These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Developmental changes in chicken and turkey insulin-like growth factor-I (IGF-I) studied with a homologous radioimmunoassay for chicken IGF-I.
    Author: McMurtry JP, Francis GL, Upton FZ, Rosselot G, Brocht DM.
    Journal: J Endocrinol; 1994 Aug; 142(2):225-34. PubMed ID: 7930995.
    Abstract:
    The development of a homologous radioimmunoassay (RIA) for chicken insulin-like growth factor-I (cIGF-I) and its use to investigate the developmental changes in IGF-I in the chicken and turkey is described. A double-antibody RIA has been developed using recombinantly derived cIGF-I as antigen, radiolabelled tracer and standard. The resulting immunoassay has a minimum detection limit of 0.035 ng and effective dose of 2.5 ng. Dose-response curves of chicken and turkey plasma and tissue extracts were parallel with cIGF-I standard. The antiserum is specific for IGF-I as no cross-reactivity with chicken IGF-II, insulin, glucagon, gastrin or avian pancreatic polypeptide was observed. We have also established that acid/ethanol extraction of chicken and turkey plasma reduced possible interference of IGF-binding proteins (IGFBPs) in the RIA. Comparison of IGF-I immunoactivity in unextracted and acid/ethanol-extracted samples following gel filtration under acidic and neutral conditions indicates that the cIGFBPs may be acid-labile. Analyses of samples from growing chickens and turkeys using the homologous avian reagents revealed higher IGF-I concentrations than if the IGF were quantified using heterologous mammalian-derived reagents. A similar pattern was observed when tissue extracts were assayed for IGF-I content. The application of the homologous RIA to monitor blood and tissue IGF-I levels during embryonic development and posthatch growth in avian species will provide more accurate comparisons of results from studies on the role of IGF-I in growth and metabolism of domestic birds.
    [Abstract] [Full Text] [Related] [New Search]