Stimulation of growth hormone release from rat primary pituitary cells by L-692,429, a novel non-peptidyl GH secretagogue.
Endocrinology
; 132(6): 2729-31, 1993 Jun.
Article
en En
| MEDLINE
| ID: mdl-8389289
ABSTRACT
L-692,429, a benzolactam derivative, stimulated GH release from rat primary pituitary cells in a dose-dependent manner. The concentration of L-692,429 required for half-maximal stimulation were 59.6 +/- 7.3 nM. Under the same conditions, GHRP-6 and GRF had EC50 values of 10.3 +/- 1.9 nM and 0.47 +/- 0.09 nM, respectively. L-692,428, the enantiomer of L-692,429, was inactive at a concentration as high as 2 microM. Like GHRP-6, L-692,429 had no effect on intracellular cAMP level; however, it synergized with GRF to further increase not only the accumulation of cAMP but also the release of GH. The magnitude of GH release stimulated by maximal concentrations of L-692,429 and GHRP-6 was comparable. Interestingly, when presented together in maximal concentrations, L-692,429 and GHRP-6 did not cause additional GH release when compared with either secretagogue alone. The L-692,429-stimulated GH release was completely inhibited by 20 nM somatostatin. To our knowledge, L-692,429 is the first non-peptidyl GH secretagogue which has a direct effect on the release of growth hormone from rat primary pituitary cells. Its effect is most likely mediated through a mechanism which is similar to that of GHRP-6.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Hipófisis
/
Tetrazoles
/
Benzazepinas
/
Hormona del Crecimiento
Límite:
Animals
Idioma:
En
Revista:
Endocrinology
Año:
1993
Tipo del documento:
Article