Growth without growth hormone: the "invisible" GH syndrome.
Growth hormone (GH) deficiency, diagnosed by radioimmunoassay (RIA) measurements of GH in blood after provocation or in continuous 24 h samples of venous blood, is usually associated with growth failure. 4 non-obese boys have been identified who had normal linear growth despite apparent GH deficiency by standard RIA. All 4 patients had normal GH concentrations as measured with an IM-9 cell radio-receptor assay (RRA). The RRA/RIA ratio of the 4 patients significantly exceeded that of controls. Thus, these patients secrete a molecule with normal GH receptor binding and bioactivity which is "invisible" to the standard GH RIA. This variant GH is possibly expressed from the human GH-V gene or a mutant allele.
D000172:Acromegaly / Q000097:blood; D000293:Adolescent; D001120:Arginine; D002648:Child; D006128:Growth / Q000187:drug effects; D013006:Growth Hormone / Q000097:blood / Q000172:deficiency* / Q000494:pharmacology; D006801:Humans; D007328:Insulin; D011863:Radioimmunoassay; D011869:Radioligand Assay / Q000379:methods; D011986:Receptors, Somatotropin / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D013577:Syndrome
D007328:Insulin; D011986:Receptors, Somatotropin; D011994:Recombinant Proteins; D013006:Growth Hormone; D001120:Arginine