duration of action (r= 0.89, P < 0.05), but there was no correlation between the severity of diabetes insipidus and either plasma half‐life or duration of action of DDAVP.
GLUCOSE‐INDUCED INSULIN SECRETION IN PATIENTS WITH PARATHYROID DISORDERS
Authors: HAGUE R. V. , CULLEN D. R. , MARTIN T. J.
Published: March 2008

Glucose‐induced insulin secretion was studied in ten patients with primary hyperparathyroidism and two with idiopathic hypoparathyroidism both before and after treatment. In each individual, insulin secretion during an intravenous glucose tolerance test was greater when the plasma calcium was higher. No consistent change in insulin secretion with plasma calcium concentration was observed during an oral glucose tolerance test. These findings could be explained by the suggestion that insulin secretion provoked by orally adminstered glucose is enhanced by gut hormones which may stimulate insulin secretion by a mechanism independent of extracellular calcium.
MEASUREMENT OF GONADOTROPHINS, TESTOSTERONE, Δ4 ANDROSTENEDIONE AND DIHYDROTESTERONE IN IDIOPATHIC OLIGOSPERMIA
Authors: ROULIER R. , MATTEI A. , DUVIVIER J. , FRANCHIMONT P.
Published: March 2008

Basal concentrations of FSH, LH, testosterone, Δ4 androstenedione and dihydrotestosterone, together with FSH and LH responses to single injections of LHRH were determined in eighty‐four patients with oligospermia and in twenty‐seven normal men. LHRH responses were heterogeneous and indicate that various disorders might cause this syndrome. In six cases there appeared to be an isolated deficiency in spermatogenesis, as indicated by an increased FSH response, whilst the LH response was normal as were the concentrations of the testicular hormones. In twenty cases a concomitant disorder of Leydig cell function and spermatogenesis is suggested as indicated by increased FSH and LH responses and decreased concentrations of testosterone and Δ4 androstenedione (six) or concentrations at the lower limit of normal (fourteen).

Furthermore, in five cases a hypothalamic and/or pituitary disturbance may be accepted on the basis of normal or decreased basal concentrations decreased and responses to LHRH with decreased concentrations of testosterone and Δ4 androstenedione.

Finally, in thirty‐seven cases, oligospermia was not associated with any modification basal gonadotrophin concentrations or response to LHRH when compared with normal subjects.
THE HYPERCALCIURIA OF DIABETES MELLITUS: ITS AMELIORATION WITH INSULIN
Authors: RASKIN PHILIP , STEVENSON MURIEL R. M. , BARILLA DONALD E. , PAK CHARLES Y. C.
Published: March 2008

Calcium and phosphous metabolism was investigated in 20 patients with diabetes mellitus when their diabetes was under poor metabolic control and again once optimal glycaemic control was achieved with aggressive insulin therapy. Ten of the twenty uncontrolled diabetics had hypercalciuria; insulin therapy returned calcium excretion to normal in five. Twenty‐four hour calcium excretion fell in all but two patients when optimal diabetic control was achieved and calcium excretion was positively correlated with glucose excretion. Urinary cyclic AMP excretion, which was in the high normal range during poor control, decreased significantly during optimal insulin therapy. These data suggest that the hypercalciuria of uncontrolled diabetes may be a form of renal hypercalciuria which could result in parathyroid stimulation which might contribute to the development of osteopenia in patients with diabetes mellitus.
THE RELATIONSHIP BETWEEN CIRCADIAN VARIATIONS IN CIRCULATING THYROTROPHIN, THYROID HORMONES AND PROLACTIN
Authors: CHAN VIVIAN , JONES ANN , LIENDO‐CH P. , McNEILLY A. , LANDON J. , BESSER G. M.
Published: March 2008

Half‐hourly blood samples were taken from six clinically euthyroid men over a continuous period of 24 h. Their concentrations of total thyroxine (T4), total triiodothyronine (T3), thyrotrophin (TSH) and prolactin (PRL) were assessed together with the degree of unsaturation of thyroid hormone binding proteins as determined by the thyroid hormone uptake test (THUT). Both T3 and T4 were also measured in urine samples collected serially during the same 24 h period. Significant circadian changes in serum TSH, THUT, serum and urine T4 and serum PRL were demonstrated in all subjects. TSH showed a reciprocal pattern to serum T4, with higher levels during the evening and at night than the daytime. This TSH pattern did not coincide with PRL secretion. Further studies on the same subjects did not show any significant effect of posture, corticosteroid or T4 administration upon circadian changes in TSH. There appeared to be no consistent circadian changes in serum or urinary T3. It seems likely that the TSH circadian rhythm is centrally determined and that free T3 levels are maintained more or less constant by variation in peripheral conversion from T4.
PRELIMINARY STUDIES WITH THE SENSITIVE CYTOCHEMICAL ASSAY FOR PARATHYROID HORMONE
Authors: FENTON S. , SOMERS S. , HEATH D. A.
Published: March 2008

A modification of the cytochemical assay for parathyroid hormone (PTH) is described which permits the measurement of as little as 0.1 fg ml‐1. Using this assay circulating concentrations in normal humans range between 1 and 30 pg ml‐1 using a bovine PTH standard. Elevated values are found in hyperparathyroidism with reduced concentrations in hypoparathyroidism. Where detectable, PTH concentrations measured by radioimmunoassay are on average fourteen‐fold higher than by cytochemical assay. No cross reactivity was found with AVP, calcitonin and 1,25 dihydroxy vitamin D in concentrations normally found in health or disease.
HYPERPROLACTINAEMIA AND IMPOTENCE
Authors: FRANKS S. , JACOBS H. S. , MARTIN N. , NABARRO J. D. N.
Published: March 2008

Clinical, laboratory and radiological findings were evaluated in twenty‐nine men who had raised serum prolactin concentrations and pituitary tumours. Twenty‐one had functionless pituitary tumours (‘prolactinomas’) and eight had acromegaly. Suprasellar extension was detected in twenty of the twenty‐six men who had lumbar airencephalography. Three patients were studied before, sixteen before and after and ten only after pituitary ablative therapy.

Seventeen of these men complained of complete lack of libido and impotence and six had impaired libido and sexual potency; only six patients in this series denied reproductive symptoms. Thirteen of the impotent subjects had small soft testes, ten reduced facial and body hair and three had marked gynaecomastia. No features of hypogonadism were noted in the six patients without reproductive symptoms and none of the patients had galactorrhoea.

Serum prolactin concentrations were higher and serum testosterone concentrations lower in the impotent men compared with those with normal sexual potency. Serum LH and FSH (both basal and in response to LHRH), oestradiol and oestrone concentrations were not different between the two groups and, except in those with post‐operative hypopituitarism, were within the normal range. Following successful lowering of prolactin concentrations by surgery or bromocriptine or both, serum testosterone rose and potency returned; by contrast failure to lower prolactin concentrations was associated with persistent impotence and hypogonadism.

The endocrine profile of low serum testosterone concentrations with gonado‐ trophins which had not risen into the range usually seen in primary hypogonadism (together with the parallel increase of LH and testosterone in one patient studied sequentially during treatment which suppressed prolactin levels to normal), suggested that the impaired gonadal function was caused by a prolactin‐mediated disturbance of hypothalamic‐pituitary function.
ULTRASTRUCTURAL AND STEROIDOGENIC CHARACTERISTICS OF AN ANDROGEN‐PRODUCING ADRENOCORTICAL TUMOUR
Authors: HUHTANIEMI I. , KAHRI A. I. , PELKONEN R. , SALMENPERÄ M. , SIVULA A. , VIHKO R.
Published: March 2008

A 16‐year‐old female patient with an adrenal tumour was studied. Clinically she had progressive hirsutism, showed high urinary 17‐oxosteroid excretion with normal plasma cortisol. Plasma C19‐steroids, both unconjugated (including testosterone) and sulphate‐conjugated, were greatly elevated. On surgical exploration an adrenal tumour and the adjoining adrenal were removed; the tumour was histologically an adenoma. On ultrastructural analysis the cells in all zones of the adjoining adrenal were considered normal. Although the tumour cells had the general appearance of a steroid‐secreting cell their structure diverged from the cells of every subzone of the cortex. This was the case particularly with mitochondria and lipid inclusions. The only endogenous unconjugated steroids detected in the adjoining cortex were corticosterone and cortisol while in tumour tissue these were present in lesser amounts. The tumour tissue contained large amounts of C19‐steroids, 11β‐hydroxy‐andro‐stenedione being quantitatively most significant. On the basis of the steroid profile an impaired defect of 21‐hydroxylation in tumour cells leading steroid synthesis from corticosteroidogenesis to the C19 pathway is proposed.
INSULIN INFUSION INTO THE PORTAL AND PERIPHERAL CIRCULATIONS OF UNANAESTHETIZED DOGS
Authors: STEVENSON R. W. , PARSONS J. A. , ALBERTI K. G. M. M.
Published: March 2008

Changes in glucose, phosphate, potassium, non‐esterified fatty acids (NEFA) and insulin in peripheral venous blood were compared in five unrestrained fasted dogs during different rates of insulin infusion by the portal and peripheral circulation. The‘low’rate of insulin infusion was that required to produce a fall in plasma glucose of 0.56–0.83 mmol/l (0.024 u/kg/h ♀, 0.012 u/kg/h ♂). Two‐fold and fourfold higher rates are referred to as‘medium’and‘high’rates, respectively. In all dogs, dose‐related reductions in the glucose concentration of peripheral blood resulted from increasing the rate of insulin by either route. At‘low’and‘high’rates of infusion the net response was independent of the route of administration, but the‘medium’rate of insulin infusion led to a greater degree of hypoglycaemia when given peripherally than intraportally. As expected, insulin infused peripherally resulted in graded increases in peripheral insulin levels as the rate of infusion was increased from low to high while, paradoxically, intraportal administration at low and medium infusion rates resulted in a mean decrease of peripheral insulin levels from control, the low‐dose producing the most consistent fall. The fact that hypoglycaemia accompanied this fall during portal infusion suggests that these low doses of insulin had a direct effect on glucose metabolism in the liver. This hepatic action appears to be overwhelmed by peripheral uptake of glucose at the high rates of insulin infusion. A qualitatively different effect on plasma phosphate resulting from the change in route of administration of insulin (i.e. increase during portal and decrease during peripheral infusion) also suggests a direct hepatic effect of insulin given intraportally.
SIMULTANEOUS STUDY OF CORTISOL, GROWTH HORMONE AND PROLACTIN NYCTOHEMERAL VARIATIONS IN NORMAL AND OBESE SUBJECTS. INFLUENCE OF PROLONGED FASTING IN OBESITY
Authors: COPINSCHI G. , LAET M.‐H. DE , BRION J. P. , LECLERCQ R. , L'HERMITE M. , ROBYN C. , VIRASORO E. , CAUTER E. VAN
Published: March 2008

Hourly integrated concentrations (IC) of growth hormone (GH), prolactin (PRL) and cortisol were determined by a continuous sampling procedure in six obese women, before and at the end of a 12 day fast, and in eight normal controls under basal conditions. Hormonal 24 h IC and nyctohemeral variations were calculated from these data. Nyctohemeral rhythms were investigated by the periodogram method.

A significant increase over basal values of 24 h IC of PRL, GH and cortisol was observed at the end of the fasting period. Nyctohemeral variations‐but not nyctohemeral rhythm‐of IC‐GH were found in normal subjects. They were abolished in obese patients under basal conditions but restored during fasting. The circadian rhythm of cortisol was not altered in obesity. A shift of the normal nyctohemeral rhythm of PRL was observed in obese patients, but the normal pattern was restored during fasting.
OESTRADIOL SECRETION IN MEN AND PRE‐MENOPAUSAL WOMEN
Authors: LENTON ELIZABETH A. , COOKE I. D. , SAMPSON GWYNETH A. , SEXTON LYNNE
Published: March 2008

Blood samples were obtained from a group of regularlycycling normal women (n = 13) and a group of normal men (n= 5) at 15 min intervals for periods ranging from 9–14 h whilst the subjects remained resting quietly in bed. The concentration of plasma oestradiol was measured in a radioimmunoassay which had been carefully optirnised and the mean concentration and coefficient of variation calculated for each subject.

Plasma oestradiol concentrations were found to fluctuate rapidly in all subjects. The largest sample‐to‐sample variation was found in regularly cycling women near mid‐cycle, and the least variation occurred in the male subjects. The coefficients of variation were approximately twice the intra‐assay variation confirming that the observed pulsatile patterns of secretion were not due to technical errors.

An analysis of variance performed on the mean hourly concentrations from each subject showed a significant variation (P < 0.001) between sampling periods with peaks occurring during the first hour of sampling (08.00–09.00 hours). This result is suggestive of the presence of a circadian rhythm although it is not conclusive.
THYROTROPHIN, PROLACTIN AND GROWTH HORMONE RESPONSES TO TRH IN BARBITURATE COMA AND IN DEPRESSION
Authors: NAEIJE R. , GOLSTEIN J. , BEYL D. ZEGERS DE , LINKOWSKI P. , MENDLEWICZ J. , COPINSCHI G. , BADAWI M. , LECLEKCQ R. , L'HERMITE M. , VANHAELST L.
Published: March 2008

The effects of 200 μg thyrotrophin‐releasing hormone (TRH) i.v. on thyrotrophin (TSH), prolactin (PRL), growth hormone (GH) and triiodothyronine (T3) were studied in eight patients with barbiturate coma due to attempted suicide, in the same patients after recovery, in eight depressive patients and in eight normal controls. The patients with barbiturate coma presented normal basal TSH and PRL, elevated basal GH and normal PRL but blunted TSH responses to TRH; their GH concentrations varied widely without consistent relation to TRH administration. The same patients after recovery from coma presented normal TSH and PRL, slightly elevated basal GH, and normal PRL but blunted TSH responses to TRH; in four of these patients, a clear‐cut rise in GH (i.e. more than 10 ng/ml) occurred after TRH administration. The depressive patients presented normal basal TSH and PRL, slightly elevated basal GH, and normal PRL but blunted TSH responses to TRH; in four of these patients, a moderate rise in GH (less than 10 ng/ml) occurred after TRH administration. The increment in T3 concentrations 120 min after TKH was found reduced in the comatose patients only. Basal cortisol was measured in all the subjects and found elevated in the comatose patients only. It is concluded that the abnormal TSH and GH responses to TRH observed in patients with barbiturate coma are more likely related to depressive illness than to an effect of barbiturates at the pituitary level. Barbiturates might affect thyroid secretion.
ENDOCRINE EFFECTS OF SPIRONOLACTONE IN MAN
Authors: TIDD M. J. , HORTH C. E. , RAMSAY L. E. , SHELTON J. R. , PALMER R. F.
Published: March 2008

A double blind, controlled study was carried out in order to investigate the effects of administering spironolactone, 200 mg daily, to five healthy male volunteers. The patterns of change in plasma testosterone (T) and luteinizing hormone (LH) after spironolactone were significantly different from placebo and there were significant increases in the urinary excretion of androsterone (A), aetiocholanolone (EC) and total oestrogen. Urinary dehydroepiandrosterone (DHA) excretion, after an initial rise, declined progressively during the treatment period relative to controls. The results are discussed in the light of previous observations. It is concluded that treatment with spironolactone for 2–4 days will lead to a transient rise in plasma T and urinary DHA. Continued treatment (4–10 days) is thought to cause increased LH secretion, with normalization of plasma T and DHA excretion. These changes are accompanied by increased androgen catabolism and a slightly increased conversion of androgens to oestrogens. Healthy men may therefore show alterations in sex steroid metabolism if treated for several days with high doses of spironolactone.
NORMAL PROLACTIN RESPONSE FOLLOWING THYROTROPHIN RELEASING HORMONE IN PATIENTS WITH AUTONOMOUSLY FUNCTIONING EUTHYROID MULTINODULAR GOITRE
Authors: ELTE J. W. F. , WIARDA K. S. , FROLICH M. , HAAK A.
Published: March 2008

Twelve female patients (mean age 60 years, range 41–74) with euthyroid multinodular goitre and a flat TRH test (median A TSH 0.9 IU/ml, range 0–3.5) had normal prolactin responses to TRH (median A prolactin 48 ng/ml, range 6–115). The results are comparable with those in euthyroid patients receiving full substitution doses of thyroid hormone without increasing T3 and/or T4 levels beyond the normal range.
FACTORS GOVERNING INSULIN AND GLUCAGON RESPONSES DURING NORMAL MEALS
Authors: DAY JOHN L. , JOHANSEN KLAUS , GANDA OM P. , SOELDNER J. STUART , GLEASON RAY E. , MIDGLEY WENDY
Published: March 2008

An experimental model is described which can be used to study substrate and hormone responses to normal meals administered in very near normal circumstances. After 500, 300 and 125 calorie meals, the relative proportion of fat or protein content did not influence the plasma glucose except for minor differences between the high protein‐high fat meals. The insulin response to such meals was correlated positively with the increment in glucose but reduction of protein content below 8 g caused a significant reduction in the increment in plasma insulin per unit increase in plasma glucose. Alterations in protein content above 8 g made no difference. Fat content of the meal did not significantly alter the insulin response. No evidence was obtained for a major component of insulin release attributable to either bulk or pre‐absorption phenomena such as sight or smell. It is concluded that a significant accentuation of the insulin response to meals is dependent on a minimum amount of protein and that this is probably mediated by one of the gastro‐intestinal hormones. Glucagon release is dependent on protein and carbohydrate content of the meal and is independent of the fat content. There may also be an early stimulation of glucagon release, regardless of content, which may also be hormonally mediated.
EVALUATION OF STEROID LABORATORY TESTS AND ADRENAL GLAND IMAGING WITH RADIOCHOLESTEROL IN THE AETIOLOGICAL DIAGNOSIS OF CUSHING'S SYNDROME
Authors: BARBARINO A. , DE MARINIS L. , LIBERALE I. , MENINI E.
Published: March 2008

Basal values of the urinary excretion of 17‐oxogenic steroids and serum levels of cortisol were not satisfactory in the differentiation of ‘suspected’ subjects from patients with true Cushing's syndrome. With an RIA method for serum cortisol determination, the overnight dexamethasone suppression test provided the most reliable single test in establishing adrenocortical hyperfunction. Thirty‐five normal subjects, fifty‐nine obese patients, thirteen ‘suspected’ patients, and thirteen patients with disease states other than Cushing's syndrome had suppressed values below 4.0 μg/100 ml. None of the ten patients with Cushing's syndrome had a cortisol concentration less than 16.3 μg/100 ml. Adrenal gland scintigraphy after radiocholesterol injection is a more valuable tool than the metyrapone test and the high‐dose dexamethasone suppression test in the localization and differential diagnosis of adrenocortical lesions causing Cushing's syndrome. It obviates the need for angiographic procedure in the localization of adenomas. It is a reliable technique for identifying functioning adrenal remnants. We therefore propose a schedule for studying patients with suspected adrenocortical hyperfunction.
THYROID HORMONE LEVELS DURING GLUCOSE TOLERANCE TEST IN EUTHYROID SUBJECTS
Authors: PREMACHANDRA B. N. , GOSSAIN VED V. , PERLSTEIN I. B.
Published: March 2008

Twelve normal, healthy, clinically and biochemically proven euthyroid volunteer subjects (age 19–35) were administered a standard glucose tolerance test (100 g glucose orally) and thyroxine (T4), triiodothyronine (T3) and reverse tri‐iodothyronine (rT3) levels were determined by specific radioimmunoassays to determine the acute effect of glucose and insulin on peripheral monodeiodination of thyroxine. The fasting levels of T4, T3, rT3 and free thyroxine were 82.4 nmol/l, 1.7 nmol/l, 0.52 nmol/l, and 0.22 nmol/l, respectively, and these levels were unchanged during the 3 hours post‐glucose load. The rise and fall of glucose and insulin levels were typical of the standard responses normally observed in the glucose tolerance test. The variations in insulin and glucose levels were not correlated with thyroid hormone concentrations at any interval during the test. It is therefore concluded that dietary glucose does not acutely cause shifts in peripheral monodeiodination of thyroxine in healthy euthyroid subjects.
SEMINAL IMMUNOREACTIVE PROLACTIN BEFORE AND AFTER VASECTOMY
Authors: LUQMAN W. A. , SMITH M. L.
Published: March 2008

Seminal fluid was assayed for prolactin by radioimmunoassay in eleven healthy males 8–12 weeks following vasectomy. The results were compared with those obtained in 34 age matched subjects prior to undergoing vasectomy. The mean values (± 1 SD) for prolactin were similar (postvasectomy = 11.4 ± 3.2 ng/ml, prevasectomy = 12.7 ± 6.1 ng/ml) and there was no statistically significant difference (t= 0.66, P=> 0.05). This study shows that prolactin is found in secretions of the prostate and/or seminal vesicles.
INDIVIDUAL NEUROPHYSIN CONCENTRATIONS IN THE PITUITARY AND CIRCULATION OF HUMANS
Authors: DAX E. M. , CLAPPISON B. H. , PULLAN P. T. , PEPPERELL R. , JOHNSTON C. I.
Published: March 2008

Specific, homologous human neurophysin I and II radioimmunoassays were established and used to measure the individual, immunoreactive neurophysin concentrations in human plasma. Circulating levels of human neurophysin I in normal individuals were less than 1 ng/ml and neurophysin II levels were 1–2 ng/ml. During dehydration, there was a significant rise in plasma neurophysin I, together with an increase in neurophysin II. Haemorrhage also was associated with a rise in plasma neurophysin I and II, but the percent increase was greater for I than II. In two subjects in whom nicotine inhalation caused a rise in plasma neurophysin I, there was no detectable increase in plasma neurophysin II. These stimuli which have been reported to release vasopressin from the posterior pituitary also are associated with the differential release of neurophysin I. Plasma neurophysin II levels could more clearly be shown to rise independently of plasma neurophysin I during events thought to be related to oxytocin release. Plasma neurophysin II levels were significantly elevated in women taking oral contraceptives. Similarly' during pregnancy there was a progressive rise in plasma neurophysin II concentration which was proportional to the period of gestation. Plasma neurophysin II concentrations in seven of fifteen nursing women rose significantly during suckling. There was no detectable change in plasma neurophysin I concentrations during any of these events. Plasma neurophysin I and II levels were both signficantly elevated in fourteen patients with chronic renal failure and rose over haemodialysis, suggesting that the kidney may be the major route of clearance of the neurophysins. In humans the independent release of neurophysin II was associated with stimuli thought to release oxytocin, but neurophysin I showed only a differential release compared to neurophysin II in vasopressin stimulated events.
THE RELEVANCE OF 25‐HYDROXYCALCIFEROL MEASUREMENTS IN THE TREATMENT OF HYPOPARATHYROIDISM*
Authors: MASON REBECCA S. , POSEN SOLOMON
Published: March 2008

In twenty‐one patients with chronic hypoparathyroidism a close correlation was observed between the prescribed dose of ergocalciferol and mean serum 25‐hydroxy‐calciferol levels. In the 75 serum specimens examined, a significant correlation was found between 25‐hydroxycalciferol levels and calcium concentrations. The measurement of serum 25‐hydroxycalciferol levels is of potential clinical value in the prediction of hyper‐or hypocalcaemic episodes and in monitoring patient compliance.
AUGMENTATION OF PITUITARY THYROTROPHIN RESPONSE TO THYROTROPHIN RELEASING HORMONE DURING SUBPHYSIOLOGICAL TRI‐IODOTHYROININE THERAPY IN HYPOTHYROIDISM
Authors: RIDGWAY E. CHESTER , KOURIDES IONE A. , CHIN WILLIAM W. , COOPER DAVID S. , MALOOF FARAHE
Published: March 2008

Five hypothyroid patients are reported with increased pituitary TSH response to TRH during administration of T3. In one patient treated with intravenous T3, 50 μg daily for 10 days, the peak serum TSH and total pituitary TSH reserve after TRH increased coincident with increases in serum T3 and T4 levels and a decrease in the basal TSH concentration. In four patients treated with oral T3, the peak serum TSH and total pituitary TSH reserve after TRH increased during administration of subphysiological doses of T3. Peak serum T3 levels occurred 4 h after ingestion and increased progressively with increasing T3 doses. Serum TSH levels decreased modestly with the nadir at 4 h after T3 ingestion and then returned to basal levels at 24 h. Augmentation of TSH responses to TRH occurred simultaneously with decreases in serum cholesterol, a swell as increases in the pituitary prolactin response to TRH, and increases in the GH and cortisol response to insulin induced hypoglycaemia where these responses could be studied. These data demonstrated a positive effect of subphysiological T3 therapy in these hypothyroid patients on the TSH response to TRH as well as increases in the responses of other pituitary hormones to stimulation.
PROLACTIN CONCENTRATIONS IN NORMAL MENSTRUAL CYCLES AND CONCEPTION CYCLES
Authors: LENTON ELIZABETH A. , BROOK LINDA M. , SOBOWALE OLADELE , COOKE IAN D.
Published: March 2008

Plasma prolactin concentrations were measured daily throughout twenty‐three menstrual cycles from regularly ovulating women. In five of the cycles conception occurred spontaneously. The frequency distribution of prolactin concentrations was calculated and an appropriate linear transform obtained. Means and 95% confidence limits were determined by inspection of the logarithmic probability plots and these gave mean concentrations (and ranges) of 302 (106–871) mU/1 for the non‐conception cycles and 178 (58–550) mU/1 for the conception cycles. Distribution of prolactin concentrations was log‐normal in all cases, although the population containing the conception cycles was distinct from the population of non‐conception cycles. It is suggested that the normal range found in ovulating women is 80–800 mU/1 but that for conception to occur levels should be slightly lower and approximate to the range 60–600 mU/1. Thus the lower limit of normal is about 60 mU/1 and the upper limit about 800 mU/1. Any concentration over 800 mU/1 should be designated as hyperprolactinaemia.
EFFECT OF HUMAN GROWTH HORMONE THERAPY ON HEAD CIRCUMFERENCE IN CHILDREN WITH HYPOPITUITARISM
Authors: LARON Z. , ROITMAN A. , KAULI R.
Published: March 2008

Head circumference was measured before and during hGH therapy in fourteen children with isolated growth hormone deficiency (IGHD) and in twenty‐one children with multiple pituitary hormone deficiencies (MPHD).

In both groups there was a retardation in growth of the neurocranium, more marked in the children with IGHD, which was less than the retardation in linear height. In the group with IGHD, initiation of hGH therapy before a chronological age of 5 and a bone age of 3 had been reached led to a rapid catch‐up in cranial growth with normalization of the head size. In older children the induction of head growth was similar to that achieved by the long bones but without a true catch‐up phenomenon. In three adults with hereditary IGHD without therapy or with irregular treatment during late puberty, the head circumference was below normal range.

In view of the possible role played by development of brain tissue upon cranial size, the importance of early diagnosis and initiation of therapy in infants and young children with a deficiency of hGH is stressed.
SERUM T3 AND T4 LEVELS IN PATIENTS WITH ANOREXIA NERVOSA SHOWING TRANSIENT HYPERTHYROIDISM DURING WEIGHT GAIN
Authors: MOORE RAY , MILLS IVOR H.
Published: March 2008

Serum thyroxine (T4) and triiodothyronine (T3) levels were measured in a group of thirty‐three patients with anorexia nervosa (AN) and compared with twenty‐five control women presenting with hirsutism and twenty‐one patients with primary myxoedema. T3 levels in the AN patients were significantly lower than in the control subjects and in the patients with myxoedema while T4 levels were significantly higher than in the patients with hypothyroidism but significantly lower than in the control group. Seventeen anorexia patients had further T3 and T4 levels measured following an arbitrary 25% weight gain and both levels had increased significantly. For individual patients, the absolute rise in T3 levels was significantly correlated with the rate of weight gain. Thirteen patients had serial T3 and T4 levels measured during their periods of weight gain. Eight of these subjects showed a gradual rise in T3 levels from subnormal or low normal levels to values in the upper normal range. Four subjects showed a distinct and self limiting overshoot of T3 levels and, associated with this, the patients had clinical features of mild hyperthyroidism.
THE EFFECT OF SOMATOSTATIN ON METABOLIC AND HORMONAL CHANGES DURING AND AFTER EXERCISE
Authors: CHALMERS R. J. , BLOOM S. R. , DUNCAN G. , JOHNSON R. H. , SULAIMAN W. R.
Published: March 2008

The effect of intravenous somatostatin on blood levels of metabolites and hormones has been examined in normal subjects who performed a 30‐minute period of bicycle exercises at 70% maximal exercise capacity. The results have been compared with control studies in the same subjects. Measurements were made of blood levels of lactate, glucose, free fatty acids, glycerol, acetoacetate, 3‐hydroxybutyrate, insulin, glucagon, growth hormone (hGH) and prolactin. Growth hormone and glucagon release were suppressed during exercise with somatostatin and there was a subsequent elevation during recovery. There was slight post‐exercise depression of insulin, but no alteration of plasma prolactin secretion. Blood glucose was reduced during exercise with somatostatin and increased during recovery. The elevation of ketone bodies after exercise was greater in the investigation with somatostatin, but there were no significant changes in other metabolites. Somatostatin, although causing inhibition of hGH release, appeared to have no significant effect upon fatty acid mobilization during exercise.
LONGITUDINAL STUDY OR SERUM THYROID HORMONES, CHORIONIC GONADOTROPHIN AND THYROTROPHIN DURING AND AFTER NORMAL PREGNANCY
Authors: YAMAMOTO TOSHIHIDE , AMINO NOBUYUKI , TANIZAWA OSAMU , DOI KEI , ICHIHARA KIYOSHI , AZUKIZAWA MIZUO , MIYAI KIYOSHI
Published: March 2008

Measurements of serum levels of thyroxine (T4), free T4, 3,5,3′‐triiodothyronine (T3), free T3, 3,3′,5′‐triiodothyronine (reverse T3, rT3), thyroxine‐binding globulin capacity (TBGcap), chorionic gonadotrophin (hCG) and thyrotrophin (TSH) were carried out prospectively in eight women with uncomplicated pregnancies, in order to examine interrelationships between the thyroid gland and thyroid stimulating hormones during pregnancy. During pregnancy the levels of T4, free T4, T3, rT3 and TBGcap were significantly elevated, and TSH was decreased. It was noted that the elevation of T4 was maintained from the 8th to the 27th week of gestation while the level of TBGcap progressively increased. The levels of free T4 and rT3 in the first and third trimesters were significantly higher than those of age‐matched, non‐pregnant women. The levels of hCG showed a biphasic variation, with a peak in the 8th to 15th weeks, followed by a decline in the second trimester and a small, secondary elevation in the 32nd to 39th weeks. This later elevation was positively correlated with changes in free T4 and free T3 levels. The increase of serum T4 accompanied by an increase of free T4 in the first trimester appeared due to augmented secretion of T4, rather than being secondary to the elevated levels of TBGcap.
PROGRESSIVE VISUAL FAILURE IN ACROMEGALY FOLLOWING EXTERNAL PITUITARY IRRADIATION
Authors: ATKINSON A. B. , ALLEN I. V. , GORDON D. S. , HADDEN D. R. , MAGUIRE C. J. F. , TRIMBLE E. R. , LYONS A. R.
Published: March 2008

Four out of twenty‐three acromegalic patients selected for treatment with external megavoltage pituitary irradiation between 1961 and 1975 developed progressive visual failure. They had received megavoltage external irradiation through multiple portals from a cobalt‐60 unit over a period of 3 weeks. Visual deterioration began 2 months to 6 years after irradiation. In two patients the optic nerves were explored. In both, post‐mortem later confirmed radiation damage to the optic nerves and hypothalamus. In one case there was also necrosis of the right frontal lobe with necrosis and inflammation of the bone surrounding the pituitary fossa. In the two other patients, extensive clinical and neuroradiological investigation excluded the presence of a suprasellar mass as a cause for this visual failure and a clinical diagnosis of radiation necrosis was made.