Serum levels of growth hormone during the stunted postnatal development of the vasopressin-deficient Brattleboro rat

1983 ◽  
Vol 98 (3) ◽  
pp. 351-356 ◽  
Author(s):  
G. J. Boer ◽  
M. Rieutort
Keyword(s):  
Growth Hormone ◽  
Postnatal Development ◽  
Serum Levels ◽  
Postnatal Growth ◽  
The Body ◽  
Rapid Decline ◽  
Brattleboro Rats ◽  
Brattleboro Rat ◽  
Gh Secretion ◽  
Constant Period

Levels of GH in serum were assayed during the development of heterozygous (HET) control and vasopressin-deficient homozygous (HOM) Brattleboro rats. In early postnatal growth no differences in GH concentrations were present between HET and HOM rats for the rapid decline in serum levels of GH in the first week and the constant period up to day 24 of age thereafter. However, higher values were found in 55-day-old HOM rats and lower values at the age of 9 months. It is concluded that the stunted development of the body and brain of HOM rats is not GH-related, and that changes or anomalies in GH secretion appear only after neurogenesis has been completed.

Disturbances of growth hormone-insulin-like growth factor axis and response to growth hormone in acidosis

1998 ◽  
Vol 275 (1) ◽  
pp. R120-R128
Author(s):  
Karina Jandziszak ◽  
Carlos Suarez ◽  
Ethan Wasserman ◽  
Ross Clark ◽  
Bonnie Baker ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Food Intake ◽  
Linear Growth ◽  
Growth Failure ◽  
Serum Levels ◽  
Igf Binding Proteins ◽  
Gh Secretion ◽  
Term Administration ◽  
Igf Binding ◽  
Final Length

Severe chronic metabolic acidosis (CMA) in rats is associated with poor food intake and downregulation of growth hormone (GH), insulin-like growth factors (IGFs), and liver receptors; the administration of recombinant GH (rGH) fails to improve the growth failure. In mice with carbonic anhydrase II deficiency (CAD), a model of moderate CMA with food intake close to normal, we studied serum levels of GH, IGFs, and IGF-binding proteins, and the growth response to rGH. CAD was associated with low serum levels of GH in males. Randomized administration of rGH from ∼5 to ∼12 wk to CAD mice improved food efficiency and increased serum IGF-I levels, final length, and weight compared with placebo without affecting blood pH. Although administration of rGH also increased linear growth in healthy animals, the effect was less than that in CAD mice and was only observed when started before 6 wk of life. Thus growth failure in CAD mice is associated with a decrease in GH secretion in males but not in females. Long-term administration of rGH increases linear growth in CAD mice despite persistent CMA.

scholarly journals Specific Involvement of Gonadal Hormones in the Functional Maturation of Growth Hormone Releasing Hormone (GHRH) Neurons

Endocrinology ◽  
2010 ◽  
Vol 151 (12) ◽  
pp. 5762-5774 ◽  
Author(s):  
Laurie-Anne Gouty-Colomer ◽  
Pierre-François Méry ◽  
Emilie Storme ◽  
Elodie Gavois ◽  
Iain C. Robinson ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Postnatal Development ◽  
Potassium Current ◽  
Hormonal Treatment ◽  
Gonadal Hormones ◽  
Detailed Knowledge ◽  
Releasing Hormone ◽  
Electrophysiological Properties ◽  
Gh Secretion ◽  
Voltage Dependent

Growth hormone (GH) is the key hormone involved in the regulation of growth and metabolism, two functions that are highly modulated during infancy. GH secretion, controlled mainly by GH releasing hormone (GHRH), has a characteristic pattern during postnatal development that results in peaks of blood concentration at birth and puberty. A detailed knowledge of the electrophysiology of the GHRH neurons is necessary to understand the mechanisms regulating postnatal GH secretion. Here, we describe the unique postnatal development of the electrophysiological properties of GHRH neurons and their regulation by gonadal hormones. Using GHRH-eGFP mice, we demonstrate that already at birth, GHRH neurons receive numerous synaptic inputs and fire large and fast action potentials (APs), consistent with effective GH secretion. Concomitant with the GH secretion peak occurring at puberty, these neurons display modifications of synaptic input properties, decrease in AP duration, and increase in a transient voltage-dependant potassium current. Furthermore, the modulation of both the AP duration and voltage-dependent potassium current are specifically controlled by gonadal hormones because gonadectomy prevented the maturation of these active properties and hormonal treatment restored it. Thus, GHRH neurons undergo specific developmental modulations of their electrical properties over the first six postnatal weeks, in accordance with hormonal demand. Our results highlight the importance of the interaction between the somatotrope and gonadotrope axes during the establishment of adapted neuroendocrine functions.

Thermal regulatory dysfunction of growth hormone in classical heat stroke?

1996 ◽  
Vol 134 (6) ◽  
pp. 727-730
Author(s):  
Abdulaziz Alzeer ◽  
Abdullah Al Arifi ◽  
Mohsen El-Hazmi ◽  
Arjumand S Warsy ◽  
Eric S Nylen
Keyword(s):  
Growth Hormone ◽  
Core Temperature ◽  
Heat Stroke ◽  
The Body ◽  
Body Core Temperature ◽  
Treatment Unit ◽  
Gh Secretion ◽  
Body Core ◽  
Time Of Admission ◽  
Regulatory Dysfunction

Alzeer A, Al Arifi A, El-Hazmi M, Warsy AS, Nylen ES. Thermal regulatory dysfunction of growth hormone in classical heat stroke? Eur J Endocrinol 1996;134:727–30. ISSN 0804–4643 Growth hormone (GH) secretion associated with classical (non-exertional) heat stroke (HS) was evaluated in 26 HS victims and 10 control (non heat-exhausted) subjects during the annual Hajj in Makkah, Saudi Arabia. On admission to the HS treatment unit, the GH level was 1.54 ± 0.14 ng/ml (approximately 3.5-fold higher in the HS victims compared to controls; p = 0.005). The GH levels subsequently declined by 78% by 24 h. The categorized GH response was significantly associated with survival for those subjects with a GH level of < 5.53 ng/ml by 6 h (chi-squared test; p = 0.06). In those patients who died (N = 6), there was a continued increase in GH levels from the time of admission, which peaked at 6 h. In those patients who survived, the GH levels peaked at the time of admission and declined rapidly thereafter. There was a direct correlation of age and GH level upon admission (p = 0.02), as well as to peak GH (p = 0.041). However, there was no relationship of GH level to either body core temperature or the cooling time. In summary, HS induced significant GH secretion. The degree of GH response was not related to the body core temperature and was more pronounced in older individuals and in those that died. Although patients with GH deficiency and HS are characterized by anhidrosis/hypohidrosis, there does not appear to be dysfunction of GH response to heat stress-associated HS. In contrast, a vigorous GH response at 6 h suggested a worse outcome. ES Nylen, Rm GE 246, VAMC, 50 Irving St, NW Washington, DC 20422, USA

scholarly journals Differential Response to Aminergic Stimuli and Biological Behavior of Growth Hormone Secreting Pituitary Adenomas

1990 ◽  
Vol 17 (1) ◽  
pp. 78-82 ◽  
Author(s):  
Guillermo Fanghanel ◽  
Oscar Larraza ◽  
Martha Villalobos ◽  
Leticia Fanghanel ◽  
Marcos Velasco ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Growth Hormone ◽  
Oral Dose ◽  
Single Oral Dose ◽  
Clinical Course ◽  
Serum Levels ◽  
Biological Behavior ◽  
Treatment Results ◽  
Gh Secretion ◽  
Aggressive Tumor

ABSTRACT:Growth hormone (GH) serum levels in response to the administration of aminergic drugs and thyroliberine (TRH) were determined in a group of 34 acromegalics. Administration of bromocriptine (10 mg single oral dose) was followed by a decrease in GH below 60% control values in 35% of the cases. Administration of diazepam (10 mg single oral dose) to those cases not responding to bromocriptine induced a decrease in GH in 58% of the cases and an increase in GH in 42%. Administration of cyproheptadine (24 mg/day for one month) to those cases not responding to bromocriptine or with increased GH after the administration of diazepam, decreased GH in 75%, while increased GH in 25% of the cases. TRH 200 (Xg single I.V. dose induced increase of 128% GH basal level in 65% of cases (TRH positive) which correlated with more benign clinical course, decreased GH levels in response to bromocriptine, increased PRL levels, PRL-GH mixed secreting adenomas in immunohistochemistry studies, presence of granulated cells in electron microscopy studies and normalization of GH in the majority of surgically treated cases. By contrast, TRH negative cells correlated with aggressive tumor growth, lack of response to bromocriptine, normal PRL levels, pure GH secreting adenomas by immunohistochemistry, poorly granulated cells and lack of response to surgical treatment. Results suggest that there is more than one type of acromegaly that might be distinguished by the aminergic control on GH secretion.

Effects of long-term treatment with growth hormone-releasing peptide-2 in the GHRH knockout mouse

2005 ◽  
Vol 289 (5) ◽  
pp. E762-E767 ◽  
Author(s):  
Maria Alba ◽  
Danilo Fintini ◽  
Cyril Y. Bowers ◽  
A. F. Parlow ◽  
Roberto Salvatori
Keyword(s):  
Growth Hormone ◽  
Cell Mass ◽  
Total Body Weight ◽  
Term Treatment ◽  
The Body ◽  
Ghrelin Receptor ◽  
Gh Secretion ◽  
Long Term Treatment ◽  
Total Body

Growth hormone (GH) secretagogues (GHS) stimulate GH secretion in vivo in humans and in animals. They act on the ghrelin receptor, expressed in both the hypothalamus and the pituitary. It is unknown whether GHSs act predominantly by increasing the release of hypothalamic GH-releasing hormone (GHRH) or by acting directly on the somatotroph cells. We studied whether a potent GHS could stimulate growth in the absence of endogenous GHRH. To this end, we used GHRH knockout (GHRH-KO) mice. These animals have proportionate dwarfism due to severe GH deficiency (GHD) and pituitary hypoplasia due to reduced somatotroph cell mass. We treated male GHRH-KO mice for 6 wk (from week 1 to week 7 of age) with GH-releasing peptide-2 (GHRP-2, 10 μg sc twice a day). Chronic treatment with GHRP-2 failed to stimulate somatotroph cell proliferation and GH secretion and to promote longitudinal growth. GHRP-2-treated mice showed an increase in total body weight compared with placebo-treated animals, due to worsening of the body composition alterations typical of GHD animals. These data demonstrate that GHRP-2 failed to reverse the severe GHD caused by lack of GHRH.

Growth hormone receptor deficiency results in blunted ghrelin feeding response, obesity, and hypolipidemia in mice

2006 ◽  
Vol 290 (2) ◽  
pp. E317-E325 ◽  
Author(s):  
Emil Egecioglu ◽  
Mikael Bjursell ◽  
Anna Ljungberg ◽  
Suzanne L. Dickson ◽  
John J. Kopchick ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Food Intake ◽  
Growth Hormone Receptor ◽  
Hdl Cholesterol ◽  
Serum Levels ◽  
High Plasma ◽  
Littermate Control ◽  
Apo B ◽  
Gh Secretion ◽  
Increase Food Intake

We have previously shown that growth hormone (GH) overexpression in the brain increased food intake, accompanied with increased hypothalamic agouti-related protein (AgRP) expression. Ghrelin, which stimulates both appetite and GH secretion, was injected intracerebroventricularly to GHR−/− and littermate control (+/+) mice to determine whether ghrelin's acute effects on appetite are dependent on GHR signaling. GHR−/− mice were also analyzed with respect to serum levels of lipoproteins, apolipoprotein (apo)B, leptin, glucose, and insulin as well as body composition. Central injection of ghrelin into the third dorsal ventricle increased food consumption in +/+ mice, whereas no change was observed in GHR−/− mice. After ghrelin injection, AgRP mRNA expression in the hypothalamus was higher in +/+ littermates than in GHR−/− mice, indicating a possible importance of AgRP in the GHR-mediated effect of ghrelin. Compared with controls, GHR−/− mice had increased food intake, leptin levels, and total and intra-abdominal fat mass per body weight and deceased lean mass. Moreover, serum levels of triglycerides, LDL and HDL cholesterol, and apoB, as well as glucose and insulin levels were lower in the GHR−/− mice. In summary, ghrelin's acute central action to increase food intake requires functionally intact GHR signaling. Long-term GHR deficiency in mice is associated with high plasma leptin levels, obesity, and increased food intake but a marked decrease in all lipoprotein fractions.

Regulation by catecholamines of spontaneous growth hormone secretion in the baboon

1981 ◽  
Vol 241 (3) ◽  
pp. E196-E199
Author(s):  
J. K. Stewart ◽  
D. J. Koerker ◽  
C. J. Goodner ◽  
C. C. Gale ◽  
M. F. Minton ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Serum Levels ◽  
Adolescent Male ◽  
Serum Prolactin ◽  
Base Line ◽  
Spontaneous Growth ◽  
Fourfold Increase ◽  
Gh Secretion

To gain an increased understanding of the role of central neurotransmitters in the regulation of spontaneous growth hormone (GH) secretion in the primate, we investigated the effects of peripheral intravenous infusion of the alpha-adrenergic receptor-blocking agent, phentolamine (5.0-mg bolus and 1.5 mg . kg-1 . 12 h-1), and the tyrosine hydroxylase inhibitor, alpha-methyl-p-tyrosine (MPT, 300 mg . kg-1 . 24 h-1), on the pattern of GH secretion in five adolescent male baboons. Serum GH concentrations were measured in blood samples taken at 20-min intervals over 12 h (0530–1730) after an overnight fast. In nontreatment control studies, GH secretion exhibited a predictable rhythmic oscillation with a mean period of 5.7 +/- 0.4 (SE) h. Phentolamine significantly decreased the 12-h mean and integrated GH concentrations compared to control values, but the small peaks of GH, which could be distinguished from base-line concentrations in three of the animals, occurred at the same time as during control studies. Whereas alpha-methyl-p-tyrosine slightly reduced serum levels of GH, it significantly increased the GH pulse frequency in the baboons. A two- to fourfold increase in serum prolactin levels occurred in all animals treated with MPT. These findings suggest that alpha-adrenergic pathways play a stimulatory role in maintaining spontaneous daytime GH secretion in the baboon and that one or more catecholamines are involved in the generation of rhythmic GH release.

Genetic defects causing functional and structural isolated growth hormone deficiency

2011 ◽  
Vol 2 (2) ◽  
Author(s):  
Vibor Petkovic ◽  
Primus Mullis
Keyword(s):  
Growth Hormone ◽  
Short Stature ◽  
Somatic Growth ◽  
Human Growth ◽  
Postnatal Growth ◽  
Metabolic Effects ◽  
Hormone Deficiency ◽  
Height Velocity ◽  
Gh Secretion ◽  
Normal Standards

AbstractNormal somatic growth requires the integrated function of many of the hormonal, metabolic, and other growth factors involved in the hypothalamo-pituitary-somatotrope axis. Human growth hormone (hGH) causes a variety of physiological and metabolic effects in humans and its pivotal role in postnatal growth is undisputed. Disturbances that occur during this process often cause subnormal GH secretion and/or subnormal GH sensitivity/responsiveness resulting in short stature. Despite the complexity of this linear growth process, the growth pattern of children, if evaluated in the context of normal standards, is rather predictable. Children presenting with short stature (i.e out of normal standards) are treated with daily injections of recombinant human GH (rhGH), which leads in almost all cases to an increase of height velocity. Although it is becoming more and more evident that many genes are involved in controlling the regulation of growth, the main aim of this review is to focus on the GH-1 gene, the various gene alterations and their important physiological and pathophysiological role in growth.

Effects of Seasonality and Fasting on the Body Mass and Plasma Growth Hormone Concentrations of the Raccoon Dog (Nyctereutes procyonoides) and the Blue Fox (Alopex lagopus)

2001 ◽  
Vol 56 (5-6) ◽  
pp. 437-443 ◽  
Author(s):  
Anne-Mari Mustonen ◽  
Petteri Nieminen ◽  
Heikki Hyvärinen ◽  
Juha Asikainen
Keyword(s):  
Growth Hormone ◽  
Body Mass ◽  
The Body ◽  
Nyctereutes Procyonoides ◽  
Raccoon Dog ◽  
Alopex Lagopus ◽  
Gh Secretion ◽  
Blue Fox ◽  
Inadequate Nutrition ◽  
Raccoon Dogs

Growth hormone (G H ) promotes growth and endochondral ossification, but it is also important in the response to fasting due to its effects of increasing gluconeogenesis and lipolysis. In this study eleven raccoon dogs and blue foxes were followed for six months and their body mass and GH levels were measured. In November half of the animals of both species were put to a three-week fast. There were no significant differences in the GH levels between the animals of different ages and the subadults and adults both had quite low GH levels in the summer. Fasting had no effect on the GH levels of the raccoon dogs, but the fasting blue foxes had lower GH concentrations than the controls in Nov 16th. The control blue foxes experienced a significant increase in the GH levels in early November and the fasting blue foxes in late November. The GH concentrations of all the raccoon dogs rose in early December. As fasting did not cause an elevation in the GH levels but the concentrations increased with decreasing temperature and shortening daylength, the autumnal GH secretion of these species could be regulated by endogenous seasonal rhythms entrained by exogenous Zeitgebers such as temperature or photoperiod. The autumnal increase of GH levels contributes to the response to fasting as an adaptation to survive the winter months with inadequate nutrition. The raccoon dog which spends the coldest part of the winter in winter sleep seems to be better adapted to a total fast than the actively wintering blue fox.

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