NON-SUPPRESSIBLE INSULIN-LIKE ACTIVITY IN LARON'S SYNDROME

1979 ◽  
Vol 90 (3) ◽  
pp. 414-420 ◽  
Author(s):  
Knud W. Kastrup ◽  
Jürgen Zapf
Keyword(s):  
Growth Hormone ◽  
Growth Factors ◽  
Growth Retardation ◽  
Binding Assay ◽  
Factor Activity ◽  
Protein Binding Assay ◽  
The Family ◽  
Low Activity ◽  
Severe Growth ◽  
Insulin Like Activity

ABSTRACT Severe growth retardation is found in patients with high levels of growth hormone and low sulphation factor activity or somatomedin. Also nonsuppressible insulin-like activity (NSILA-s) has been found to be very low in a patient with this condition as measured by bioassay, protein binding assay and radioimmunoassay and to be below activities found in hypopituitary patients. Partially purified NSILA-s restored the ability of serum to increase sulphation activity although full restitution may still depend on other factors. These findings support the hypothesis that NSILA-s belongs to the family of somatomedin and thus is involved in promoting growth, and that low activity of these growth factors is a primary cause of the growth retardation found in these patients.

THE INFLUENCE OF HYPOPHYSECTOMY ON NSILA CONCENTRATIONS IN THE DOG: EVIDENCE FOR PARTIALLY PITUITARY-INDEPENDENT REGULATION

1977 ◽  
Vol 86 (3) ◽  
pp. 498-503 ◽  
Author(s):  
J. E. Eigenmann ◽  
M. Becker ◽  
B. Kammermann ◽  
J. Zapf ◽  
W. Leemann ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Thyroid Hormone ◽  
Pituitary Gland ◽  
Normal Level ◽  
Binding Assay ◽  
Serum Samples ◽  
Protein Binding Assay ◽  
Before And After ◽  
Low Levels ◽  
Insulin Like Activity

ABSTRACT Non-suppressible insulin-like activity (NSILA) was determined in 5 dogs before and after hypophysectomy. All NSILA determinations were carried out on serum samples after acidic Sephadex G-50 chromatography by two different assay systems, i. e. a bioassay and a protein binding assay. The levels of NSILA decreased significantly after hypophysectomy and returned to near normal levels after 2 weeks. T3−, T4− and cortisol levels were drastically reduced during the entire period of the experiment. Several GH determinations after hypophysectomy revealed very low levels. Insulin-induced hypoglycaemia failed to provoke a rise of GH levels as late as 4 months after hypophysectomy. These findings indicate that: 1) The pituitary gland cannot be the site of synthesis of NSILA. 2) NSILA concentrations in the dog are maintained at a near normal level in the presence of very low growth hormone and thyroid hormone concentrations, so that these latter hormones do not appear to be the only regulatory factors concerned in NSILA synthesis.

Determination of Nonsuppressible Insulin-Like Activity in Human Serum by a Sensitive Protein-Binding Assay

1977 ◽  
Vol 23 (4) ◽  
pp. 677-682 ◽  
Author(s):  
Juergen Zapf ◽  
Ueli Kaufmann ◽  
Eugen J Eigenmann ◽  
E Rudolf Froesch
Keyword(s):  
Protein Binding ◽  
Human Serum ◽  
Binding Assay ◽  
Active Material ◽  
Weight Fraction ◽  
Biologically Active ◽  
Mean Values ◽  
Protein Binding Assay ◽  
Serum Fractions ◽  
Insulin Like Activity

Abstract We describe a sensitive protein-binding assay for non-suppressible insulin-like activity in human serum. It can detect as little as 0.2 microunits (corresponding to 0.5 ng) of the activity in 0.4 ml of the assay mixture. It is measured in a low-molecular-weight fraction (termed "biological material") obtained by chromatography of serum on Se¬phadex G-50 in 1 mol/liter acetic acid. This fraction has been shown earlier to contain nearly all this biologically active material that is present in serum. A partially purified carrier protein from human serum is used as the binding protein; different concentrations of a partially purified preparation of material with the activity serve as standards, which compete with 1251-labeled tracer for binding. Bio¬logical material dilutes more or less in parallel with the standard over a 10-fold concentration range. In the chro¬matographed serum fractions, displacing activity appears between 50 and 80% bed volume, with the peak at 60%, and coincides with the distribution and the peak of radio¬activity obtained by chromatography of tracer. A good correlation (γ = 0.88) is observed between the values determined for this activity in the rat fat-pad assay and the protein-binding assay, although the latter yields about twofold higher results (160 ± 37 milliunits/liter vs. 345 ± 65 milliunits/liter, mean values for 18 normal sera). Values determined in the protein-binding assay are decreased in hypopituitary patients (183 ± 27 milliunits/liter) and in¬creased in acromegalics (486 ± 88 milliunits/liter), in accord with the results of the bioassay (68 ± 21 milli-units/liter for hypopituitary patients, 293 ± 53 for acro¬megalics).

SEVERE GROWTH RETARDATION IN CHILDREN WITH INFLAMMATORY BOWEL DISEASE

PEDIATRICS ◽  
1970 ◽  
Vol 45 (3) ◽  
pp. 386-393
Author(s):  
Thomas D. McCaffery ◽  
Khosrow Nasr ◽  
A. M. Lawrence ◽  
Joseph B. Kirsner
Keyword(s):  
Inflammatory Bowel Disease ◽  
Growth Hormone ◽  
Corticosteroid Therapy ◽  
Growth Retardation ◽  
Bowel Disease ◽  
Gastrointestinal Symptoms ◽  
Hormone Response ◽  
The Third ◽  
Inflammatory Bowel ◽  
Severe Growth

From a group of 130 youngsters with inflammatory bowel disease, 22 were severely growth retarded (below the third percentile in height). This had preceded gastrointestinal symptoms for 1 to 11.4 years in 8 patients and corticosteroid therapy in 14. Endocrine evaluation demonstrated abnormally low 24-hour urinary gonadotropins in five of six patients more than age 16, and depressed growth hormone response to insulininduced hypoglycemia in 11 of 13 tested. Growth retardation in this group was attributed to a secondary hypopituitarism.

Growth retardation in Down syndrome in relation to insulin-like growth factors and growth hormone

2005 ◽  
Vol 37 (S7) ◽  
pp. 59-62 ◽  
Author(s):  
Göran Annerén ◽  
Karl-Henrik Gustavson ◽  
Vicki R. Sara ◽  
Torsten Tuvemo
Keyword(s):  
Growth Hormone ◽  
Down Syndrome ◽  
Growth Factors ◽  
Growth Retardation ◽  
Insulin Like Growth Factors
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