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http://dx.doi.org/10.5713/ajas.2002.757

Characterization of Growth Hormone Secretion to Growth Hormone releasing Peptide-2 in Domestic Animals - A Review

Roh, Sang-Gun (Faculty of Agriculture, Shinshu University)
Lee, Hong-Gu (Dept of Animal Science and Technology, School of Agriculture and Life Science, Seoul National University)
Phung, Long Thang (Hue University of Agriculture and Forestry)
Hidari, Hisashi (Dept. of Animal Science, Obihiro University of Agriculture and Veterinary Medicine)

Publication Information

Asian-Australasian Journal of Animal Sciences / v.15, no.5, 2002 , pp. 757-766 More about this Journal

Abstract

Growth hormone-releasing peptide-2 (GHRP-2, also named KP102) is a new hexapeptide of a series of synthetic growth hormone-releasing peptides (GHRPs) which stimulates the secretion of growth hormone (GH) in vitro and in vivo in several species including calf, sheep and pig. The GH-releasing activity of GHRP-2 is two to three times more effective than that of the original GHRP-6, and GHRP-1 in the rats and humans. To date, GHRP-2 seems to be the most potent member of the family of GHRPs. Since the GHRPs are short peptides (5-7 amino acid residues), they are synthesized easily and are not as readily degraded in plasma as GHreleasing hormone (GHRH). These features ameliorate their potential on domestic animals because of their chemical nature the GHRPs are efficacious when administered i.v. orally or orally. However, studies in cow, pig and sheep do not indicate such a close relationship between GHRH, somatostatin (SS) and GH, calling into question the general applicability of the human and rat models. Perhaps there is an important role for an endogenous GHRP in the regulation of GH secretion in domestic animals. This review provides an overview on the current knowledge of physiological role of GHRP-2 in domestic animals.

Keywords

GHRP; GH; Calf; Pig; Sheep;

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