The effects of growth hormone-releasing peptide-2 (GHRP-2) on the release of growth hormone and growth performance in swine.
The effects of GHRP-2 (also named KP102), a new growth hormone-releasing peptide, on the release of growth hormone (GH) and growth performance were examined in swine. The single intravenous (i. v.) injection of GHRP-2 at doses of 2, 10, 30 and 100 microg/kg body weight (BW) to cross-bred castrated male swine stimulated GH release in a dose-dependent manner, with a return to the baseline by 120 min. The peak GH concentrations and GH areas under the response curves (GH AUCs) for 180 min after the injections of GHRP-2 were higher (P < 0.05) than those after the injection of saline. The GH responses to repeated i.v. injections of GHRP-2 (30 microg/kg BW) at 2-h intervals for 6 h were decreased after each injection. The chronic subcutaneous (s.c.) administration of GHRP-2 (30 microg/kg BW) once daily for 30 days consistently stimulated GH release. The GH AUCs for 300 min after the injections on d 1, 10 and 30 of treatment in GHRP-2-treated swine were higher than those in saline-treated swine. However, chronic administration of GHRP-2 caused a partial attenuation of GH response between d 1 and 10 of treatment. The chronic s.c. administration of GHRP-2 also increased average daily gain for the entire treatment period by 22.35% (P < 0.05) and feed efficiency (feed/gain) by 20.64% (P < 0.01) over the saline control values, but did not significantly affect daily feed intake. These results indicate that GHRP-2 stimulates GH release and enhancing growth performance in swine.
Phung
L T
LT
Laboratory of Animal Production, Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, 2-11 Nishi, Inada-cho, Obihiro, Japan.
Inoue
H
H
Nou
V
V
Lee
H G
HG
Vega
R A
RA
Matsunaga
N
N
Hidaka
S
S
Kuwayama
H
H
Hidari
H
H
D000818:Animals; D019540:Area Under Curve; D001835:Body Weight; D004305:Dose-Response Relationship, Drug; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D013007:Growth Hormone-Releasing Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D006728:Hormones / Q000008:administration & dosage / Q000493:pharmacokinetics*; D007275:Injections, Intravenous / Q000662:veterinary; D007279:Injections, Subcutaneous / Q000662:veterinary; D016014:Linear Models; D008297:Male; D009842:Oligopeptides / Q000008:administration & dosage / Q000493:pharmacokinetics*; D011863:Radioimmunoassay / Q000662:veterinary; D011897:Random Allocation; D013552:Swine / Q000254:growth & development / Q000502:physiology*; D015430:Weight Gain
D006728:Hormones; D009842:Oligopeptides; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone; C091874:growth hormone-releasing peptide-2