title: Effect of growth hormone on the low level of growth hormone binding protein in idiopathic short stature.
abstract: OBJECTIVE
  Growth hormone receptor status was assessed in children with idiopathic short stature by evaluating plasma growth hormone-binding protein before and under GH therapy.
  
  
  METHODS
  Among 22 children presenting idiopathic short stature, 15 were randomly selected to be treated with GH (1.2 IU/kg/week); they were studied before and under GH therapy. Untreated patients served as a control group for age and GH effect.
  
  
  METHODS
  Twenty-two prepubertal children, aged 5-11 years, were studied. They presented growth retardation of -2.8 +/- 0.1 SDS (mean +/- SEM). All had normal GH secretion and their mean IGF-I plasma level was normal.
  
  
  METHODS
  Growth hormone-binding protein was measured using high pressure liquid chromatography gel filtration. The specific binding of 125I-hGH to the growth hormone-binding protein was expressed as a percentage of the total radioactivity.
  
  
  RESULTS
  Specific binding of 125I-hGH to the high affinity growth hormone-binding protein was low with a mean +/- SEM value of 11.1 +/- 0.9% of radioactivity. In the treated group, growth hormone-binding protein increased significantly after 3 months of treatment; it reached 21.1 +/- 1.0% of radioactivity (mean +/- SEM) in the eight children who have been treated for 18 months. In the seven untreated children, the growth hormone-binding protein value increased to 16.2 +/- 1.1% after 18 months; this value is significantly lower than that found in the GH-treated children, demonstrating that the GH effect is greater than the age-related increase in the growth hormone-binding protein. A positive correlation was found between IGF-I plasma levels and growth hormone-binding protein and also between growth velocity and growth hormone-binding protein.
  
  
  CONCLUSIONS
  The low growth hormone-binding protein and the response to high doses of GH suggest partial GH resistance at the receptor level, in this group of children with idiopathic short stature.
authors.affiliation: Unité 30, Institut National de la Santé et de la Recherche Médicale, Hôpital Necker-Enfants Malades, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Fontoura
authors.forename: E
authors.initials: E
authors.lastname: Mugnier
authors.forename: R
authors.initials: R
authors.lastname: Brauner
authors.forename: R
authors.initials: R
authors.lastname: Rappaport
authors.forename: M C
authors.initials: MC
authors.lastname: Postel-Vinay
mesh_terms: D002352:Carrier Proteins / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006128:Growth / Q000502:physiology; D006130:Growth Disorders / Q000097:blood* / Q000188:drug therapy; D013006:Growth Hormone / Q000627:therapeutic use*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D011986:Receptors, Somatotropin / Q000032:analysis / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D011986:Receptors, Somatotropin; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; C051815:somatotropin-binding protein