SUPPRESSIVE EFFECT OF L-DOPA ON HUMAN PROLACTIN RELEASE DURING SLEEP

ABSTRACT Immunoreactive plasma human prolactin (HPr) and human growth hormone (HGH) concentrations were measured in six normal young men with polygraphic sleep monitoring during normal sleep and during sleep in which 1-dihydroxyphenylalanine (1-DOPA) was infused intravenously at a rate of 0.8 to 1.0 mg/min. The intravenous infusion of 1-DOPA significantly suppressed the episodic release of HPr during sleep and the occurrence of rapid eye movement (REM) sleep. However, HGH release during sleep was not remarkably influenced by 1-DOPA. These results suggest that central catecholaminergic neural mechanisms are related to both sleep-related HPr release and REM sleep, but do not play an important role in sleep-related HGH release.

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ELISA for Determination of Human Growth Hormone: Recognition of Helix 4 Epitopes

Journal of Biomedicine and Biotechnology ◽

10.1155/s1110724304308090 ◽

2004 ◽

Vol 2004 (3) ◽

pp. 143-149 ◽

Cited By ~ 3

Author(s):

Juliana F. Moura ◽

Luiz DeLacerda ◽

Romolo Sandrini ◽

Fernanda M. Borba ◽

Denise N. Castelo ◽

...

Keyword(s):

Growth Hormone ◽

Human Growth Hormone ◽

Synthetic Peptide ◽

Human Growth ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Immunoaffinity Column ◽

Receptor Dimerization ◽

Human Prolactin

Human growth hormone (hGH) signal transduction initiates with a receptor dimerization in which one molecule binds to the receptor through sites 1 and 2. A sandwich enzyme-linked immunosorbent assay was developed for quantifying hGH molecules that present helix 4 from binding site 1. For this, horse anti-rhGH antibodies were eluted by an immunoaffinity column constituted by sepharose-rhGH. These antibodies were purified through a second column with synthetic peptide correspondent tohGH helix 4, immobilized to sepharose, and used as capture antibodies. Those that did not recognize synthetic peptide were used as a marker antibody. The working range was of 1.95 to 31.25 ng/mL of hGH. The intra-assay coefficient of variation (CV) was between 4.53% and 6.33%, while the interassay CV was between 6.00% and 8.27%. The recovery range was between 96.0% to 103.8%. There was no cross-reactivity with human prolactin. These features show that our assay is an efficient method for the determination of hGH.

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Growth hormone and prostatic tumours: localization using a monoclonal human growth hormone antibody

Journal of Endocrinology ◽

10.1677/joe.0.1030311 ◽

1984 ◽

Vol 103 (3) ◽

pp. 311-315 ◽

Cited By ~ 14

Author(s):

P. E. C Sibley ◽

M. E. Harper ◽

W. B. Peeling ◽

K. Griffiths

Keyword(s):

Growth Hormone ◽

Connective Tissue ◽

Prostatic Carcinoma ◽

Human Growth ◽

Prostatic Hyperplasia ◽

Immunocytochemical Staining ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Immunocytochemical Detection ◽

Human Prolactin

ABSTRACT The immunocytochemical detection of endogenous human GH and the binding of exogenously applied human GH in tumour tissue from patients with benign prostatic hyperplasia or prostatic carcinoma is reported. Monoclonal human GH antibody binding was exclusively to the connective tissue in both benign and carcinomatous specimens. Specificity control experiments indicated that the antibody could be absorbed with human GH but not with human prolactin. Preincubating the sections with human GH considerably altered the immunocytochemical staining, reducing the reaction product within the connective tissue in a concentration-dependent manner and revealing a binding site for GH within the cytoplasm of epithelial cells. J. Endocr. (1984) 103, 311–315

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In Silico Investigation of pH-Dependence of Prolactin and Human Growth Hormone Binding to Human Prolactin Receptor

Communications in Computational Physics ◽

10.4208/cicp.170911.131011s ◽

2013 ◽

Vol 13 (1) ◽

pp. 207-222 ◽

Cited By ~ 9

Author(s):

Lin Wang ◽

Shawn Witham ◽

Zhe Zhang ◽

Lin Li ◽

Michael Hodsdon ◽

...

Keyword(s):

Growth Hormone ◽

Human Growth Hormone ◽

In Silico ◽

Ph Dependence ◽

Prolactin Receptor ◽

Human Growth ◽

Chemical Mechanism ◽

Salt Bridges ◽

Histidine Residues ◽

Human Prolactin

AbstractExperimental data shows that the binding of human prolactin (hPRL) to human prolactin receptor (hPRLr-ECD) is strongly pH-dependent, while the binding of the same receptor to human growth hormone (hGH) is pH-independent. Here we carry in silico analysis of the molecular effects causing such a difference and reveal the role of individual amino acids. It is shown that the computational modeling correctly predicts experimentally determined pKa’s of histidine residues in an unbound state in the majority of the cases and the pH-dependence of the binding free energy. Structural analysis carried in conjunction with calculated pH-dependence of the binding revealed that the main reason for pH-dependence of the binding of hPRL-hPRLr-ECD is a number of salt-bridges across the interface of the complex, while no salt-bridges are formed in the hGH-hPRlr-ECD. Specifically, most of the salt-bridges involve histidine residues and this is the reason for the pH-dependence across a physiological range of pH. The analysis not only revealed the molecular mechanism of the pH-dependence of the hPRL-hPRLr-ECD, but also provided critical insight into the underlying physic-chemical mechanism.

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Disorders of sleep

10.1093/med/9780199568741.003.0054 ◽

2018 ◽

Author(s):

Sophie West

Keyword(s):

Chronic Disease ◽

Eye Movement ◽

Rem Sleep ◽

Excessive Daytime Sleepiness ◽

Slow Wave Sleep ◽

Total Sleep Time ◽

Sleep Time ◽

Sleep Stages ◽

Normal Sleep ◽

Sedative Drugs

Typically, disorders of sleep cause disturbance either to the sufferer or to their bed partner. If total sleep time is reduced, this may lead to problems with excessive daytime sleepiness, which can affect work, driving, concentration, and relationships. ‘Sleepiness’ implies an intrusive desire to fall asleep, caused by some form of sleep deprivation or sedative drugs; this is different from ‘tiredness’, which implies general fatigue, lethargy, and exhaustion and is caused by a range of conditions, including depression, chronic disease, or a busy lifestyle. Adults sleep on average for 8 hours a night. Normal sleep consists of periods of deep or slow-wave sleep, interspersed with shorter periods of dreaming or rapid-eye-movement (REM) sleep. Periods of REM sleep lengthen towards the morning and hence some people remember their dreams on waking. Different disorders of sleep can affect any of these sleep stages.

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PROLACTIN ACTIVITY AND HUMAN GROWTH HORMONE IN PHARYNGEAL HYPOPHYSES FROM EMBALMED CADAVERS

Journal of Endocrinology ◽

10.1677/joe.0.0420205 ◽

1968 ◽

Vol 42 (2) ◽

pp. 205-NP ◽

Cited By ~ 18

Author(s):

PHILOMENA McGRATH

Keyword(s):

Growth Hormone ◽

Functional Significance ◽

Human Growth ◽

Significant Degree ◽

Post Mortem ◽

Adverse Conditions ◽

Total Destruction ◽

Therapeutic Value ◽

Human Prolactin

SUMMARY One hundred and forty-six human pharyngeal hypophyses from embalmed cadavers were fractionated in eight batches. A human prolactin-growth hormone extract was obtained from each batch. The prolactin activity of each extract was tested by the pigeon crop micromethod and the growth hormone content of the same extract was determined by radioimmunoassay. The results indicate that the human prolactin-growth hormone extract of pharyngeal hypophyses from embalmed cadavers retained prolactin activity and growth hormone to a significant degree despite adverse conditions post mortem. It is concluded that the human pharyngeal hypophysis is a tissue of functional significance. The apparent isolation of the pharyngeal hypophysis is of interest with regard to the role of the hypothalamus in the control of the sellar adenohypophysis. The functional significance of the pharyngeal hypophysis may be of importance in subjects for whom the total destruction of adenohypophysial tissue is considered to be of therapeutic value.

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ACUTE SUPPRESSIVE EFFECT OF HUMAN GROWTH HORMONE ON BASAL INSULIN SECRETION IN MAN

Acta Endocrinologica ◽

10.1530/acta.0.0790474 ◽

1975 ◽

Vol 79 (3) ◽

pp. 474-482 ◽

Cited By ~ 5

Author(s):

Ulf Adamson ◽

Erol Cerasi

Keyword(s):

Growth Hormone ◽

Blood Glucose ◽

Human Growth Hormone ◽

Plasma Insulin ◽

Human Growth ◽

Suppressive Effect ◽

Clear Correlation ◽

Basal Plasma ◽

Basal Insulin Secretion ◽

Plasma Insulin Levels

ABSTRACT The acute effects of human growth hormone (GH) on the basal levels of glucose and insulin in blood were investigated in 11 healthy men. GH doses of 5, 10, 20, and 40 μg/kg body weight were given iv as a constantrate infusion over 30 min, and resulted in peak hormone levels (30 min) of 20.5 ± 1.0, 48.5 ± 2.2, 108.2 ± 4.5, and 229.2 ± 14.6 ng/ml, respectively. There was a small (max 9.8 ± 2.6 %) but significant decrease in the blood glucose level, observed already at 15 min after the beginning of the GH infusion and persisting up to 90 min. The highest dose of GH induced the most marked changes, but there was otherwise no clear correlation between dose and effect. The basal plasma insulin levels showed a more marked (max 16.0 ± 4.7 %) decrease which was not correlated, in time or in magnitude, with the changes in blood glucose. In some subjects, in whom no significant decrease in blood glucose was observed, plasma insulin still demonstrated a similar fall (max 20.2 ± 7.6 %). Neither were these changes in plasma insulin correlated to the dose of GH within the range used in this study. The findings suggest that the early, insulin-like effect of GH on blood glucose is distinct from its effect on the pancreas. The latter is a suppressive one, consistent with earlier findings on glucose-induced insulin release.

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