The synthetic growth hormone release inhibiting hormone (GH RIH) was conjugated with human serum globulin using glutaraldehyde and administered to rabbits. An antiserum thus generated bound 70% of [125I]Try1 GH RIH. The binding was inhibited by unlabelled GH RIH and the inhibition was dose related, enabling one to establish a radioimmunoassay method for GH RIH. The minimum detectable dose was 4 pg. A linearity was demonstrated for immunoreactive GH RIH of extracts of rat and pig hypothalami, indicating that they contained substance(s) indistinguishable from GH RIH. Various hypothalamic and pituitary hormones did not interfere with the radioimmunoassay, but considerable cross reaction was observed from linear GH RIH and the ring portion of GH RIH, suggesting that the antigenic determinant involved the amino acid sequence from position 3-14 of GH RIH or part of it. Plasma protein appears to contain substance(s) immunologically indistinguishable from GH RIH or to interfere, in a nonspecific manner, with the radioimmunoassay system for GH RIH.
|Original language||English (US)|
|Number of pages||6|
|Journal||Proceedings of the Society for Experimental Biology and Medicine|
|State||Published - Mar 1975|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)