Generation of polyclonal antiserum against the growth hormone secretagoguereceptor (GHS-R) - Evidence that the GHS-R exists in the hypothalamus, pituitary and stomach of rats
Yj. Shuto et al., Generation of polyclonal antiserum against the growth hormone secretagoguereceptor (GHS-R) - Evidence that the GHS-R exists in the hypothalamus, pituitary and stomach of rats, LIFE SCI, 68(9), 2001, pp. 991-996
Growth hormone (GH) secretagogues (GHSs), which stimulate GH secretion, are
synthetic compounds that act through the GHS receptor (GHS-R) which has be
en recently cloned. We raised an antiserum in a rabbit against a synthetic
peptide corresponding to amino acid residues 248-260 of the third intracell
ular loop of the rat GHS-R. A competitive immunoassay showed that the antis
erum had a specific affinity for the target peptide. To confirm the specifi
city of the antiserum, the GHS-R cDNA was stably expressed in COS-7 cells.
In Western blot analysis, the band was detected at 44 kDa in the extracts f
rom COS-7 cells expressing GHS-R (COS-7/tf3-2) but not in those from wild-t
ype COS-7 cells. Furthermore, while COS-7/tf3-2 cells were strongly immunos
tained for GHS-R, no GHS-R-like immunoreactivity was observed in wild-type
COS-7 cells. Immunoreactive bands were also observed at approximately 46 kD
a in the extracts from rat hypothalamus, pituitary and stomach by Western b
lot analysis. These studies are the first to show the existence of GHS-R pr
otein in the stomach. The antiserum for the GHS-R is sensitive and specific
, and it would be useful for clarifying the roles of GHS/ghrelin. (C) 2001
Elsevier Science Inc. All rights reserved.