Growth Hormone (GH) Isoforms Following Acute 22-kDa GH Injection: Is it Useful to Detect GH Abuse?

2004 ◽  
Vol 25 (3) ◽  
pp. 205-208 ◽  
Keyword(s):  
Growth Hormone ◽  
Gh Isoforms

Interassay Differences in Growth Hormone Measurement in Acromegaly

1997 ◽  
Vol 34 (2) ◽  
pp. 156-159 ◽  
Author(s):  
J H Barth ◽  
J H Smith ◽  
P Clarkson
Keyword(s):  
Growth Hormone ◽  
Mean Value ◽  
Consistent Difference ◽  
Plasma Samples ◽  
Plasma Growth Hormone ◽  
Gh Isoforms ◽  
The Mean ◽  
Good Agreement

We measured plasma growth hormone concentrations by three different two-site immunometric assays (Pharmacia hGH RIA, IDS Gamma-BCT and Delfia 22 kDa hGH) to determine whether there are GH isoforms secreted by acromegalic patients that are under-recognized by some assays. There was a fairly good agreement between assays with the IDS Gamma-BCT and Delfia 22 kDa assays giving lower results than the Pharmacia IRMA. GH was measured on stored plasma samples from 24 patients with proven acromegaly. There was a consistent difference between the three assays of approximately 20% of the mean value for each patient.

Unaltered ratio of circulating levels of growth hormone/GH isoforms in adults with Prader–Willi syndrome after GHRH plus arginine administration

2015 ◽  
Vol 25 (4) ◽  
pp. 168-173 ◽  
Author(s):  
A.E. Rigamonti ◽  
G. Grugni ◽  
N. Marazzi ◽  
S. Bini ◽  
M. Bidlingmaier ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Prader Willi Syndrome ◽  
Gh Isoforms ◽  
Circulating Levels

scholarly journals Challenges in Detecting the Abuse of Growth Hormone in Sport

2005 ◽  
Vol 51 (9) ◽  
pp. 1587-1593 ◽  
Author(s):  
Cathy M McHugh ◽  
Roderick T Park ◽  
Peter H Sönksen ◽  
Richard IG Holt
Keyword(s):  
Growth Hormone ◽  
Anabolic Steroids ◽  
Reference Interval ◽  
Naturally Occurring ◽  
Gh Isoforms ◽  
Comprehensive Search ◽  
World Anti Doping Agency ◽  
Academic Interests ◽  
Substances Of Abuse ◽  
Future Concepts

Abstract Background: Growth hormone (GH) is reputed to be in widespread use in the sporting arena as a performance-enhancing agent and is on the list of banned substances published by the World Anti-Doping Agency. The detection of GH abuse poses many challenges. Unlike many substances of abuse, such as synthetic anabolic steroids, GH is a naturally occurring substance; therefore, demonstration of exogenous administration must rely on detecting concentrations in excess of an established reference interval. The purpose of this review is to discuss the methodologies being developed to detect GH abuse. Methods: We undertook a comprehensive search using multiple electronic databases and hand searches of reference lists of articles. The data for this review reflect our academic interests and experience through work on the GH-2000 and GH-2004 projects. Results: Two approaches have been taken to detect GH abuse. The first is based on assessment of the effect of exogenous GH on pituitary GH isoforms, and the second is based on measurement of markers of GH action. The advantages of each approach and the difficulties encountered with each technique, as well as future concepts in detection, are discussed. Conclusion: Although there are substantial challenges for the detection of GH, methodologies now exist to detect GH abuse with reasonable sensitivity and specificity.

scholarly journals Growth hormone (GH) assays: influence of standard preparations, GH isoforms, assay characteristics, and GH-binding protein

1997 ◽  
Vol 43 (6) ◽  
pp. 950-956 ◽  
Author(s):  
Chatarina Jansson ◽  
Cesar Boguszewski ◽  
Sten Rosberg ◽  
Lena Carlsson ◽  
Kerstin Albertsson-Wikland
Keyword(s):  
Growth Hormone ◽  
Cross Reactivity ◽  
Time Resolved ◽  
Conversion Factors ◽  
International Reference ◽  
Gh Isoforms ◽  
Reference Preparation ◽  
Linear And Nonlinear ◽  
Reactivity Study ◽  
The Impact

Abstract The impact of the adoption of the new biosynthetic growth hormone (GH) WHO International Reference Preparation (IRP 88/624), and the recommendation to report results in μg/L instead of mU/L, is described. Conversion factors were determined by comparing both the linear and nonlinear relations of the GH values. The Pharmacia polyclonal IRMA (p-IRMA) and the DELFIA® monoclonal time-resolved immunofluorometric assay (trIFMA) with kit calibrators calibrated either against the pituitary-derived WHO IRP 80/505 or the new 88/624 were evaluated. Conversion factors of 4.17 mU/L = 1 μg/L for the p-IRMA and 4.31 mU/L = 1 μg/L for the trIFMA were necessary. Different cross-reactivity patterns for the deaminated and dimer 22-kDa, 20-kDa, and 17-kDa GH isoforms were found. Expected GH recovery was similar when the measured values were adjusted according to the results of the cross-reactivity study.

The effect of treatment with the oral growth hormone (GH) secretagogue MK-677 on GH isoforms

2003 ◽  
Vol 13 (1) ◽  
pp. 1-7 ◽  
Author(s):  
J. Svensson ◽  
C.L. Boguszewski ◽  
F. Shibata ◽  
B. Carlsson ◽  
L.M.S. Carlsson ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Gh Isoforms ◽  
Effect Of Treatment

22-kD Growth hormone exclusion assay: a new approach to measurement of non-22-kD growth hormone isoforms in human blood

1996 ◽  
Vol 135 (5) ◽  
pp. 573-582 ◽  
Author(s):  
Cesar L Boguszewski ◽  
Lars Hynsjö ◽  
Gudmundur Johannsson ◽  
Bengt-Åke Bengtsson ◽  
Lena MS Carlsson
Keyword(s):  
Growth Hormone ◽  
Human Blood ◽  
Magnetic Beads ◽  
Screening Method ◽  
Physiological Role ◽  
University Hospital ◽  
Serum Samples ◽  
New Approach ◽  
Assay Procedure ◽  
Gh Isoforms

Boguszewski CL, Hynsjö L, Johansson G, Bengtsson B-Å, Carlsson LMS. 22-kD Growth hormone exclusion assay: a new approach to measurement of non-22-kD growth hormone isoforms in human blood. Eur J Endocrinol 1996;135:573–82. ISSN 0804–4643 Human growth hormone (GH) exists in a variety of isoforms. In the pituitary, the most abundant isoform is 22-kD GH (22 K GH), while other isoforms (non-22 K GH) are present in variable amounts. In human plasma, the GH heterogeneity contributes to the wide variability in GH levels measured by different immunoassays. The physiological role of the non-22 K GH isoforms is poorly understood, but they may represent a spectrum of agonists or antagonists of the GH receptor. It is possible that increased amounts of non-22 K GH isoforms in the circulation contribute to the growth failure observed in some short children and may be involved in the pathophysiology of acromegaly and other unrelated diseases. Currently, there is no method available to evaluate the ratio of non-22 K GH isoforms to total GH in large sets of serum samples. In this report, a novel assay procedure is described in which monomeric and dimeric isoforms of 22 K GH are removed from serum and non-22 K GH isoforms are quantitated. The 22 K GH exclusion assay (22 K GHEA) was established as a screening method to identify conditions in which the ratio of non-22 K GH isoforms to total GH in human blood is altered. A 22 K GH-speciflc monoclonal antibody (MCB) is used for binding to 22 K GH in serum. Magnetic beads coated with rat anti-mouse immunoglobulin G and a magnetic device are used to remove the 22 K GH-MCB complexes from serum. The non-22 K GH isoforms are measured by a polyclonal antibody-based immunoradiometric assay (GH-IRMA). The assay procedure was optimized systematically by statistical experimental designs. In serum spiked with monomeric or dimeric 22 K GH, the 22 K GH extraction was efficient at GH levels up to 100 μg/l (range 96.3–100%). The intra- and interassay precision for non-22 K GH levels of 3.9 μg/l were 2.6% and 8.7%, respectively, while for levels of 0.6 μg/l, which were very close to the detection limits of the assay, the coefficients were 17.0% and 21.6%, respectively. The percentage of non-22 K GH isoforms determined in serum samples from three different groups of subjects showed clearly distinctive values. The 22 K GHEA is a new method for evaluation of non-22 K GH isoforms in human blood under different physiological and pathophysiological conditions. Cesar L Boguszewski, RCEM, Sahlgrenska University Hospital, Bruna Stråket, 16 S-413 45 Göteborg, Sweden

Association of pituitary adenoma with neuronal christoma: A TEM study

1994 ◽  
Vol 52 ◽  
pp. 232-233
Author(s):  
Eva Horvath ◽  
Kalman Kovacs ◽  
B. W. Scheithauer ◽  
R. V. Lloyd ◽  
H. S. Smyth
Keyword(s):  
Growth Hormone ◽  
Pituitary Adenoma ◽  
Pituitary Tumor ◽  
Nervous Tissue ◽  
Alternative Explanation ◽  
Growth Hormone Releasing Hormone ◽  
Cell Hyperplasia ◽  
Releasing Hormone ◽  
Secretory Neurons

The association of a pituitary adenoma with nervous tissue consisting of neuron-like cells and neuropil is a rare abnormality. In the majority of cases, the pituitary tumor is a chromophobic adenoma, accompanied by acromegaly. Histology reveals widely variable proportions of endocrine and nervous tissue in alternating or intermingled patterns. The lesion is perceived as a composite one consisting of two histogenetically distinct parts. It has been suggested that the neuronal component, morphologically similar to secretory neurons of the hypothalamus, may initiate adenoma formation by releasing stimulatory substances. Immunoreactivity for growth hormone releasing hormone (GRH) in the neuronal component of some cases supported this view, whereas other findings such as consistent lack of growth hormone (GH) cell hyperplasia in the lesions called for alternative explanation.Fifteen tumors consisting of a pituitary adenoma and a neuronal component have been collected over a 20 yr. period. Acromegaly was present in 11 patients, was equivocal in one, and absent in 3.

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