Youdaev et al. (1) reported that (pyro)Glu-Ser-Gly-NH2 isolated from bovine hypothalami or made synthetically stimulates the release of growth hormone (GH). Therefore, we synthesized the tripeptide and tested it in several in vivo and in vitro assay systems for GH releasing activity. Our results demonstrate that (pyro)Glu-Ser-Gly-NH2 does not stimulate the release of immunoreactive GH from rat pituitaries in vitro in doses of 0.1-1000 nanog/ml. Similarly, (pyro)Glu-Ser-Gly-NH2, injected intravenously into rats in doses of 1μg and 10μg/rat or infused into a hypophysial portal vessel in doses of 0.01 μg and 0.1 μg/rat did not increase serum GH levels as measured by radioimmunoassay. When this tripeptide was injected intravenously in doses of 500 μg into sheep it did not raise plasma GH levels. These results demonstrate that under the conditions of this investigation (pyro)Glu-Ser-Gly-NH2 does not display any GH-releasing activity.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and biophysical research communications|
|State||Published - Dec 10 1973|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology