Growth hormone isoforms in a girl with gigantism.
J Pediatr Endocrinol Metab
; 12(1): 99-106, 1999.
Article
en En
| MEDLINE
| ID: mdl-10392356
Several previous investigations have suggested that there may be different growth hormone isoforms in patients with acromegaly. We used three different site-specific monoclonal antibodies (MAbs) to investigate growth hormone (GH) isoforms in serum from an 8 year-old girl with a GH and prolactin secreting adenoma. The pattern of GH-immunoreactivity was dependent on the circumstances of collection. Serum obtained after oral glucose had very little cross reactivity with MAb 352 although concentrations of up to 15 micrograms/l were found with two other MAbs, 033 and 665. MAb 352 does not recognize the 20,000 dalton isoform of GH (20K) while both MAb 033 and 665 do. The same pattern of GH immunoreactivity (low MAb 352, equal and higher MAb 033 and 665) was seen in other baseline samples. In contrast, samples obtained after TRH/GnRH showed immunoreactivity patterns expected for a mixture of 22,000 dalton isoform of GH (22K) with only a small amount of 20K. GH samples obtained during sleep showed both patterns with episodic peaks with equal immunoreactivity superimposed on the basal pattern (decreased activity with MAb 352). Affinity chromatography of basal samples showed that a portion of the GH immunoreactivity was neither 22K nor 20K, although in stimulated samples, over 70% of GH was 22K or 20K GH. In conclusion, the nature of GH isoforms present in serum varies with GH concentration. These differences may contribute to the known difficulty in correlating disease activity and random GH measurements in patients with GH secreting adenomas.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Hipofisarias
/
Hormona del Crecimiento
/
Prolactinoma
/
Gigantismo
Tipo de estudio:
Diagnostic_studies
/
Etiology_studies
Límite:
Child
/
Female
/
Humans
Idioma:
En
Revista:
J Pediatr Endocrinol Metab
Asunto de la revista:
ENDOCRINOLOGIA
/
PEDIATRIA
Año:
1999
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Alemania