The effects of growth hormone-releasing peptide-2 (GHRP-2) on the release of growth hormone and growth performance in swine.
Phung. L T LT; 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
Key Findings
- IV GHRP‑2 (2‑100 µg/kg) triggers a rapid, dose‑dependent GH surge that returns to baseline by ~120 min.
- Repeated IV doses every 2 h cause diminishing GH responses, indicating short‑term desensitization.
- Daily sub‑Q GHRP‑2 (30 µg/kg) for 30 days maintains elevated GH AUCs and improves average daily gain by ~22% and feed‑gain efficiency by ~21% in swine.
Practical Outcomes
- For biohackers, this animal study supports the idea that GHRP‑2 can reliably boost GH when given at about 30 µg per kg body weight daily via sub‑cutaneous injection. It also hints that chronic use may lead to modest tolerance, so rotating doses or cycling could be useful. However, human results may differ, so start with low doses, monitor hormone levels, and watch for side‑effects.
Summary
In pigs, a single IV dose of GHRP‑2 caused a quick, dose‑dependent spike in growth hormone that fell back to normal after about two hours. Giving the peptide daily under the skin for a month kept hormone levels higher and made the animals grow faster and use feed more efficiently, without changing how much they ate.
Abstract
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.
Study Information
pubmed
2000
10.1016/s0739-7240(00)00050-3