Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
|
| pubmed:dateCreated |
1977-10-28
|
| pubmed:abstractText |
The development of a radioimmunoassay for somatomedin-C has for the first time made it possible to discriminate between serum concentrations of a single peptide or closely related group of peptides and the net somatomedin activity measured by less specific bioassay and radioreceptor techniques. Antibodies to human somatomedin-C were raised in rabbits using a somatomedin-C ovalbumin complex as the antigen. A variety of peptide hormones at concentrations up to 1 muM are not recognized by the antibody. Insulin at concentrations >0.1 muM cross reacts in a non-parallel fashion; purified somatomedin-A is only 3% as active as somatomedin-C; and radiolabeled cloned rat liver multiplication stimulating activity does not bind to the antibody. Immunoreactive somatomedin-C can also be quantitated in the sera of a variety of subhuman species. Unusual assay kinetics, which are manifest when reactants are incubated under classic "equilibrium" assay conditions, appear to result from the failure of (125)I-somatomedin-C to readily equilibrate with the somatomedin-C serum binding protein complex. It is, therefore, necessary to use nonequilibrium assay conditions to quantitate somatomedin-C in serum. With this assay it is possible to detect somatomedin-C in normal subjects using as little as 0.25 mul of unextracted serum. Serum somatomedin-C concentrations in normal subjects were lowest in cord blood and rose rapidly during the first 4 yr of life to near adult levels. In 23 normal adult volunteers, the mean serum somatomedin-C concentration was 1.50+/-0.10 U/ml (SEM) when compared to a pooled adult serum standard. 19 children with hypopituitary dwarfism had concentrations below 0.20 U/ml. 17 of these were below 0.1 U/ml, the lower limit of sensitivity of the assay. The mean concentration in 14 adults with active acromegaly was 6.28+/-0.37 U/ml (SEM), five times greater than the normal volunteers. Significant increases in serum somatomedin-C concentrations were observed in 8 of 10 hypopituitary children within 72 h after the parenteral administration of human growth hormone. Three patients with Cushing's disease had elevated serum somatomedin-C concentrations (2.61+/-0.14 U/ml [SEM]). Three patients with hyperprolactinemia had normal concentrations (1.74+/-0.11 U/ml [SEM]).The important new discovery brought to light by quantitation of immunoassayable somatomedin in patient sera is that all previously used assays detect, in addition to somatomedin-C, serum substances that are not under as stringent growth hormone control.
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| pubmed:commentsCorrections |
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-1106154,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-1193005,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-1239190,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-13429201,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-13883680,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-14083170,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-173158,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-173163,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-237487,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-4339122,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-4364007,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-4370626,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-4371422,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-4550398,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-5316354,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-5482933,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-5565609,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-5922747,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-839329,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-853345,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-946140,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-947120,
http://linkedlifedata.com/resource/pubmed/commentcorrection/893668-967246
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
AIM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Sep
|
| pubmed:issn |
0021-9738
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
60
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
648-57
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| pubmed:dateRevised |
2009-11-18
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| pubmed:meshHeading |
pubmed-meshheading:893668-Acromegaly,
pubmed-meshheading:893668-Adult,
pubmed-meshheading:893668-Animals,
pubmed-meshheading:893668-Child, Preschool,
pubmed-meshheading:893668-Chromatography, Gel,
pubmed-meshheading:893668-Cushing Syndrome,
pubmed-meshheading:893668-Dwarfism, Pituitary,
pubmed-meshheading:893668-Fetal Blood,
pubmed-meshheading:893668-Humans,
pubmed-meshheading:893668-Immune Sera,
pubmed-meshheading:893668-Infant, Newborn,
pubmed-meshheading:893668-Male,
pubmed-meshheading:893668-Pituitary Diseases,
pubmed-meshheading:893668-Radioimmunoassay,
pubmed-meshheading:893668-Somatomedins
|
| pubmed:year |
1977
|
| pubmed:articleTitle |
Estimation of somatomedin-C levels in normals and patients with pituitary disease by radioimmunoassay.
|
| pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, U.S. Gov't, P.H.S.
|