scholarly journals Acromegaly with Normal Basal Growth Hormone Levels

1997 ◽  
Vol 24 (3) ◽  
pp. 250-253 ◽  
Keyword(s):  
Growth Hormone ◽  
Sella Turcica ◽  
Large Mass ◽  
Clinical Feature ◽  
Morphological Transformation ◽  
Gh Secretion ◽  
Mri Scans ◽  
Level Elevation ◽  
Serum Gh ◽  
Ct And Mri

ABSTRACT:Background:The most common cause of acromegaly is excess of growth hormone (GH) secretion.Methods:We report a 42-year-old male patient, who had become acromegalic over the past 5 years. There were no visual changes or change in sexual function, no gynaecomastia or galactorrhoea. Both CT and MRI scans showed a large mass measuring 2.5 x 2.5 x 3.5 cm, originating from the sella turcica and extending into and totally filling up the sphenoid sinus with diffusely invasive features.Results:Basal serum GH level was within normal range, but insulin-like growth factor 1 (IGF-1) was elevated with slightly increased prolactin (PRL) and impaired GH secretory regulation as well. A pituitary adenoma was partially removed through transsphenoidal microsurgery. Pathology confirmed a mammo-somatotrophic adenoma but immunocytochemistry study of the tumour showed only positivity for PRL but not GH.Conclusions:When acromegaly occurs without GH level elevation, one should pay attention that: 1) IGF-1 might be the cause of the clinical feature of acromegaly; 2) The tumour might undergo morphological transformation; and 3) Hyperinsulinemia or GH receptor antibody formation could also be the cause of the acromegalic appearance.

Is there a place for urinary growth hormone measurement?

1993 ◽  
Vol 128 (3) ◽  
pp. 197-201 ◽  
Author(s):  
Maria N Moreira-Andrés ◽  
Francisco J Cañizo ◽  
Federico Hawkins
Keyword(s):  
Growth Hormone ◽  
Screening Method ◽  
Small Sample ◽  
Point Of View ◽  
Intrasubject Variability ◽  
Gh Secretion ◽  
Lack Of Information ◽  
Low Levels ◽  
Plasma Gh ◽  
Serum Gh

The evaluation of growth hormone (GH) secretion is an important problem in pediatric endocrine practice. The diagnosis of GH insufficiency is based on the finding of a "blunted" GH response to GH provocative tests or on the demonstration of a decreased endogenous secretion. From a practical point of view, these methods are uncomfortable, expensive and time consuming. Recently, very sensitive specific assays to measure human GH in urine have been developed. We present a discussion of available data on these tests in order to estimate their role in the evaluation of a short or slowly growing child. The present available assays allow measuring very low levels of GH in a small sample of untreated urine. The main limitations of urinary GH measurement are the intrasubject variability, wide normal range, overlapping results in several GH secretory states and lack of information on GH pulsatility. However, most of these limitations also apply to other tests of GH secretion. The advantage of urinary GH tests is that they provide, in an easy procedure, information on serum GH concentration. There is good correlation between urinary and serum GH concentration and several findings suggest that urinary GH excretion reflects changes in plasma GH levels during the period of urine collection. Therefore, the usefulness of urinary GH measurement is that of a simpler and cheaper screening method for assessing integrated serum GH concentration in clinical practice.

Inhibition of foetal growth hormone (GH) and thyrotrophin (TSH) secretion after maternal administration of somatostatin

1984 ◽  
Vol 106 (3) ◽  
pp. 393-399 ◽  
Author(s):  
Elio Roti ◽  
Giuseppe Robuschi ◽  
Alessandro Alboni ◽  
Rossella Emanuele ◽  
Lorenzo d' Amato ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Cord Blood ◽  
Pregnant Women ◽  
Marked Decrease ◽  
Maternal Blood ◽  
Gh Secretion ◽  
Foetal Growth ◽  
Tsh Secretion ◽  
Maternal Administration ◽  
Serum Gh

Abstract. Somatostatin (SRIF) was infused (500 μg over 30 min) into 68 pregnant women during labour. As a control, saline was infused into 26 pregnant women. Maternal blood was obtained prior to the infusion and at delivery and cord blood was obtained at delivery. The subjects were divided into 4 groups based upon the interval of time from the termination of SRIF infusion and delivery. There was a marked decrease in cord blood thyrotrophin (TSH) from 0 to 180 min and in cord blood growth hormone (GH) from 0 to 120 min following SRIF infusion. SRIF infusion did not affect cord blood iodothyronine and thyroglobulin concentrations. SRIF administration induced a small but significant (P < 0.05) decrease in serum GH concentration but had no other effect on maternal hormone values. These studies strongly suggest that SRIF crosses the human placenta and transiently suppresses foetal anterior pituitary TSH and GH secretion.

scholarly journals Effects of gender on exercise-induced growth hormone release

1999 ◽  
Vol 87 (3) ◽  
pp. 1154-1162 ◽  
Author(s):  
Laurie Wideman ◽  
Judy Y. Weltman ◽  
Niki Shah ◽  
Shannon Story ◽  
Johannes D. Veldhuis ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Area Under The Curve ◽  
Interactive Effects ◽  
Men And Women ◽  
Gh Secretion ◽  
Exercise Condition ◽  
Calculated Mass ◽  
Exercise Induced ◽  
Serum Gh ◽  
Secretion Rates

We examined gender differences in growth hormone (GH) secretion during rest and exercise. Eighteen subjects (9 women and 9 men) were tested on two occasions each [resting condition (R) and exercise condition (Ex)]. Blood was sampled at 10-min intervals from 0600 to 1200 and was assayed for GH by chemiluminescence. At R, women had a 3.69-fold greater mean calculated mass of GH secreted per burst compared with men (5.4 ± 1.0 vs. 1.7 ± 0.4 μg/l, respectively) and higher basal (interpulse) GH secretion rates, which resulted in greater GH production rates and serum GH area under the curve (AUC; 1,107 ± 194 vs. 595 ± 146 μg ⋅ l−1⋅ min, women vs. men; P = 0.04). Compared with R, Ex resulted in greater mean mass of GH secreted per burst, greater mean GH secretory burst amplitude, and greater GH AUC (1,196 ± 211 vs. 506 ± 90 μg ⋅ l−1⋅ min, Ex vs. R, respectivley; P < 0.001). During Ex, women attained maximal serum GH concentrations significantly earlier than men (24 vs. 32 min after initiation of Ex, respectively; P = 0.004). Despite this temporal disparity, both genders had similar maximal serum GH concentrations. The change in AUC (adjusted for unequal baselines) was similar for men and women (593 ± 201 vs. 811 ± 268 μg ⋅ l−1⋅ min), but there were significant gender-by-condition interactive effects on GH secretory burst mass, pulsatile GH production rate, and maximal serum GH concentration. We conclude that, although women exhibit greater absolute GH secretion rates than men both at rest and during exercise, exercise evokes a similar incremental GH response in men and women. Thus the magnitude of the incremental secretory GH response is not gender dependent.

Growth hormone in exercise: comparison of physiological and pharmacological stimuli

1976 ◽  
Vol 41 (4) ◽  
pp. 523-527 ◽  
Author(s):  
J. Sutton ◽  
L. Lazarus
Keyword(s):  
Growth Hormone ◽  
Cycle Ergometer ◽  
Serum Growth Hormone ◽  
Insulin Hypoglycemia ◽  
Arginine Infusion ◽  
Provocative Test ◽  
Gh Secretion ◽  
Ergometer Exercise ◽  
Normal Males ◽  
Serum Gh

This study was designed to compare the serum growth hormone (GH) response with quantified exercise to that obtained with other stimuli. In eight normal males, aged 21–24 yr, we studied the serum GH response to 20 min cycle ergometer exercise at 300, 600, and 900 kpm/min on three separate occasions and compared the results with those found during sleep, insulin hypoglycemia, arginine infusion, and L-DOPA. Exercise at 900 kpm/min and insulin hypoglycemia resulted in the greatest elevations in serum GH which weresignificantly greater than those found with sleep, arginine or L-DOPA. The 20-min exercise at 900 kpm/min represented 75–90% of the subjects' maximal oxygen uptake and is a suitable provocative test for GH secretion. As a screening test for pituitary GH reserve, exercise compares favorably with insulin hypoglycemia and is superior to sleep, arginine, and L-DOPA.

Interaction between the α2-adrenergic system and nursing in the regulation of growth hormone secretion in the neonatal rat

1993 ◽  
Vol 128 (2) ◽  
pp. 184-191 ◽  
Author(s):  
Bálint Kacsóh ◽  
Judith S Opp (Meyers) ◽  
William R Crowley ◽  
Clark E Grosvenor
Keyword(s):  
Growth Hormone ◽  
Neonatal Rat ◽  
Female Rats ◽  
Adrenergic System ◽  
Neonatal Rats ◽  
Humoral Factors ◽  
Adrenergic Agents ◽  
Gh Secretion ◽  
Old Rats ◽  
Serum Gh

Separation of neonatal rats from their mothers decreases, while a subsequent period of suckling (nursing) increases, serum growth hormone (GH) levels in neonatal rats. Milk-borne (humoral) factors and neural factors inherent in mother-offspring interaction have been implicated in these phenomena. Conflicting reports have demonstrated the α2-adrenergic agonist clonidine to increase and to decrease serum GH levels in 10-day-old rats. The present experiments were aimed at testing whether an interaction between the α2-adrenergic system and the nursing-induced changes in GH secretion could account for the discrepancy. Rat pups were treated with clonidine (150 μg/kg) or the α2-adrenergic antagonist yohimbine (10 mg/kg), and the drug treatment was combined with separation of the mothers and nursing. Yohimbine did not affect serum GH levels in separated two-day-old pups (i.e. basal levels of the hormone), but prevented the nursing-induced increase in serum GH concentration. In two-day-old pups, clonidine had no effect on basal GH levels but, like yohimbine, prevented the increase in serum GH normally associated with nursing. Both yohimbine and clonidine prevented active sucking behavior, i.e. the pups did not search for and/or attach to the nipples of their mothers. Moreover, the pups treated with yohimbine and clonidine were cooler to the touch than the littermate controls. In eight-day-old pups, yohimbine prevented the nursing-induced increase in serum GH and decreased GH levels below the saline-injected, separated control. As in two-day-old pups, clonidine prevented the suckling-induced release of GH and failed to induce GH-release above that of saline-injected, separated pups. By day 10 postpartum. clonidine became capable of stimulating GH release, but only in separated male pups. The effects of CLO and nursing in male pups were not additive: either treatment alone was as effective as the combined treatment. In female rats CLO prevented the increase in serum GH levels in response to nursing. It is concluded that (1) the α2-adrenergic agents yohimbine and clonidine inhibit nursing-induced GH secretion in an indirect (perhaps hypothermia-related) manner not involving the well-established α2-adrenergic-GH releasing hormone pathway; (2) the α2-adrenergic system becomes fully functional in terms of stimulation of GH secretion between days 8 and 10; (3) the GH-releasing effects of the α2-adrenergic system are sexually dimorphic in 10-day-old rats.

Synergy ofl-arginine and growth hormone (GH)-releasing peptide-2 on GH release: influence of gender

2000 ◽  
Vol 279 (4) ◽  
pp. R1455-R1466 ◽  
Author(s):  
Laurie Wideman ◽  
Judy Y. Weltman ◽  
James T. Patrie ◽  
C. Y. Bowers ◽  
Niki Shah ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Young Adults ◽  
Stimulus Type ◽  
Follicular Phase ◽  
Analysis Of Covariance ◽  
Gh Secretion ◽  
Basal Serum ◽  
Nested Anova ◽  
Early Follicular Phase ◽  
Serum Gh

We test the hypotheses that 1) growth hormone (GH)-releasing peptide-2 (G) synergizes with l-arginine (A), a compound putatively achieving selective somatostatin withdrawal and 2) gender modulates this synergy on GH secretion. To these ends, 18 young healthy volunteers (9 men and 9 early follicular phase women) each received separate morning intravenous infusions of saline (S) or A (30 g over 30 min) or G (1 μg/kg) or both, in randomly assigned order. Blood was sampled at 10-min intervals for later chemiluminescence assay of serum GH concentrations. Analysis of covariance revealed that the preinjection (basal) serum GH concentrations significantly determined secretagogue responsiveness and that sex ( P = 0.02) and stimulus type ( P < 0.001) determined the slope of this relationship. Nested ANOVA applied to log-transformed measures of GH release showed that gender determines 1) basal rates of GH secretion, 2) the magnitude of the GH secretory response to A, 3) the rapidity of attaining the GH maximum, and 4) the magnitude or fold (but not absolute) elevation in GH secretion above preinjection basal, as driven by the combination of A and G. In contrast, the emergence of the G and A synergy is sex independent. We conclude that gender modulates key facets of basal and A/G-stimulated GH secretion in young adults.

Effect of exogenous growth hormone administration on endogenous growth hormone secretion induced by a met-enkephalin analog

1996 ◽  
Vol 134 (1) ◽  
pp. 73-76 ◽  
Author(s):  
Giuseppe Fanciulli ◽  
Osvaldo Oliva ◽  
Paolo A Tomasi ◽  
Alessandra Pala ◽  
Alba Bertoncelli ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Endogenous Growth ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Inhibitory Effect ◽  
Growth Hormone Administration ◽  
Gh Secretion ◽  
Hormone Administration ◽  
Exogenous Growth ◽  
Serum Gh

Fanciulli G, Oliva O, Tomasi PA. Pala A. Bertoncelli A, Dettori A, Delitala G. Effect of exogenous growth hormone administration on endogenous growth hormone secretion induced by a met-enkephalin analog. Eur J Endocrinol 1996:134:73–6. ISSN 0804–4643 Exogenous growth hormone (hGH) administration in humans attenuates the endogenous growth hormone (GH) response to some pharmacological stimuli: in particular, pretreatment with hGH completely blocks the serum GH response to growth hormone-releasing hormone. In order to evaluate the mechanism(s) whereby opioids induce GH secretion in man, we gave the following treatments to six healthy male volunteers: (a) IV saline: (b) a met-enkephalin analog G-DAMME 250 μg IV as a bolus at time ′: (c) hGH 2 IU as an IV bolus at time −180′; (d) G-DAMME as above, preceded by hGH as above. In our study. G-DAMME stimulated GH secretion both basally (peak 17.9 ± 6.0 ng/ml) and, to a lesser extent, after hGH pretreatment (6.0 ± 2.7 ng/ml). Since in our study G-DAMME was able to partially overcome the inhibitory effect of hGH administration, it is suggested that opioids act through an inhibition of somatostatin release and not through a GHRH-dependent pathway. However, an additional direct effect of hGH on pituitary somatotrophes cannot be excluded. Giuseppe Delitala, Chair of Endocrinology, Viale S. Pietro 12, University of Sassari, 07100 Sassari. Italy

Circulating growth hormone forms in Type 1 diabetic subjects: comparison with normal subjects and acromegalics

1986 ◽  
Vol 112 (4) ◽  
pp. 547-551 ◽  
Author(s):  
L. A. MacFarlane ◽  
Susan Stafford ◽  
A. D. Wright
Keyword(s):  
Growth Hormone ◽  
Normal Subjects ◽  
Molecular Forms ◽  
Diabetic Patients ◽  
Strongly Correlated ◽  
Gh Secretion ◽  
Main Component ◽  
Type 1 Diabetic Patients ◽  
Serum Gh

Abstract. The molecular forms of growth hormone (GH) in serum from 18 Type 1 diabetic patients with poor metabolic control were analysed using sephadex G-100 chromatography. The profiles obtained were compared with those from normal subjects whose GH secretion was stimulated by exercise and hypoglycaemia and eight acromegalic patients. In the three groups three distinct GH forms were found: little (monomeric), big and big-big-GH. Samples from normal subjects contained 45% little-GH which was less than samples from the diabetics and acromegalics (53% and 65%, respectively, P <0.01). Further samples from normal subjects after the onset of hypoglycaemia showed an increase in little-GH. In the three groups, the higher the proportion of little-GH, the lower the proportion of big-big-GH, while the proportion of big-GH remained similar. In the acromegalics the proportion of little-GH was strongly correlated with the log concentration of serum GH. As little-GH is cleared from the circulation quicker than the larger forms these data indicate that the main component of the frequent surges of GH secretion in poorly controlled Type 1 diabetic subjects is little-GH (monomeric forms). The sustained release of GH found in acromegaly is composed largely of monomeric forms.

scholarly journals Acetylcholine Modulates the Hormones of the Growth Hormone/Insulinlike Growth Factor-1 Axis During Development in Mice

Endocrinology ◽  
2018 ◽  
Vol 159 (4) ◽  
pp. 1844-1859 ◽  
Author(s):  
Marie-José Lecomte ◽  
Chloé Bertolus ◽  
Nélina Ramanantsoa ◽  
Françoise Saurini ◽  
Jacques Callebert ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Gastrointestinal Hormone ◽  
Stimulatory Action ◽  
Somatotropic Axis ◽  
Newborn Mice ◽  
Gh Secretion ◽  
Insulinlike Growth Factor ◽  
Main Components ◽  
Serum Gh

Abstract Pituitary growth hormone (GH) and insulinlike growth factor (IGF)-1 are anabolic hormones whose physiological roles are particularly important during development. The activity of the GH/IGF-1 axis is controlled by complex neuroendocrine systems including two hypothalamic neuropeptides, GH-releasing hormone (GHRH) and somatostatin (SRIF), and a gastrointestinal hormone, ghrelin. The neurotransmitter acetylcholine (ACh) is involved in tuning GH secretion, and its GH-stimulatory action has mainly been shown in adults but is not clearly documented during development. ACh, together with these hormones and their receptors, is expressed before birth, and somatotroph cells are already responsive to GHRH, SRIF, and ghrelin. We thus hypothesized that ACh could contribute to the modulation of the main components of the somatotropic axis during development. In this study, we generated a choline acetyltransferase knockout mouse line and showed that heterozygous mice display a transient deficit in ACh from embryonic day 18.5 to postnatal day 10, and they recover normal ACh levels from the second postnatal week. This developmental ACh deficiency had no major impact on weight gain and cardiorespiratory status of newborn mice. Using this mouse model, we found that endogenous ACh levels determined the concentrations of circulating GH and IGF-1 at embryonic and postnatal stages. In particular, serum GH level was correlated with brain ACh content. ACh also modulated the levels of GHRH and SRIF in the hypothalamus and ghrelin in the stomach, and it affected the levels of these hormones in the circulation. This study identifies ACh as a potential regulator of the somatotropic axis during the developmental period.

EFFECT OF AMINOPHYLLINE ON GROWTH HORMONE SECRETION IN MAN

1974 ◽  
Vol 76 (3) ◽  
pp. 488-494 ◽  
Author(s):  
M. Peracchi ◽  
F. Cavagnini ◽  
A. E. Pontiroli ◽  
U. Raggi ◽  
A. Malinverni ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Blood Glucose ◽  
Intravenous Infusion ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Normal Subjects ◽  
Gh Secretion ◽  
Inhibiting Effect ◽  
Plasma Ffa ◽  
Serum Gh

ABSTRACT The effects of intravenously administered aminophylline on growth hormone (GH) secretion have been studied in sixteen normal subjects and four acromegalic patients. Intravenous infusion of theophylline ethylenediamine 480 mg over a 30 min period did not alter the blood glucose and serum GH levels in six normal subjects but raised the plasma FFA by 88 %. By contrast, in four acromegalic patients theophylline administration resulted in a fall of the serum GH levels by 17.6–51.7 %, mean 36.5%. In ten normal subjects the infusion of the drug clearly blunted the GH response to insulin hypoglycaemia without modifying the decrease in blood glucose and plasma FFA induced by insulin: mean peak GH values decreased from 32.7 ± 3.39 to 21.4 ± 4.10 ng/ml (P < 0.025). These data seem to indicate that theophylline has an overall inhibiting effect on the hypothalamic-hypophyseal axis for GH secretion.

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